UA - Final

What urine contaminant could cause a falsely elevated level of urinary albumin, thus giving the false interpretation of kidney damage?

Blood from menstruation The level of protein and albumin in blood is far higher than that of urine. For this reason, women should be instructed not to collect urine samples for protein and albumin analysis during menstruation.

Which of the following characteristics of cerebrospinal fluid is present if blood is due to subarachnoid hemorrhage (SAH)?

Blood is evenly distributed in all tubes. If blood is due to SAH, then the main characteristic of the CSF collected is that blood is evenly distributed in all tubes. Also, the supernatant is pink when centrifuged within one hour and no clots will be visible upon standing. These characteristics help to differentiate between true hemorrhages and traumatic taps.

What is the fluid created in the abdominal cavity named?

Peritoneal fluid Peritoneal fluid is fluid created in the abdominal cavity. Amniotic fluid is the protective fluid found within the membranes that hold and surround an embryo or fetus. Cerebrospinal fluid is the fluid that surrounds and protects the spinal cord and brain. Pleural fluid is the fluid found in the cavity surrounding the lungs.

The fluid found in the cavity surrounding the lungs is called:

Pleural fluid Pleural fluid is the fluid found in the cavity surrounding the lungs. Peritoneal fluid is fluid created in the abdominal cavity. Amniotic fluid is the protective fluid found within the membranes that hold and surround an embryo or fetus. Cerebrospinal fluid is the fluid that surrounds and protects the spinal cord and brain.

Which of the following may be seen in a CSF sample of a patient that has a subarachnoid (intracranial) hemorrhage (SAH)?

Macrophages containing hemosiderin Characteristics of a subarachnoid hemorrhage (SAH) include even distribution of blood in tubes collected, no clot formation in the sample, as well as a xanthochromic supernatant to the sample. Another characteristic that correlates with a SAH is hemosiderin deposits in macrophages. As red blood cells degenerate, the breakdown products are seen in macrophages as dark, granular, iron-laden hemosiderin deposits.qe

Which of the following cells would be increased if the cerebrospinal fluid (CSF) of a patient suspected of having multiple sclerosis?

Lymphocytes Increased lymphocytes are typically associated with viral infections. There are also noninfectious causes for increased lymphocytes, such as multiple sclerosis. Infectious causes for increased lymphocytes include viral meningoencephalitis, aseptic meningitis syndrome, fungal meningitis, and syphilitic meningoencephalitis. Neutrophils in the CSF are indicative of a bacterial infection. Several infectious disorders result in an increase in neutrophils, such as untreated bacterial meningitis, viral meningoencephalitis, early tuberculosis, and mycotic meningitis. Macrophages can be seen in cases of meningitis or meningeal inflammation, infectious diseases, CNS leukemia, lymphoma, and malignant melanoma. Increased monocytes can be seen in tuberculous meningitis, syphilis, subarachnoid hemorrhage, and viral encephalitis.

The image on the right is a cytospin preparation of cerebrospinal fluid viewed at 1000X magnification. What is the identity of the primary blood cell type observed in this microscopic field?

Lymphocytes This is the normal range of variation for lymphocytes in a cytospin. There are no monocytes, macrophages, or mesothelial cells present in this image. Lymphocytes typically have condensed chromatin and scant blue cytoplasm. Small numbers are normal, but Increased numbers can be associated with viral infections, meningitis, and others. Monocytes are large cells, often with convoluted nuclei and large cytoplasms, and are infrequently seen in CSF. Sometimes they can be seen in meningitis or other conditions. Macrophages are not seen in normal CSF but can be seen in meningitis and other conditions. They are large cells with abundant cytoplasm. Mesothelial cells are not found in normal CSF. If present, the distinction from macrophages is sometimes difficult.

A patient suffering from typical leukemic symptoms presents in the emergency room. Physicians order a spinal tap after noticing possible central nervous system involvement. What are the cells seen in the spinal fluid cytospin preparation?

Lymphocytes and Blasts In this cerebrospinal fluid cytospin, the predominant cell type appears as large cells with irregularly shaped nuclei, prominent nucleoli, and scant cytoplasm. These cells are L2 Lymphoblasts and would be reported as blasts. Examples are indicated by the red arrows. There are also a few normal lymphocytes in this field as well. Examples are indicated by the blue arrows.

A technologist is having trouble differentiating between red blood cells, oil droplets, and yeast cells on a urine microscopy. Acetic acid should be added to the sediment to:

Lyse the red blood cells

What is the lower reference limit for semen volume according to the World Health Organization, WHO Laboratory Manual for the Examination and Processing of Human Semen, 5th edition?

1.5 mL The typical ejaculate contains usually between 2-5 mL of semen. According to WHO's reference limits, the lower reference limit for semen volume is 1.5 mL. Volumes above or below the reference intervals are associated with infertility.

A dilution commonly used for a routine sperm count is:

1:20 A manual sperm count is performed in the laboratory by using a Neubauer counting chamber. A dilution commonly used for the routine sperm count is a 1:20 dilution. The diluent is usually made of sodium bicarbonate and formalin which immobilize and preserve the sperm cells for the count.

What is the lower reference limit for progressive motility of spermatozoa when performing a semen analysis?

32% WTO grades sperm motility as progressive motility (PM), nonprogressive motility (NP), and immotility (IM). PM is defined as sperm moving linearly or in a large circle, NP is sperm moving without progression, and IM represents sperm with no movement. The lower reference limit for progressive motility is 32%. The lower reference limit for total motility (progressive + non-progressive) is 40 %.

Common crystals which can be found in ACID urine include:

Amorphous urates and calcium oxalate Amorphous urates and calcium oxalate are the only crystals from the choices listed that can be found in acid urine. Amorphous urates look like brick color or yellow/brown dust under the microscope, while calcium oxalate crystals are colorless and they can take the shape of envelopes, dumbbells, or ovals. Amorphous phosphates (white colorless, dust-like appearance) and calcium carbonate (colorless dumbbells appearance) are both found in alkaline urine.

How many white blood cells (WBCs) would be considered normal for adult cerebrospinal fluid?

0-5 WBCs/µL In an adult, 0 - 5 WBC/µL is considered normal. Children will have slightly higher cell counts. Up to 30 WBC/µL is within normal limits for newborns. Lymphocytes account for 60 - 100% of these cells.

The volume of urine recommended for centrifugation for a microscopic examination is:

10 - 15 mL It is good laboratory practice to centrifuge between 10 and 15 mL of urine (when available) to obtain an optimal sample for microscopic evaluation. The specimen is centrifuged and then the supernatant is discarded. The remaining 0.5-1.0 mL of sediment is used for the microscopic examination.

A 1:10 dilution is made on a CSF sample. Five squares on each side of the hemacytometer are counted for a total of 10 squares and a total of 150 cells are recorded. What is the count per microliter?

1500 According to the formula on the right, here is how we arrive a the 1500 cells per microliter:Cells/µL = 150 x 10/ 10 x 0.1 µL Cells/µL = 1500 / 1 = 1500/µL

All of the following urinalysis findings may correlate with the presence of a yeast infection, EXCEPT:

3+ red blood cells (RBCs) The presence of RBCs in the urine is associated with damage to the glomerular membrane or vascular injury within the genitourinary tract. A urine specimen containing glucose provides an ideal medium for the growth of yeast. A true yeast infection should be accompanied by the presence of WBCs since the combination of the yeast and cellular elements drawn to the area of infection will cause turbidity to appear in the urine.

For BEST results, if not tested immediately, a semen sample should remain at which of the following temperatures following collection?

37 ºC Preferably, a semen sample should remain at 37° C following collection, which helps to maintain sperm integrity. The specimen should be tested within 1 hour of collection.

Which of the following would be considered a normal value for a glucose level in cerebrospinal fluid?

60 mg/dL CSF glucose levels should be approximately 60 to 70% of plasma levels. In our answer choices, 60mg/dL is the best option, as the serum glucose values will be just between 90-100 mg/dL. For a CSF glucose to be 30mg/dL, the serum value would be around 45mg/dL which is abnormally low. For the other two answer choices, the CSF values are already above the normal serum values, therefore are not considered normal values.

A technologist performed a STAT spinal fluid count by pipetting undiluted spinal fluid in a Neubauer Counting Chamber and counting both sides of the chamber (4 large WBC squares on each side). A total of 54 White Cells were counted. How many White Cells would there be per cubic millimeter?

67.5 First, determine the number of WBC's from the hemacytometer as follows: WBC/µL= Avg # cells counted /(# squares counted x 0.1 µL) WBC = 54 / (8 squares x 0.1 µL) = 67.5/µL Since 1 µL = 1 cubic millimeter, then the answer is 67.5/µL. *Note in this question, both sides were counted without separate values given for the average to be obtained; therefore, substitute the total cell count in the numerator with the total squares counted in the denominator. Also, there was no dilution for the specimen, so the dilution factor will not be included in the equation.

What is the approximate volume of spinal fluid in an adult?

90-150 mL The approximate volume of CSF in an adult is 90-150 mL and about 10-60 mL in neonates. The CSF is produced in the choroid plexuses of the lumbar ventricles and the third and fourth ventricles. Adults produce about 20 mL of CSF per hour. The fluid is reabsorbed at the same rate it is produced by the arachnoid granulations/villae back into the blood capillaries.

A CSF glucose value is 62 mg/dL. What would you estimate the serum glucose?

93 mg/dL CSF glucose is roughly estimated to be about 2/3 of the serum glucose level in mg/dL. Therefore: 62 mg/dL = 2/3 x serum glucose serum glucose = 62 mg/dL x 3/2 serum glucose = 93 mg/dL

Oliguria is usually correlated with:

Acute glomerulonephritis Acute glomerulonephritis is closely associated with oliguria (decreased urine output), and occasionally anuria (no urine output).

Below is a urinalysis report on a 37-year-old woman seen in the ER with headache, hypertension, weight loss, and mild edema: Color: red Clarity: cloudy Sp. Gravity 1.010 pH 5.0 Glucose: negative Protein: 3+ Ketones: negative Nitrite: negative Blood: moderate Urobilinogen: normal Microscopic: 25-50 RBC2-4 WBC2-5 granular casts2-5 hyaline casts0-2 RBC castsfew epithelial cells Based on the urinalysis report above, the MOST probable diagnosis of this patient's condition is:

Acute glomerulonephritis Both the clinical symptoms and laboratory findings point to acute glomerulonephritis. Acute glomerulonephritis is active inflammation in the glomeruli. In the chemical and microscopic urinalysis, signs of acute glomerulonephritis include red blood cells, white blood cells, proteinuria, and casts. The casts are commonly cellular and are composed of cells that have leaked through the glomeruli where they develop into cylindrical forms inside of the tubule

The reagent strip method for protein primarily tests for which type of protein?

Albumin Increased level of protein in the urine (proteinuria) is an indicator of renal disease. The glomerular membrane prevents the passage of high molecular weight proteins including albumin (mol wt 69,000). The reagent test strip reaction is based on the "protein error of indicators" principle which means that the point of the color change of pH indicators is different when protein is present versus when protein is not present. This phenomenon occurs because proteins act as hydrogen ion acceptors at a constant pH. Albumin is the main protein that is measured by the urine protein pad on the reagent strip because it contains more amino groups to accept hydrogen ions than other groups. Albumin is also the protein that is found in the highest concentrations in the body.

A 51-year-old woman with Type 2 Diabetes and high blood pressure has recently started noticing foaming in the toilet bowl following urination. She typically has her urine checked for abnormalities every 3 months. Recently, urinalysis indicates an abnormally large concentration of protein in her urine. Given the patient's history, which of the following proteins will likely be found in the urine upon analysis in the laboratory?

Albumin, which leaks through damaged kidney glomeruli and appears first in the urine The correct answer is: albumin, which leaks through damaged kidney glomeruli, and appears first in the urine. In healthy people, the kidney glomeruli act as filters to keep albumin and other necessary proteins in your body, while filtering out excess water, urea, and other waste. Damaged kidney glomeruli, often resulting from Diabetes, allow necessary proteins to pass into the urine - albumin being one of the first to pass through, owing to its high concentration and relatively small molecular size. Beta amyloids are indicated in Alzheimer's disease and there is very interesting current research relating elevated beta-amyloid levels to lack of sleep. Gamma globulins are just a type of immunoglobulin and they have no relation to diabetes and kidney disease. The "M-spike" refers to a sharply increased quantity of a single type of immunoglobulin, produced by a single type of plasma cell in multiple myeloma. This "spike" is detected by electrophoresis, which is not part of a routine urinalysis.

Which of the following tests is the BEST screening test for neural tube defects?

Alpha-fetoprotein Alpha-fetoprotein is produced by the fetal liver. It is measured in pregnant women, using maternal blood or amniotic fluid, as a screening test for a subset developmental abnormalities. Abnormally high levels of this substance is associated with defects in the fetal neural tube, while abnormally low levels are associated with the presence of Down' syndrome.

What is the identification of this crystal seen in a urine specimen with an alkaline pH?

Ammonium biurate Ammonium biurate crystals commonly occur in the form of "thorn apples," as shown here, or in polyhedral shapes. They are deeply colored from a dark-yellow to brown. Uric acid crystals are variably shaped: they occur as flat diamond (four-sized), rhombic, lemon-shaped, or rarely hexagonal shapes with a yellowish or yellowish-brown coloration. They are present in acid urine. They are polarizable and show various colors when polarized. They may be present in normal urine. Triple phosphate crystals appear as colorless prisms with 3 to 6 sides and oblique ends, or as "feathery sleeves". They have been described as "coffin lid shaped", and can occur normally in alkaline urine. They may indicate the presence of an infection. Calcium carbonate crystals are colorless with a dumbbell or spherical appearance and are found in alkaline urine.

The protective fluid found within the membranes that hold and surround an embryo or fetus is called:

Amniotic fluid The protective fluid found within the membranes that hold and surround an embryo or fetus is called amniotic fluid. Peritoneal fluid is fluid created in the abdominal cavity. Cerebrospinal fluid is the fluid that surrounds and protects the spinal cord and brain. Pleural fluid is the fluid found in the cavity surrounding the lungs.

Substances found in urinary sediment that are more easily distinguished by the use of a polarized microscope are:

Anisotropic cholesterol droplets Anisotropic cholesterol droplets tend to form a "maltese cross" pattern when viewed in polarized light, which helps to differentiate them from other urine microscopic components.

What are the microscopic elements that are indicated by arrows in this image?

Bacteria

The image on the right is a Wright-Giemsa stained CSF smear (1000X). What structures are indicated by the arrows?

Bacteria The arrows are pointing to bacteria. This is a CSF slide from a patient diagnosed with bacterial meningitis. Platelets would appear with granular edges. Generally, platelets are not found in spinal fluid, unless there is a traumatic tap. Stain precipitate would be inconsistent in size. Malarial parasites are primarily found intracellularly (inside RBCs).

A cloudy CSF sample has a white count of over 1,000 WBC/µL. The large number of these cells seen in the cytocentrifuged smear in this illustration is suggestive of:

Bacterial Infection Almost exclusively segmented neutrophils are seen, suggestive of bacterial infection. In general, CSF white cell count would be in the thousands per µL in bacterial meningitis. In fungal infections, yeast form may be seen in CSF. Fungal meningitis occurs primarily in patients who are immunocompromised. With immune cells (including macrophage) being dysfunctional, CSF white count would not be as elevated, although the usual cellular response against fungal infection is the interaction between the antigen-presenting cell and the effector T lymphocytes. In cryptococcal meningitis, for example, CSF white count may be only mildly elevated particularly in patients undergoing "immune reconstruction inflammatory syndrome." Lymphocytes are elevated in viral meningitis. In general, CSF white cell count would be in the hundreds per µL. Malaria parasites infect red cells in circulation, not in CSF.

Bacterial contamination of a urine specimen from a normal healthy individual could originate from all of the following except:

Bladder Urine in the bladder is normally sterile unless an infection is present. Normal genital flora can be introduced in the collection container if the specimen is not collected appropriately (clean-catch, suprapubic aspiration, or catheterization). Most Urinary Tract Infections (UTIs) start in the lower urinary tract due to fecal contamination.

Identify the important blood cells displayed in this cerebrospinal fluid sample.

Blast cells The correct answer here is blasts. Many of the cells in this image are blasts; lymphoblasts to be exact. This smear should be sent for review and the clinician should be notified. The presence of blasts of any type in the cerebrospinal fluid is always abnormal. Atypical lymphocytes would also display nucleoli but would have extended cytoplasmic walls that are typically indented from surrounding RBCs. Basophils are typically present within the blood during an allergic event. Basophils are also the least common of all granulocytes. Their large granules stain a dark blue-purple color. Monocytes are typically three to four times the size of RBCs with an irregular cytoplasm shape. Monocytes can contain vacuoles. No nucleoli appear within the cytoplasm as seen in blasts and atypical lymphocytes.

What types of cells are NOT present in this field of a cytocentrifuged CSF sample?

Blasts There are no blasts seen in this image. The lymphocytes seen here are mature, though from cytocentrifugation they can appear to have prominent nucleoli similar to blasts. The chromatin pattern of the nucleus in the lymphocytes shown is mature and clumped. Neutrophils and RBCs are also easily observed in the image.

A patient reported to her doctor that her stools have been ribbon-like over the last few weeks. What is most likely the cause of the patient's stool appearance?

Bowel obstruction The most likely cause of ribbon-like stools is bowel obstruction, where the normal passage of fecal waste is restricted in some way. Diarrhea would result in a watery stool. If the patient was constipated, you would expect the stool to be small and hard. Inflammation of the intestinal wall would result in mucus-coated stools.

After suspecting that his patient may have lung disease, the physician sends a bronchoalveolar lavage (BAL) to the laboratory for examination. What is the cell type noted by the arrows in this cytospin sample?

Bronchial lining cells The cells shown in this bronchoalveolar lavage (BAL) are bronchial lining cells. The cells have a rounded nucleus at one end of the cell with a column of cytoplasm. A few have intact cilia while others do not. The presence of cilia definitively identifies this cell type. The presence of these cells indicates that the specimen was obtained from the upper respiratory tract as opposed to deeper within the lung. Lymphocytes have a rounded nucleus. The cytoplasm typically surrounds the nucleus. They may be present in BAL specimens. Mesothelial cells are not seen in BAL specimens. They are lining cells that may be found in other serous body fluids Macrophages have differentiated from monocytes and can be found in BAL and other body fluids. They are large and have a round or oval nucleus. They are phagocytic cells, so the cytoplasm is often filled with debris and/or vacuoles.

Homogentisic acid in urine will cause urine to be which of the following colors?

Brown/black The presence of homogentisic acid in urine will cause urine to be brown/black. Homogentisic acid in the urine is found in Alkaptonuria, an inherited amino acid disorder. These individuals lack an enzyme that breaks down homogentisic acid. Green-colored urine can be associated with Pseudomonas infections. Pink urine is most commonly associated with the presence of a small amount of blood. Port-wine-colored urine is associated with porphyrins

What is the identification of these crystals seen in a urine with an acid pH?

Calcium oxalate The crystals in the image below are composed of calcium oxalate. Calcium oxalate crystals have a refractile square envelope shape and can be seen in acid or neutral urine. They characteristically occur as octahedral or envelope shapes. Calcium oxalate crystals can also be viewed as having a Maltese cross when one focuses up and down through the crystal. Uric acid crystals are variably shaped: they occur as flat diamond (four-sized), rhombic, lemon-shaped, or rarely hexagonal shapes with a yellowish or yellowish-brown coloration. They are present in acid urine. They are polarizable and show various colors when polarized. They may be present in normal urine. Triple phosphate crystals appear as colorless prisms with 3 to 6 sides and oblique ends, or as "feathery sleeves". They have been described as "coffin lid shaped", and can occur normally in alkaline urine. They may indicate the presence of an infection. Calcium carbonate crystals are colorless with a dumbbell or spherical appearance and are found in alkaline urine.

Which of the following would be the most characteristic finding in synovial fluid in a case of pseudogout?

Calcium pyrophosphate crystals Calcium pyrophosphate crystals are characteristic of pseudogout. Pseudogout is a result of endocrine disorders that produce high levels of calcium in serum. It can also be a result of degenerative arthritis producing cartilage calcification. Monosodium urate crystals are the causative agent for gout. Macrophages can be normal in synovial fluid, but large quantities may be associated with viral infections. RBCs are not usually seen and WBCs are usually seen in viral or bacterial infections. None of then cause pseudogout.

Which of the following are characteristics of normal CSF?

Clear Normal CSF is clear and colorless. The presence of increased WBCs, microorganisms, and protein can cause CSF to appear turbid. Xanthochromic fluid will be pink, orange, or yellow due to the presence of RBC degradation. Disorders affecting the blood-brain barrier and fluid collected from a traumatic tap may form clots from past introduction of plasma fibrinogen into the specimen.

The renal threshold is best described as:

Concentration at which a substance in the blood spills into the urine The renal threshold is the maximum amount of a substance that the kidney can prevent from entering into the urine. Such an example is glucose in urine. The renal threshold for urine is about 160 to 180 mg/dL of glucose. Once this limit is surpassed, glucose will no longer be reabsorbed by the kidney and it will appear in the urine.

The Clinitest® reaction is based on which of the following principles?

Copper reduction Clinitest® is a reagent tablet that is based on the classic Benedict's copper reduction reaction. It is performed on pediatric specimens in order to check for the presence of reducing substances. This additional step is an easy way of screening for inborn metabolic problems, in particular, galactosemia.

The measurement of sodium and chloride in the sweat is the most useful test for the diagnosis of what condition/disease?

Cystic fibrosis Measurement of the sodium and chloride concentration in sweat is the most useful test in the diagnosis of cystic fibrosis. Significantly elevated concentrations of both ions occur in more than 99% of affected patients.The definitive test for steatorrhea (failure to digest or absorb fats) is the quantitative fecal fat analysis.The secretin/CCK (cholecystokinin) test is the direct determination of the exocrine secretory capacity of the pancreas.Pancreatic cell tumors, which overproduce gastrin, are called gastrinomas; they cause Zollinger-Ellison syndrome and can be duodenal in origin.

Identify the urine sediment elements shown by the arrow:

Cystine crystals Cystine crystals are characteristically seen as colorless hexagonal plates in acid urine. They may be confused with hexagonal uric acid crystals. They can be differentiated from uric acid by their solubility in dilute hydrochloric acid versus crystalline uric acid, which is not soluble in dilute hydrochloric acid. The cyanide-nitroprusside test can be used to confirm the presence of cystine in the urine. Cystine crystals are not present in normal urine. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners. They are soluble in hot alcohol and ether. Uric acid crystals are variably shaped: they occur as flat diamond (four-sized), rhombic, lemon-shaped, or rarely hexagonal shapes with a yellowish or yellowish-brown coloration. They are present in acid urine. They are polarizable and show various colors when polarized. They may be present in normal urine. Amorphous urates are found in acid urine and look like brick color or yellow/brown dust.

The crystals seen in these images are:

Cystine crystals There are cystine crystals depicted in these images. Cystine crystals are present in acidic urine, are typically colorless, and have a characteristic hexagonal shape. These crystals are associated with cystinuria. Leucine crystals are associated with liver disease and are found in acid to neutral pH urine specimens. One will notice the yellow color, concentric circles, and radial striations as characteristics of leucine crystals. Bilirubin crystals are yellow, needle-like crystals that may appear in clumps. They are found in acid urine and are associated with liver disease. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners. They are associated with nephrotic syndrome.

The nitrite portion of the test strip can be used to do all of the following EXCEPT:

Detect metabolic by-products often seen in diabetic patients The nitrite portion of the test strip can be used to monitor antibiotic therapy, detect a bladder infection in an early stage in pregnant women, screen individuals with recurrent infections, and other conditions such as the presence of cystitis. The test reaction on the urine chemical reagent strip pad for nitrite works by detecting when nitrite in the urine reacts with para-arsanilic acid to form a diazonium compound. This diazonium compound in turn couples with 1,2,3,4-tetrahydrobenzo(h)quinoline-3-ol to produce a pink color.The ketone portion of the reagent strip can be used to determine the presence of acetoacetate, a by-product of fat and/or protein metabolism. The presence of ketones in the urine is often associated with diabetes.

Which of the following conditions is associated with a positive ketone test on the urine test strip?

Diabetes mellitus Findings of ketones on the urine test strip are associated with diabetes mellitus. A positive blood urine test strip reaction can be caused by renal calculi. Bilirubin in urine is associated with hepatitis/cirrhosis. A positive nitrite pad would be indicative of urinary tract infection.

The image shown is a cytospin preparation of cerebrospinal fluid (CSF). What is the blood cell type that is indicated by the arrow?

Eosinophil The cell that is indicated by the arrow is an eosinophil. Eosinophils typically have a bilobed nucleus and cytoplasm filled with many large granules, which appear bright orange-red in color with Wright stain. Segmented neutrophils have small purple granules in the cytoplasm, and the nuclei have more lobes. Monocytes are large mononuclear cells. A macrophage is a phagocytic cell, similar to a monocyte, that may show ingested material in the cytoplasm.

Charcot-Leyden crystals in stool may be associated with an immune response and are thought to be the breakdown products of:

Eosinophils Charcot-Leyden crystals in stool are thought to be created from damaged eosinophil byproducts. These crystals have a strong association, although they are rare, with parasitic infections or allergic reactions.

When an automated or semi-automated method is used to read urine reagent strips, quality control testing must be performed at least:

Every day of patient testing and when a new bottle is opened. Reagent strips must be checked every 24 hours with both a positive and negative control. QC must also be performed when a new bottle of reagent strips is opened, when the results that are obtained are questionable, or when the integrity of the reagent strips is in question. Performing QC once a week or once a month is not acceptable. Performing QC for each new operator on the urinalysis bench is not necessary.

Identify the urine sediment element: CAST

Fatty cast Fatty casts contain refractile oval fat bodies or free fat droplets. They are derived from renal tubular cells and may be seen in nephrotic syndrome. Confirmation of fatty casts is done with the help of polarized microscopy (cholesterol forms Maltese crosses) and Sudan III and Oil Red O fat stains (neutral fats and triglycerides stain orange).

Which test uses a vaginal fluid specimen to differentiate amniotic fluid from urine and other body fluids?

Fern test The fern test is the correct answer. It is used to evaluate the presence of amniotic fluid in cases of premature membrane rupture. Vaginal fluid is observed microscopically on a slide for "fern-like" crystals, formed by protein and sodium chloride content. Spectrophotometric analysis of amniotic fluid measures the change in optical density (OD) of bilirubin. The absorbance difference at 450 nm is plotted on a Liley graph to determine the severity of fetal distress in hemolytic disease of the newborn (HDN). Osmolality measures particles in solution, such as sodium and chloride, and is used for the evaluation of renal concentrating ability. The amine (Whiff) test uses KOH and saline vaginal fluid suspension to detect the presence of a "fishy" odor due to the volatilization of amines produced by anaerobic bacteria in bacterial vaginosis (BV).

Which of the following artifacts may be mistaken for casts?

Fibers Fibers can be mistaken for casts on occasion, especially hyaline casts. Fibers, however, are usually thinner and appear less uniform in structure than casts do. As a result, they can contaminate a urine specimen from clothing and diapers and be confused with casts by inexperienced techs. To differentiate fiber artifacts from most casts, the specimen can be examined by the tech under polarized light. This is because fibers polarize while most casts do not.

Conditions that produce elevated CSF protein levels include all of the following EXCEPT:

Fluid leak Fluid leak would result in a decreased protein level. Any condition that causes damage to the blood-brain barrier mostly likely will cause elevated protein levels in the CSF. Meningitis, multiple sclerosis, and hemorrhage would all result in elevated protein levels in the CSF.

All of the following tests are part of the routine semen analysis, EXCEPT:

Fructose level Routine semen analysis includes appearance, volume, viscosity, pH, sperm count and concentration, motility, and morphology. The Fructose test is not employed for routine seminal fluid analysis, but may be performed as a special functional test if there is a low sperm count. The seminal vesicles are the source of fructose in semen and fructose is used by the spermatozoa as an energy source.

All of the following hormones are produced primarily in the pancreatic islets EXCEPT which one?

Gastrin

Which of the following conditions will cause a positive reagent strip blood result due to hematuria?

Glomerulonephritis Hematuria may be caused by glomerulonephritis, renal calculi, and pyelonephritis. Hemoglobinuria, on the other hand, can be caused by hemolytic anemia and severe burns. Dehydration will not cause hematuria.

All of the following parameters are generally considered to be a part of seminal fluid analysis, EXCEPT?

Glucose concentration Glucose concentrations are not performed during semen analysis procedures. However, sperm count, morphologic examinations, viscosity assessments, motility, appearance, volume, and pH, assessments are usually included in a semen analysis procedure.

An increased number of the cells seen in the image, upon microscopic examination of urine is termed:

Hematuria Hematuria indicates the presence of red blood cells in the urine. Glycosurea indicates glucose in the urine. Uremia indicates an increase of urea nitrogen in the blood.

A reagent strip test for hemoglobin has been reported positive. Microscopic examination fails to yield red blood cells. This patient's urine condition can be called:

Hemoglobinuria Hemoglobinuria, or the presence of hemoglobin in the urine, indicates that red cells have lysed and released their intracellular hemoglobin. Because the cells are no longer intact, you will not see red cells during microscopic examination. Remember that the urine strip detects hemoglobin itself, not only intact red blood cells. Hematuria is the presence of blood in urine, both microscopically and detected by the urine strip. Oliguria is a decrease of urine output, less than 400 mL/day in adults. Hemosidenuria is the presence of denatured ferritin (called hemosiderin) in the urine sediment.

A spectrophotometric scan of amniotic fluid may be valuable in the determination of which of the following conditions :)

Hemolytic disease of the newborn Amniotic fluid bilirubin is elevated in hemolytic disease of the newborn. It is determined by using the absorbance spectrum of amniotic fluid to determine the increase in absorbance at 450nm, which is the absorbance peak for bilirubin. This value, along with the gestational age, are used in Liley's three zone chart to determine the risk of severe fetal hemolysis.

A spectrophotometric scan of amniotic fluid may be valuable in the determination of which of the following conditions:

Hemolytic disease of the newborn Amniotic fluid bilirubin is elevated in hemolytic disease of the newborn. It is determined by using the absorbance spectrum of amniotic fluid to determine the increase in absorbance at 450nm, which is the absorbance peak for bilirubin. This value, along with the gestational age, are used in Liley's three zone chart to determine the risk of severe fetal hemolysis.

A technologist performed urine microscopic testing on a patient who submitted a urine sample following strenuous exercising. Which of the following casts is most likely to be found in this urine sample?

Hyaline casts The presence of 0-2 hyaline casts per low power field is considered normal, and it can be found following strenuous exercising, dehydration, heat exposure, and emotional stress. White cell casts are seen in renal infection or inflammation such as pyelonephritis. Granular casts are composed of plasma protein aggregates and cellular remnants. Waxy casts are refractile with squared-off ends and are associated with chronic renal failure.

The viscosity of the synovial fluid is due to synoviocyte secretion of mucopolysaccharide, which contains:

Hyaluronic acid Normal viscosity of synovial fluid comes from the polymerization of hyaluronic acid, which provides proper joint lubrication. Acid phosphatase is an enzyme component of semen produced by the prostate gland. The acidic, enzymatic fluid produced by the prostate gland functions in the coagulation and liquefaction of semen. Phosphatidyl glycerol and lecithin are lung surfactants present in amniotic fluid that serve as indicators of fetal lung maturity.

The primary mechanism responsible for glomerular filtration is:

Hydrostatic differential in glomerular tufts The hydrostatic pressure in the capillaries of the glomerular tuft drives the filtrate across their semipermeable membrane. The normal glomerular filtrate is similar in composition to the plasma, with the exception that molecules with a molecular weight of greater than about 70,000 daltons are not filtered.

A low CSF glucose level is associated with all the following EXCEPT:

Hyperglycemia In hyperglycemia, you would expect a normal or elevated CSF glucose level. A decreased (low) CSF glucose level, can be found in cases of acute bacterial, fungal, amebic, and trichinosis meningitis, as all these organisms consume the glucose in CSF.

Which of the following tests confirms the presence of Bence-Jones proteinuria:

Immunoelectrophoresis Immunoelectrophoresis is used to detect the presence of Bence-Jones proteins. Immunoelectrophoresis is used to help detect, diagnose, and monitor the course and treatment of conditions associated with abnormal proteins (such as Bence-Jones), including Multiple Myeloma, Waldenstrom's macroglobulinemia, and a few other related diseases.

Lymphocyte pleocytosis refers to a(n) _____________ in a CSF when compared to a normal sample.

Increased number of lymphocytes The presence of a greater than normal number of lymphocytes in the spinal fluid is termed lymphocyte pleocytosis. Typically, the majority of cells seen in a normal adult CSF specimen are lymphocytes and monocytes (70:30 ratio). This ratio is reversed in children.

Which of the following methods would be employed to collect sweat for chloride analysis:

Iontophoresis Iontophoresis is the gold standard for the collection of sweat for sweat chloride analysis. Pilocarpine iontophoresis actually stimulates the production of sweat, which is absorbed within a gauze pad which was previously weighed dry. The sweat sample is weighed to determine how much sweat was collected. Finally, the sweat sample is analyzed for its concentration of chloride. This particular test is utilized very commonly for the screening of cystic fibrosis since these patients typically exhibit higher levels of sweat chloride. In children over the age of 6 months to adults, the reference ranges are: Equal to or less than 39 mmol/L = Cystic Fibrosis is not likely to be present (rules-out CF) 40 - 59 mmol/L = Intermediate Level (Cystic Fibrosis may be present, further testing required) Greater than or equal to 60 mmol/L = Cystic Fibrosis is most likely present

Which one of the following statements about urea is false?

It is decreased in dehydration Urea is actually increased, not decreased, during bouts of dehydration. Urea accounts for 75% of nonprotein nitrogen excreted by an individual, it is elevated in a variety of glomerular, tubular, interstitial, and vascular renal diseases, and the serum reference range for normal individuals is 6 to 20 mg/dL when expressed as blood urea nitrogen.

Name structure A from the image below: Urinary System

Kindeys

Which of the following tests on amniotic fluid would be included when assessing fetal lung maturity:

L/S Ratio The correct answer choice here is L/S ratio. The lecithin/sphingomyelin ratio is determined by examining the amniotic fluid of a pregnant mother. Because amniotic fluid is continuously swallowed or inhaled and then replaced or exhaled in uterus the ratio can be measured to determine how much surfactant is in the fetal lungs. This ratio will help determine how well the infant's lungs will perform breathing at birth. Alpha-fetoprotein is used in assessing the potential for genetic disorders. Bilirubin is used in diagnosing the cause of jaundice and other liver problems.Fetal hemoglobin is not used to assess fetal lung maturity.

Which of the following sites is used most often for CSF collection?

L3-L4 CSF is routinely collected by lumbar puncture between the third, fourth, or fifth lumbar vertebra. CSF is produced in the choroid plexuses of the two lumbar ventricles and the third and fourth ventricles. The Subarachnoid is the space where CSF flows and its located between the arachnoid and pia mater.

In a normal CSF the protein concentration as compared to that in the plasma is generally:

Less than 1% The proteins found usually in plasma are the same ones as the ones found in CSF, except that in CSF the protein levels are much much lower. Normal ratio of plasma to CSF protein is about 200 to 1, or less than 1%. Elevation of CSF total protein is a nonspecific finding, but usually indicates some type of disease involving the brain or meninges. Contamination of CSF with blood due to events such as traumatic tap can elevate the CSF protein levels.

All of the following crystals are found in normal urine, EXCEPT?

Leucine Calcium oxalates can be found in normal urine at varying pH levels. Ammonium biurate and triple phosphate can be found in normal alkaline urine. Leucine crystals are always abnormal and can be found in maple syrup urine disease.

Identify the urine sediment elements shown by the arrow: :(

Leucine crystals Leucine crystals appear as oily, highly refractile, yellow to brown spheroids with radial concentric laminations. They are found in acid urine in patients with maple syrup urine disease. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners. They are soluble in hot alcohol and ether. Uric acid crystals appear in acid urine and resemble yellow-brown four-sided flat planes, rosettes, or wedges. Cystine crystals are present in acidic urine, are typically colorless, and have a characteristic hexagonal shape (also described as appearing similar to a benzene ring). These crystals are associated with cystinuria.

Which of the following is characteristic of an exudate effusion?

Leukocyte count greater than 1,000 WBC/µL

A patient presents to his family doctor with respiratory issues. He has a history of being a heavy smoker for more than 20 years, so the physician orders a BAL cell count with differential. Which of the following cells would most closely correlate with the patient's medical history?

Macrophages with purple/black inclusions Macrophages containing purple/black inclusions would most closely correlate with the patient's medical history of being a heavy smoker for more than 20 years. These cells contain hemosiderin and are also known as siderophages. Macrophages with phagocytized red blood cells would correlate with the normal removal of old red blood cells from circulation by the macrophages in the spleen. Macrophages with phagocytized bacteria would correlate with a bacterial infection. Macrophages without any inclusions would be a normal presentation on the differential and would not indicate a disease state.

Urine test strip positive for blood may indicate all, EXCEPT:

Meat diet Individuals consuming mostly meat diet will show acidic urine pH. Hematuria may be caused by glomerulonephritis, renal calculi, and pyelonephritis. Hemoglobinuria, on the other hand, can be caused by hemolytic anemia and severe burns. Myoglobinuria can be caused by muscular trauma, prolonged coma, drug abuse etc.

Which of the following will cause an acidic urine pH?

Meat-filled diet Acid urine is associated with:diet: meat-filled diet, cranberry ingestionhigh urine glucosediabetic ketoacidosisdiarrheastarvationemphysema Alkaline urine is associated with: metabolic alkalosis (vomiting, gastric lavage) diet: vegetarian, citrus diet, low carbohydrate diet kidney failure urinary tract infections respiratory alkalosis (hyperventilation) renal tubular acidosis presence of urease-producing bacteria (Proteus sp., Pseudomonas sp.) old specimens

On a Cytospin preparation from a pleural fluid specimen, 50% of the cells have the following characteristics: - uniform, regular arrangement- some cells resemble a "fried egg"- multiple nuclei- smooth nuclear outline and homogeneous chromatin- when present in clumps, there are clear spaces between the cells ("windows")

Mesothelial cells Mesothelial cells have a few key morphological features that aid in identification; notably, the "fried egg" appearance, homogenous chromatin, some have multiple nuclei, when present in clumps there are clear spaces between the cells ("windows"). None of the other cells listed have such characteristics.

The indicator(s) used in the pH test region of the chemical reagent strips for urine is/are:

Methyl red and bromthymol blue The indicator(s) used in the pH test region are methyl red and bromthymol blue. Typically, on most chemical reagent strips for urine pH, with an increase in urinary pH the indicator methyl red changes from red-orange (pH 4) to yellow (pH 6). If the pH is > 6, bromthymol blue turns the pad from yellow to green and blue (pH 9).

All of the following are urinalysis findings associated with nephrotic syndrome EXCEPT:

Mild proteinuria Heavy proteinuria, not mild proteinuria, is associated with nephrotic syndrome. Other urinalysis findings in nephrotic syndrome include hematuria, renal tubular epithelial cells, oval fat bodies, fat droplets, fatty casts, and waxy casts.q

The presence of Bence Jones protein in urine is associated with which of the following conditions?

Multiple myeloma Bence Jones protein is composed of monoclonal immunoglobulin light chains. Multiple myeloma is an immuno-proliferative disorder that causes a marked increase amount of monoclonal immunoglobulin light chains (Bence Jones protein) to be produced and excreted in the urine. Tuberculosis is not known to cause any changes in a patient's urine. It is a disease that impacts the lungs. UTIs commonly cause a positive nitrite and a positive leukocyte esterase result on the dipstick. Some bacteria are non-nitrite reducers (gram-positive organisms) and may not cause a positive nitrite result. Bence Jones proteins are not related to a UTI. Common urinalysis findings in patients with diabetes are positive glucose and ketones. Positive ketones are usually associated with Type 1 diabetes, but may also appear less commonly in Type 2 diabetes, low carbohydrate diets, and starvation.

Identify the predominant nucleated cell in this cerebrospinal fluid cytospin differential.

Nucleated red blood cells (NRBCs) The correct answer is NRBCs. The predominant nucleated cell in this image is NRBCs. There are neutrophils and metamyelocytes present in this image, but they are not predominant. There are no tumor cells present in this image.

Which of the following cells are considered abnormal and clinically significant on a CSF differential?

Myeloblast Myeloblasts are abnormal findings in a CSF differential and seen as a serious complication of acute leukemia. Ependymal, arachnoid mesothelial, and choroidal cells are not considered abnormal findings since they are tissue cells found in the areas surrounding the spinal fluid.

How should the production of a blue or purple color on the test pad of an Ictotest® be interpreted?

Negative for ketones The production of a blue or purple color on the test pad of an Ictotest® be interpreted as positive for bilirubin.

What is the primary functional unit of the kidney?

Nephron The nephron, the basic functional unit of the kidney, consists of a glomerulus, the proximal convoluted tubule, the loop of Henle, the distal convoluted tubule, and the excretory duct.

What type of white blood cell is seen MOST frequently in urine sediment with infections of the urinary system?

Neutrophil Neutrophils are typically increased in urinary bacterial infections. Eosinophils in urine sediment are usually associated with drug-induced interstitial nephritis. Lymphocytes and monocytes may be seen in the early stages of renal transplant rejection.

A semen sample for semen analysis should generally be received at the testing site within what period of time?

One hour It is recommended that a semen analysis sample be delivered within one hour to ensure accurate testing results. The semen specimen is examined under a microscope to determine the concentration, motility (movement), and morphology (appearance and shape) of the sperm. Since it is important to observe the sperm while they are still active, samples must be received for analysis within an hour.

To determine if xanthochromia is present in a cerebrospinal fluid sample, the sample must be centrifuged within:

One hour Xanthochromia is the pink, yellowish, or orange discoloration of the CSF mostly due to the presence of RBC degradation. If tubes are left to sit too long, the red cells can lyse causing hemolysis in the tube which can appear similar to xanthochromia.

All of the following are methods employed for measuring the specific gravity of urine, EXCEPT?

Osmolality Osmolality is dependent on the number of particles of solute in a unit of solution and is often measured by freezing point depression. Specific gravity is usually directly related to osmolality but is more easily measured. It provides a rough measure of the urine concentrating power of the kidney. The other methods are used to measure specific gravity in urine samples.

All of the following are directly involved in the production of semen EXCEPT?

Pituitary gland The structures involved in the production of semen include the prostate, the seminal vesicles, and the bulbourethral gland, along with the testes and epididymis. Semen is produced as a combination of secretions from the different regions of the male reproductive tract. Each fraction differs in chemical composition and function. Spermatozoa are produced in the testes. They mature in the epididymis. The testes also produce testosterone and inhibin. Fluid from the seminal vesicles accounts for approximately 70% of semen volume. The seminal vesicles are the source of fructose in semen. Fructose is used by the spermatozoa as an energy source. The prostate gland supplies about 20% of the volume of semen. Its fluids include acid phosphatase and proteolytic enzymes that lead to coagulation and subsequent liquefaction of semen. The prostate also contains most of the IgA found in semen. The bulbourethral gland produces mucoproteins that make up about 5% of the volume of semen. The pituitary gland is not directly involved in the production of semen; instead hormones are released which stimulate the production of sperm.

Parasites that may be found in urinary sediment include all of the following EXCEPT:

Plasmodium malariae Plasmodium malariae is the only parasite that is listed that could NOT potentially be seen in urine sediment. Plasmodium is a blood parasite. Both Enterobius vermicularis and Trichomonas vaginalis could potentially arrive in the urine as contaminants from other sources; Enterobius from fecal contamination and Trichomonas from vaginal secretions.Of the parasites that are listed, only Schistosoma haematobium is a true urinary tract parasite.

Which of the following is true about Bence-Jones protein when performing the heat precipitation test?

Precipitates between 40° and 60°C but redissolves at 100°C Bence-Jones protein is a protein that is excreted by persons with multiple myeloma, a myeloproliferative disorder of the immunoglobulin-producing plasma cells or Waldenstrom's macroglobulinemia. The protein, which is markedly elevated in blood serum, is filtered through the kidneys in quantities that exceed the tubular reabsorption capacity. Consequently, it is excreted in the urine. All suspected cases should have protein and immunoelectrophoresis performed on both serum and urine. The sulfosalicylic acid and dipstick methods are semiquantitative tests that are not specific for Bence-Jones proteins when tested individually. If the dipstick is negative but the sulfosalicylic acid test is positive, Bence-Jones proteins are suspected. The next step is to perform the heat precipitation test, Bence-Jones proteins precipitate between 40° and 60°C but redissolve at 100°C.

Cholesterol is used by the body for which of the following functions?

Precursor of hormone synthesis Cholesterol is a precursor of hormone synthesis. It is not a major source of fuel itself, but does facilitate triglyceride transport to serve the fuel needs of the body. Chylomicrons carry dietary triglycerides to the cells. Bicarbonate helps to maintain acid-base balance.

The image is a Wright-Giemsa stained smear (1000x) of cerebrospinal fluid (CSF). What is the identification of the cells that are indicated by the arrows?

Presumptive malignant cells The image is a Wright-Giemsa stained smear (1000x) of cerebrospinal fluid (CSF). What is the identification of the cells that are indicated by the arrows?

All of the following are primary functions of the kidney, EXCEPT?

Reabsorption of waste products Blood is filtered in the kidney, nutrients, water, and salts are reabsorbed while waste products are eliminated from the body by the urinary system. The kidney also helps regulate the acid-base balance in the body.

The kidneys perform all of the following functions EXCEPT:

Reabsorption of waste products One of the most prominent functions of the kidneys is the removal of unwanted substances from plasma. Waste products are not reabsorbed by the kidneys. The kidneys manage to control the body's pH by conserving bicarbonate ions and removing metabolic acids. The kidney has endocrine functions as it produces its own hormones, and as the target locus for hormones produced by other endocrine organs. The kidneys synthesize renin, erythropoietin, 1,25- dihydroxy vitamin D3, and prostaglandins. The kidney's water balance is regulated by the hormone AHD. In dehydration, the renal tubules reabsorb water at their maximal rate, resulting in the production of a small amount of maximally concentrated urine. In states of excess water, the tubules reabsorb water at only a minimal rate and it results in the excretion of a large amount of diluted urine.

Identify the urine sediments present in this image observed using brightfield microscopy.

Red blood cells This slide shows many red blood cells. Red blood cells (RBCs) are slightly smaller than WBCs and have a smooth, non-nucleated appearance. White blood cells have a rough appearance and contain granules and multilobed nuclei which fill out the cytoplasm of the cell. Squamous epithelial cells are the largest cells found in the urine sediment and can even be seen under low-power field. They may appear as clumps of cells and have a very large irregular-shaped cytoplasm with a prominent centrally located nucleus. Yeast cells can appear very similar to red blood cells in the urine at times. Yeast cells are usually oval and a bit smaller than red blood cells and can have a "budding" appearance. This morphology can aid in the differentiation between red cells and yeast. Acetic acid can be added to urine samples in order to lyse red blood cells and leave the remaining sediment intact. This is useful when attempting to differentiate between red cells and yeast.

The oxidation of hemoglobin to methemoglobin in acidic urine after several hours may cause which of the following color to produce?

Red to brown Red to Brown Urine: porphobilinogen, hematuria, myoglobinuria, etc. White: phosphates, other crystals Yellow: bilirubin, bile pigments Blue-green: Bacterial infections including urinary tract infection (UTI) by Pseudomonas species, and intestinal tract infections resulting in increased urinary indication.

A copper reduction method (e.g. Clinitest® or Benedict's) is performed on pediatric specimens in order to check for the presence of:

Reducing substances A copper reduction method (e.g. Clinitest® or Benedict's) is performed on pediatric specimens in order to check for the presence of reducing substances. This additional step is an easy way of screening for inborn metabolic problems, in particular, galactosemia.

All of the following are functions of cerebrospinal fluid, EXCEPT?

Regulate body metabolism. Cerebrospinal fluid has three main functions: Protect the brain and spinal cord from trauma. Supply nutrients to nervous system tissue. Remove waste products from cerebral metabolism.

Semi-automated and automated urine chemical reagent strip readers:

Remove subjectivity allowing for better reproducibility Semi-automated and automated urine chemical reagent strip readers remove subjectivity, associated with visual discrimination among colors, allowing for better reproducibility. This way, the laboratorians' results will be consistent while allowing for the interfacing of results into a laboratory information system.

At what temperature should the urine be prior to testing with the reagent strip method?

Room temperature Urine should be at room temperature prior to testing with the reagent strip method. Urine strip reactivity can increase with increased urine temperature, so the optimum temperature is 22-26oC or room temperature.

A cloudy, yellow-green synovial fluid with 122,000 WBCs which are predominantly neutrophils, and a decreased glucose, would be classified as:

Septic Feedback Clarity Color WBC/ µL Neutrophil % Glucose Non-inflammatory Clear Yellow <1000 <30 Similar to blood glucose Inflammatory Cloudy Yellow 2000-75000 >50 Low Crystal induced origin Cloudy Milky Up to 100,000 <70 Low Septic Cloudy Yellow-Green 50,000-100,000 >75 Low

How does ion concentration in the urine relate to specific gravity?

Specific gravity increases as ionic concentration increases. Urine-specific gravity increases as ionic concentration increases. If there were no solutes present, the specific gravity of urine would be 1.000, which is the same as pure water. Since all urine has some solutes present, a urine SG of 1.000 is not really possible. The upper limit of the test pad on a chemical reagent strip, which is typically 1.035, indicates concentrated urine, one with many solutes with a smaller amount of water.

The cell indicated by the arrow is a:

Squamous epithelial cell Large flat irregular squamous epithelial cells with a low nuclear to cytoplasmic ratio are generally found in the urine of females as a result of vaginal contamination. They are often in groups or clumps of cells. Transitional epithelial cells are smaller than the squamous epithelial cells and appear in several shapes including spherical, polyhedral, and caudate. They line the renal pelvis, calyces, ureters, and bladder and usually appear in the urine after invasive procedures such as catheterization. Renal tubular epithelial cells (RTEs) can vary in size and shape depending on their source. RTEs from the proximal convoluted tube tend to be larger, have a rectangular shape, and are called columnar or convoluted cells. Those from the distal convoluted tube are smaller and have a round or oval shape. Collecting duct RTEs have a cuboidal shape and unlike the other RTE types, they appear in large sheets of cells. Macrophages would be smaller than epithelial cells and may appear vacuolated.

A WBC differential count on CSF should be performed using the following technique:

Stained smear of a cytocentrifuged specimen

A patient has been diagnosed with an upper gastrointestinal bleed. Which of the following would be characteristic of this condition?

Stool much darker brown or black color Black or darker brown stools typically are a result of upper GI bleeding, iron therapy, and/or the ingestion of bismuth (antacids) and Charcoal. Red stools may be caused by a lower GI bleed, beets, food coloring, and Rifampin. Pale yellow, white, or gray stools are usually a result of a bile-duct obstruction or ingestion of Barium sulfate. Mucous or blood-streaked mucus stools are typically a result of dysentery, malignancy, or constipation.

Four tubes of CSF on the same patient were received in the laboratory. It was noted on the report that all four tubes contained visible blood. Which of the following is the best explanation for this finding?

Subarachnoid hemorrhage If the first tube of a spinal tap is bloody, then the remaining tubes should be observed for visible blood. If the tubes appear progressively clearer, then the blood is considered to be from a traumatic tap. If all tubes are uniformly bloody, the probable cause is a subarachnoid hemorrhage. Meningitis, although a serious disorder affecting the meninges of the spinal column, should not be the cause of the appearance of RBCs in any of the specimen tubes. The WBC count would be affected and should not precipitate the appearance of red blood cells. A warm autoimmune hemolytic anemia results in hemolysis, primarily extravascular, which should not affect the spinal fluid, which in normal conditions, does not contain blood cells of any form.

All of the following are quantitative methods for the determination of albumin EXCEPT?

Sulfosalicyclic acid precipitation The sulfosalicylic acid method is a semiquantitative method and not a quantitative method. It is also not specific for albumin. All of the others are quantitative methods for the determination of albumin.

Which acid is most frequently used to precipitate protein for confirmatory urinalysis tests?

Sulfosalicylic Sufosalicylic acid, or SSA, is used to precipitate protein in urinalysis to measure protein concentration with turbidity observations. Unlike the protein test on the dipstick, the SSA reaction will detect albumin and globulins and Bence-Jones proteins. This principle is based on the acidification of proteins which causes turbidity and can be measured based on protein concentration.

Which of the following would be the most appropriate method to confirm a positive protein from a urine dipstick:

Sulfosalicylic acid precipitation Protein in the urine can be confirmed using sulfosalicylic acid (SSA) precipitation. The SSA reagent is added to a small volume of urine. Acidification causes precipitation of protein in the sample, which is subjectively graded as trace, 1+, 2+, 3+ or 4+. SSA reaction will detect albumin, globulins, and Bence-Jones proteins.

The estimation of hyaluronic acid concentration by measurement of viscosity is useful in evaluating which type of fluid?

Synovial Hyaluronic acid is a substance found in the synovial (joint) fluid. This allows for the thicker consistency of the fluid for cushioning and protection from friction during movement.

What effect may bacterial contamination have on urine pH?

The bacteria may make the pH more alkaline. A urine pH above 8.0 may indicate that a specimen has been held non-preserved too long, which allows the multiplication of urea-splitting bacteria with a resultant increase in pH.

A patient suspected of a urinary tract infection has a negative nitrite test, but bacteria is present upon microscopic examination. What may have caused this discrepant result?

The bacteria present is not a nitrate-reducer. When a urine sample shows a negative nitrite test, but bacteria are present upon microscopic examination, the false-negative result could be caused by different possibilities such as: The bacteria that is present is not a nitrate-reducer. The urine was in the bladder for an insufficient amount of time (less than 4 hours) for nitrate to be reduced to nitrite. Lack of dietary nitrate resulting in inadequate nitrate levels in urine. Nitrate was further reduced to nitrogen interfering with the diazo reaction. Bacterial metabolism is inhibited by the presence of antibiotics. Large amounts of ascorbic acid present in urine, interfering with the diazo reaction.

All of the following crystals will normally be found in a urine specimen with a pH of 8.0, EXCEPT?

Uric acid Uric acid crystals are most commonly found in acidic urine; therefore, an alkaline urine with a pH of 8.0 would not have uric acid crystals present. All the other crystals listed are found in alkaline urine.

All of the following are true of Xanthochromia in cerebrospinal fluid, EXCEPT:

The clear appearance of CSF The clear appearance of CSF is normal. Xanthochromia is the pink, yellowish, or orange discoloration of the CSF mostly due to the presence of RBC degradation. Xanthochromia may be observed in the cerebrospinal fluid of premature infants because of immature liver function. Other Reasons for this include: Immaturity of the blood-brain barrier Elevated protein in CSF

Normal fecal specimens contain all of the following, EXCEPT:

The gastrointestinal tract contains resident microbiota in the Enterobacteriaceae family that may be identified in fecal specimens, such as E. coli. However, true pathogens are not normally present, including Salmonella enterica, Shigella, and Yersinia species. Electrolytes and urobilin are normally found in feces.

Define catheterization:

The insertion of a tube into a patient's bladder via the urethra to aid in urination. The insertion of a tube into a patient's bladder via the urethra to aid in urination is called catheterization. Mastectomy is the surgical removal of the breast. Blood collection should be avoided from the side where a mastectomy was performed due to the obstruction or stoppage of normal lymph flow (lymphostasis). Lymphostasis could change the composition of the blood, therefore creating invalid test results. The loss of consciousness resulting from insufficient blood flow to the brain is called syncope and is also known as fainting. The accumulation of interstitial fluid under the skin causing swelling is called edema. An edematous site should be avoided for venipuncture because the specimen obtained may be contaminated with interstitial fluid.

Which of the following casts might be found in the urine of a healthy individual after strenuous exercise?

The most common type of cast found in human urine is the hyaline cast. Low urine flow, concentrated urine, or an acidic environment can contribute to the formation of hyaline casts, and because of this, they may be seen in normal individuals in dehydration or vigorous exercise. The presence of renal tubular epithelial cell casts reflects tubular damage. Epithelial cell casts are seen in heavy metal and chemical or drug inducted toxicity, viral infections, and kidney transplant rejection. The presence of granular casts may have pathological or non-pathological significance. They can be seen during periods of strenuous exercise. In disease states, they can be occurring from the disintegration of cellular casts. They can also be found when granular casts remain longer in tubules, further disintegrate and looks like waxy casts. Waxy casts are indicative of urinary stasis and they can be found in people with chronic kidney failure.

The function of the cerebrospinal fluid includes all of the following EXCEPT:

The transmittance of neurologic impulses The cerebrospinal fluid does not transmit neurologic impulses. CSF does provide nutritional enrichment for the nervous tissue, removes metabolic waste products, and protects neurologic tissue from trauma.

These tubes of cerebrospinal fluid (CSF) arrive in the laboratory for evaluation. The tubes were numbered in the order in which they were obtained, with #1 being the first tube collected and #3 being the last tube collected. What may be indicated by the macroscopic appearance of the CSF?

Traumatic tap The appearance of the CSF suggests a traumatic tap. This is indicated by the fact that there is a decreasing amount of blood in the sequentially collected tubes; tube #1 contains visible red blood cells, but the amount of blood decreases in the other tubes. Normal CSF is clear and colorless. If the blood was the result of a subarachnoid hemorrhage, all three tubes would contain blood and the amount of blood in each tube would be consistent (unless a traumatic tap also occurred during the collection of the sample). Bacterial meningitis would not show decreasing amounts of red blood cells from tube #1 thru tube #3.

Which of the following crystals would most likely be found in normal ALKALINE urine?

Triple phosphate Triple phosphate crystals are found in normal alkaline urine. Amorphous urates and uric acid crystals are found in normal acid urine. While calcium oxalate crystals are rarely found in alkaline urine, they are more commonly found in acid urine.

Which of the following tests included on a urine chemical reagent strip would never be reported as negative?

Urobilinogen Urobilinogen is reported as normal, not negative. A normal urobilinogen result is approximate: 0.2-1.0 Ehr U/dL. Bilirubin is conjugated with glucuronic acid in the liver to become conjugated bilirubin, which is water-soluble. Conjugated bilirubin passes directly from the liver into the bile duct and then into the intestine where the bacteria reduce it into urobilinogen. Some urobilinogen is then reabsorbed from the intestine into the blood and then is filtered out by the glomerulus in the kidney. This is the reason a small amount of urobilinogen is normally present in urine.

Identify the urine sediment elements shown by the arrow: Type of Cast

Waxy cast Waxy casts appear smooth and homogeneous, and highly refractile. They are present in patients with severe renal failure and can be due to allograft rejection. Granular casts are composed of plasma protein aggregates and cellular remnants. They usually indicate renal parenchymal disease or allograft rejection. Granular casts appear as cylinders of coarse, or fine, highly refractive particles. Renal tubular epithelial (RTE) casts are caused by the sloughing of necrotic renal tubular cells due to advanced tubular destruction. They can be due to allograft rejection, acute tubular necrosis, and certain drugs. RTE cells are usually seen as part of the cast. Hyaline casts generally appear colorless, homogeneous, and transparent with rounded ends. They can also be seen as a result of dehydration, after diuretic therapy, in renal disease, and transiently as a result of exercise.

All of the following statements are true regarding the reagent strip test procedure, EXCEPT?

When visually reading the reagent strip, all test results can be read immediately after dipping the strip in the urine specimen. When visually reading the reagent strip, the results should be read at the prescribed time suggested by the manufacturer after dipping the strip in the urine specimen. Urine should NOT be centrifuged prior to dipping the reagent strip. Urine should be well mixed prior to dipping the reagent strip. Prolonged immersion may wash out test reagents.

In reference to semen analysis microscopic examination, differentiation, and enumeration of "round cells" which are often present in semen count are referred as:

White blood cells (WBCs) Round cells refer to WBCs or immature sperm cells in a semen sample. These cells can be differentiated on a stained smear, using 1000X magnification, or more precisely by performing a peroxidase assay. An increased number of WBCs present indicates inflammatory conditions associated with infection and poor sperm quality. Sperm vitality and seminal fluid fructose are the types of additional testing done when abnormalities are suspected in sperm morphology and functionality. The presence of Bacteria in the seminal analysis may be indicative of an infection.

What term is used to describe the color in these tubes of cerebrospinal fluid (CSF)?

Xanthochromia The term that is used to describe the color in these tubes of CSF is "xanthochromia." Xanthochromia is an abnormal color, usually yellow, orange, or pink, in the supernatant of the CSF sample. It may indicate that a subarachnoid hemorrhage (SAH) has occurred. Jaundice and icterus both describe a yellowing of the skin, mucous membranes, and eyes. Blood plasma/serum that is deep yellow is also described as icteric.

Cells seen in the microscopic examination of the urine of a 30-year-old female, which are smaller than RBC's but much the same shape, are probably:

Yeast cells Yeast cells can appear very similar to red blood cells in the urine at times. Yeast cells are usually oval and a bit smaller than red blood cells and can have a "budding" appearance. This morphology can aid in the differentiation between red cells and yeast. Acetic acid can be added to urine samples in order to lyse red blood cells and leave the remaining sediment intact. This is useful when attempting to differentiate between red cells and yeast. Lymphocytes, squamous epithelial cells, and trichomonas vaginalis are all larger than red blood cells.

Identify the urine sediment elements indicated by the arrows in this microscopic field.

Calcium oxalate crystals Calcium oxalate crystals can be seen in acid or neutral urine. They may also be present in normal urine. They characteristically occur as octahedral or envelope shapes. They can also be viewed as having a Maltese cross when one focuses up and down through the crystal. Uric acid crystals are variably shaped: they occur as flat diamond (four-sized), rhombic, lemon-shaped, or rarely hexagonal shapes with a yellowish or yellowish-brown coloration. They are present in acid urine. They are polarizable and show various colors when polarized. They may be present in normal urine. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners. They are soluble in hot alcohol and ether. Amorphous urates are found in acid urine and look like brick color or yellow/brown dust. Cystine crystals are present in acidic urine, are typically colorless, and have a characteristic hexagonal shape (also described as appearing similar to a benzene ring). These crystals are associated with cystinuria.

Identify the crystals in the image.

Cholesterol crystals These are cholesterol crystals. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners. Leucine crystals are associated with liver disease. They are found in acid to neutral pH urine specimens and are yellow in color. Concentric circles and radial striations are noted microscopically. Bilirubin crystals are yellow, needle-like crystals that may appear in clumps. They are found in acid urine and are associated with liver disease. Cystine crystals are present in acidic urine, are typically colorless, and have characteristic hexagonal shapes. These crystals are associated with cystinuria.

What is the identification of this cellular clump found in CSF? Note the presence of many similar-appearing nuclei without distinct lines of demarcation between cells.

Ependymal clump A key feature in identifying ependymal clumps is the presence of many similar-appearing nuclei without distinct lines of demarcation between cells. Basically, this cellular clump appears as one large cell, instead of many individual cells. On the other hand, choroid plexus clumps, mesothelial clumps, and macrophages do not display this "fused" morphology between cells. These types of cell clumps appear as individual cells gathered into a grouping. Cartilage cells usually occur singly. They are medium to large-sized cells with cytoplasm that stain wine red (with deep wine red nucleus). Tumor cells often occur in clumps. Cells in the clump are dissimilar, and some are multinucleated with variations in nuclear size. There are usually no clear spaces between the cells. Lymphoblasts can occur in CSF in acute lymphoblastic leukemia (ALL). They have the characteristics of lymphoblasts seen in blood with basophilic cytoplasm.

A patient with an infectious mononucleosis infection presents in the emergency room. Physicians order a spinal tap, which is immediately sent to the laboratory for review. What is the cell in the image below from this patient's cerebrospinal fluid sample?

Reactive Lymphocyte The cell depicted with the arrow in this image is an atypical (reactive) lymphocyte. These cells are commonly found in certain viral infections, especially infectious mononucleosis. Notice the larger size and abundant cytoplasm present in this lymphocyte. There is also apparent vacuolization, which is a key feature of atypical lymphocytes. The chromatin pattern of this cell, as well as the overall shape, color, and size, rules out the monocyte, macrophage, and mesothelial cell choices.

The element that is indicated by the arrow is a:

Red blood cell cast This is a red blood cell cast. Red blood cells (RBCs) can be identified within the matrix of the cast. The identification of the cast as a red blood cell cast is supported by the appearance of RBCs outside of the cast. Granular casts are composed of plasma protein aggregates and cellular remnants. Their presence in the urine may be of pathologic or nonpathologic significance. Granular casts appear as coarse or fine granules in a cast matrix. Hyaline casts generally appear colorless, homogeneous, and transparent with rounded ends. They can also be seen as a result of dehydration, after diuretic therapy, in renal disease, and transiently as a result of exercise. Renal tubular epithelial (RTE) casts are caused by the sloughing of necrotic renal tubular cells due to advanced tubular destruction. RTE cells are usually seen as part of the cast.

All of the following statements are TRUE regarding storing and handling of urine reagent strips if you are using a manual method (visually read reagent strip), EXCEPT:

Remove the cap of the test strip bottle and leave it off until testing is completed. The strips container should be kept tightly closed to prevent moisture contamination. To obtain qualitative results for each parameter, compare the color change observed on the strip to the color chart on the container. The pads on the strips contain a reagent area for testing. Chemical reactions occur when the strip is dipped in a urine sample. These reactions result in color changes that can be observed. The test strips should be stored at room temperature, but never refrigerated.

Identify the urine sediment element shown by the arrow:

Spermatozoa Spermatozoa cells have an oval head (body) and a long, thin tail, as see in the image. It is not uncommon to see spermatozoa in the urine of men due to nocturnal emissions, after epileptic convulsions, after coitus, and due to diseases of the genital organ. Yeast cells can appear very similar to red blood cells in the urine at times. However, yeast cells are usually oval and smaller than red blood cells and can have a "budding" appearance. This morphology can aid in the differentiation between red cells and yeast. In addition, acetic acid can be added to urine samples to lyse red blood cells and leave the remaining sediment intact. This is useful when attempting to differentiate between red cells and yeast. A cylindroid resembles a cast, with the exception that one end tapers out. Therefore, they are considered to have the same significance as casts. Trichomonas is the most common parasite found in urine. It is often the result of vaginal contamination. It is often mistaken for a white blood cell because of its size. However, characteristic motility (trichomonas is a flagellate organism) will help in its identification.

Which of the following statements is TRUE for specific gravity measured by the reagent strip method?

The reagent strip method is based on the relationship between ionic concentration and specific gravity. The reagent strip method is based on the relationship between ionic concentration and specific gravity. Urine specific gravity increases as ionic concentration increases. If there were no solutes present, the specific gravity of urine would be 1.000, which is the same as pure water. Since all urine has some solutes present, a urine SG of 1.000 is not really possible. The upper limit of the test pad on a chemical reagent strip, which is typically 1.035, indicates concentrated urine, one with many solutes with a smaller amount of water. The refractometer method is based on the fact that light is refracted in proportion to the amount of total solids dissolved in the urine. Unlike the refractometry method, the reagent strip method is NOT affected by the presence of x-ray contrast media in the urine specimen. When using the reagent strip method, an alkaline pH (6.5 or higher) would affect the specific gravity result by decreasing the reading.

All the following statements about the urine specimen are true EXCEPT:

The urine specimen should always be centrifuged before performing the chemical reagent strip testing. The intended answer is, "The urine specimen should always be centrifuged before performing the dipstick testing." Unfortunately, this is not the case. Urine specimens are not to be centrifuged before chemical reagent strip analysis. The urine specimen should be tested within two hours of collection if the specimen is stored at room temperature. It should be at room temperature and be well-mixed before performing the chemical reagent strip testing.

A cerebrospinal fluid sample was taken from an inpatient with severe neurological symptoms. The image shows a field from a cytospin preparation from this patient's fluid. What findings are present in this field?

Tumor cells This is a cytospin from the CSF of a patient with disseminated retinoblastoma demonstrating a large tumor cell clump with an occasional mitotic figure. Tumor cells should be reported for this sample. This sample should be sent for pathologist review prior to reporting these findings. Blast cells may appear in CSF and will look similar in CSF as they do in peripheral blood. Mesothelial cells form a layer of mesodermal cells in the pericardial sac. They are found in pleural and peritoneal fluids. Choroid plexus cells in a clump are neuroepithelial tissue cells that usually appear in a sheet formation.

What is the urinary system composed of?

Two kidneys, two ureters, one urinary bladder, and one urethra. The urinary system is composed of two kidneys, two ureters, one urinary bladder, and one urethra.

The nephron includes all of the following except:

Urethra

A test that can be used as a confirmatory test for urobilinogen is:

Watson-Schwartz Test Urine urobilinogen chemical reagent strip test results that are 2.0 Ehrlich units or greater can be confirmed using the Watson-Schwartz qualitative test. This test will differentiate between urobilinogen and porphobilinogen. Acetest® is used as a confirmatory test for ketones. Ictotest® is a confirmatory test for bilirubin. Clinitest is usually performed on infants up to two years old to help determine if galactose is found in the urine.

Which one of the following proteins in cerebrospinal fluid (CSF) is used to monitor the integrity of the blood-brain barrier?

Albumin The degree of permeability of the blood-brain barrier is evaluated by measuring the CSF albumin and comparing it with the serum albumin. Albumin is usually used as the reference protein for permeability because ordinarily it is not found to any great extent in the central nervous system.

Where does most cerebrospinal fluid (CSF) originate?

Choroid plexus Most CSF originates in the choroid plexus. The choroid plexus is composed of a mass of tiny blood vessels that are located in the third lateral and fourth ventricles. The remaining CSF, about 30%, is formed in other sites such as the subarachnoid space and the ependymal lining of the ventricles. Adults produce about 20 mL of CSF per hour. The fluid is reabsorbed at the same rate it is produced by the arachnoid granulations/villae back into the blood capillaries.

Identify the urine sediment element shown by the arrow.

Cylindroid The correct answer is cylindroid. Cylindroid is a type of varied morphology of hyaline casts. Hyaline casts consist of normal parallel sides and rounded ends. On the other hand, cylindroid forms have one tapered end and convoluted shapes that indicate the aging of the cast matrix. Mucus appears as single or clumped threads with a low refractive index. Fiber in a urine specimen from clothing and diapers can be confused with casts by inexperienced techs. To differentiate fiber artifacts from most casts, the specimen can be examined under polarized light. Fibers polarize while most casts other than fatty casts do not. Amorphous urates appear as yellow-brown granules. They could be in clusters that resemble granular casts. Upon refrigeration of urine sample, amorphous urates produce pink sediment.

When an unpreserved urine specimen cannot be cultured immediately, which storage method is most appropriate?

Stored in the refrigerator at 4° C for up to 24 hours When an unpreserved urine specimen cannot be cultured immediately it may be stored in the refrigerator at 4° C for up to 24 hours. After 24 hours of refrigeration, the culture results may not be accurate as some bacteria may not survive the extended time/temperature conditions. If the urine specimen is stored at room temperature for more than two hours without chemical preservative or placed in an incubator, the bacteria that may be already present will start to rapidly multiply and give falsely elevated culture results.

A sample of cerebrospinal fluid is diluted 1:100; the standard 9 squares of a hemocytometer were counted on each side for a total of 18 large squares.

2.06 x 104 In this example, we would use the standard manual WBC count equation. Cells/µL = # of cells counted x dilution / # of large squares counted x 0.1µL (chamber depth)In this case, Cells/µL = 370 x 100 / 18 x 0.1 Cells/µL = 37000 / 1.8 Cells/µL = 20556 or 2.06 x 104

The sediment from a freshly collected urine specimen is examined microscopically. In addition to bacteria, what other finding from the list below would further indicate the presence of a urinary tract infection (UTI)?

> 100 white blood cells (WBCs)/ HPF The presence of white blood cells, especially in large quantities as in this case, is very indicative of urinary tract infections as the white cells are migrating to the urinary tract to fight the bacterial infection. Hematuria, increased pH, and proteinuria are also usually present in UTIs.

Blast cells found in a spinal fluid differential are most likely associated with which of the following?

Acute Leukemia The presence of blast cells in the differential of spinal fluid is usually associated with acute leukemia.The presence of a high number and percentage of neutrophils can be associated with bacterial meningitis.The presence of a high number and percentage of lymphocytes can be associated with viral meningitis.Malignant cells found in spinal fluid can be associated with metastatic carcinomas.

A patient that is on a vegetarian diet will most likely have a(n):

Alkaline pH

A 3-year old girl was brought to the ER with a temperature of 103ºF, lethargy, and cervical rigidity. Three tubes of cloudy CSF were delivered to the Lab, and preliminary test results showed: A 3-year old girl was brought to the ER with a temperature of 103ºF, lethargy, and cervical rigidity. Three tubes of cloudy CSF were delivered to the Lab, and preliminary test results showed:

Bacterial meningitis Due to the elevated white blood cell count along with a strong percentage of neutrophils, a bacterial infection should be suspected. Though there are no organisms seen on the gram stain, a bacterial infection is still very possible as the bacterial count in the spinal fluid may be low. A viral meningitis would be more closely associated with an increased quantity of lymphocytes. Brain tumors and subdural hematomas would not be associated with these laboratory findings.

The predominant cells seen on the CSF smear in this illustration are indicative of:

Bacterial meningitis Intracellular microorganisms in the CSF cytospin are indicative of infection such as bacterial meningitis. A normal cerebral spinal fluid is clear and colorless with a consistency similar to water. Normal CSF should be mostly acellular by the manual chamber count. On the cytocentrifuged smear, a normal CSF will have less than 5 mononuclear cells/µL in adults. In viral meningitis, reactive lymphocytosis is present. Additionally, an increased number of lymphocytes is associated with fungal, tuberculous, and parasitic infections.

Fecal urobilinogen level may be markedly decreased because of:

Biliary obstruction In the intestines, bilirubin is converted to urobilinogen. Most urobilinogen, which gives feces their dark color, is excreted in the feces. An absence of bilirubin in the intestine, such as may occur with bile duct obstruction, blocks the conversion of bilirubin to urobilinogen, which causes clay-colored stools and a decreased fecal urobilinogen level.

The yellow clumped needles or granule-like crystals that are indicated by the arrows in the image are:

Bilirubin crystals These are bilirubin crystals. Bilirubin crystals are yellow, needle-like crystals that may appear in clumps, as indicated by the left arrow in this image. They are found in acid urine and are associated with liver disease. Leucine crystals are associated with liver disease and are found in acid to neutral pH urine specimens. One will notice the yellow color, concentric circles, and radial striations as characteristics of leucine crystals. Cystine crystals are present in acidic urine, are typically colorless, and have characteristic hexagonal shapes. These crystals are associated with cystinuria. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners.

Which of the following substances can cause a false positive result for blood on the urine chemical reagent strip?

Bleach in the collecting bottle The presence of bleach in the urine collection container can lead to a false positive blood result on the chemical reagent strip. Bleach can trigger the color change normally associated with the presence of red blood cells or hemoglobin. It is important to follow up with a microscopic analysis for confirmation of a true positive result. The presence of ascorbic acid, high levels of nitrites, or high specific gravity will not cause false-positive blood results on the chemical reagent strip.

All of the following are characteristic of an exudate effusion, EXCEPT:

Clear appearance Exudates are produced by conditions that involve the membranes of the particular cavity, including infections and malignancies. The appearance of an exudate effusion is cloudy, not clear. WBC of >1000 /mL, fluid serum protein ratio of > 0.5, and LD of >0.6 all are characteristics of exudate effusion.

Colorless hexagonal plate crystals seen in a urine specimen are MOST likely to indicate which of the following?

Cystinuria Cystine crystals, as seen in the image, are found in cystinuria, an inherited metabolic disorder in which cystine fails to be reabsorbed by the renal tubules. In gout, high levels of uric acid in the plasma cause uric acid to be pushed out into the urine. Uric acid crystals are also found in conditions/situations of increased purine and nucleic acids, as in cases of leukemia where patients are being treated with chemotherapy. There isn't one type of urine sediment associated with renal damage. Proteinuria and hematuria are common in renal damage along with urinary casts and renal tubular epithelial cells. Bilirubinuria is associated with liver disease. Bilirubin crystals may be seen when larger amounts of bilirubin are found in urine. In cases of liver disease, along with bilirubin and bilirubin crystals in the urine, tyrosine and leucine crystals may be present in the urine.

A cell count is ordered on a CSF sample that is bloody. Which of the following procedures would improve count accuracy?

Dilute the sample to minimize the number of red blood cells in the squares being counted. A total cell count could be performed initially by using saline, mixed by inversion, and loaded into the hemocytometer. If the sample were diluted with a mixture of acetic acid and crystal violet to minimize the number of RBCs, a more limited number of WBCs may not be visible in the counting area. This method is not recommended. Automated hematology cell counters usually do not have the low-end sensitivity needed to accurately count CSF samples. The use of electronic cell counters is not the normal practice for counting CSF cells due to high background counts and poor reproducibility of a low count.

Significantly increased levels of ketones are typically detected in the urine with all of the following conditions, EXCEPT?

Following a low-impact exercise routine Ketones are intermediate products of fat metabolism. Significantly increased levels of ketones are detected in the urine in diabetic acidosis, excessive carbohydrate loss, and starvation, among other conditions. Following a low-impact exercise routine, however, would not typically cause an increased urine ketones level.

Which of the following may be associated with acidic urinary pH?

High urine glucose Diabetes mellitus can cause acidic urine after controlling for dietary factors. Metabolic alkalosis will cause the urine to be alkaline. Loss of excessive electrolytes in consistent vomiting could be one of the factors. Renal tubular acidosis occurs when impaired kidneys function can't maintain acid-base balance which can lead to failure in excreting acid in the urine and reabsorbing bicarbonate. A diet high in citrus fruits and vegetables raises the pH and produces alkaline urine.

Identify the urine sediment element indicated by the arrow in the illustration:

Hyaline cast Hyaline casts generally appear colorless, homogeneous, and transparent with rounded ends. They can also be seen as a result of dehydration, after diuretic therapy, in renal disease, and transiently as a result of exercise. A mucus thread can be seen under phase-contrast or interference contrast microscopy and can resemble delicate ribbon strands that are generally transparent. They are normal in small numbers in the urine. A cylindroid resembles a cast, with the exception that one end tapers out. They are considered to have the same significance as casts. Waxy casts are yellow, gray, or colorless and very refractive. They resemble short broad casts with broken ends and cracked edges.

Which of the following methods may be employed to definitively identify Bence-Jones proteins?

Immunoelectrophoresis Bence-Jones protein is a protein that is excreted by persons with multiple myeloma, a myeloproliferative disorder of the immunoglobulin-producing plasma cells. The protein, which is markedly elevated in blood serum, is filtered through the kidneys in quantities that exceed the tubular reabsorption capacity. Consequently, it is excreted in the urine. All suspected cases shoud have protein and immunoelectrophoresis performed on both serum and urine. The sulfosalicylic acid and dipstick methods are semiquantitative tests which are not specific for Bence-Jones proteins when tested individually. If the dipstick is negative but the sulfosalicylic acid test is positive, Bence-Jones proteins are suspected. The next step is to performe the heat precipitation test, Bence-Jones proteins precipitate between 40° and 60°C but redissolve at 100°C.

Which one of the following statements concerning Tamm-Horsfall protein is FALSE?

It is the protein that is predominantly detected by a urine reagent strip test. Albumin, not Tamm-Horsfall, comprises the majority of the protein that is detected by the urine reagent strip test. Tamm-Horsfall protein is produced by the tubules. Tubular epithelial cells would have great difficulty functioning without it because it acts as a coating and lubricant in the tubules. Hyaline casts are formed by this protein in the distal tubule. Increased levels of protein in the urine (proteinuria) are an indicator of renal disease. The glomerular membrane prevents the passage of high molecular weight proteins including albumin (mol wt 69,000). The reagent test strip reaction is based on the "protein error of indicators" principle which means that the point of color change of pH indicators is different when protein is present versus when protein is not present. This phenomenon occurs because proteins act as hydrogen ion acceptors at a constant pH. Albumin is the main protein that is measured by the urine protein pad on the reagent strip because it contains more amino groups to accept hydrogen ions than other groups. Albumin is also the protein that is found in the highest concentrations in the body.

The crystals seen in this image are:

Leucine crystals These are leucine crystals and are associated with liver disease. They are found in acid to neutral pH urine specimens and are yellow in color. Notice the concentric circles and the radial striations. Bilirubin crystals are gold-orange, needle-like crystals that may appear in clumps. They are found in acid urine and are associated with liver disease. Cystine crystals are present in acidic urine, are typically colorless, and have a characteristic hexagonal shape (also described as appearing similar to a benzene ring). These crystals are associated with cystinuria. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners. They are soluble in hot alcohol and ether.

The image is a stained smear of cerebrospinal fluid. The cells present in this field may indicate what condition?

Leukemia with CNS involvement Allergic reactions, bacterial/viral meningitis do not cause the presence of blasts to be noted in the CSF. Leukemia with CNS involvement will show immature cells, similarly to the peripheral blood smear. An allergic reaction will show predominantly eosinophils. Bacterial meningitis will show mainly neutrophils. A broad spectrum of lymphocytes and monocytes would be present in a case of viral meningitis.

The image is a Wright-Giemsa stained smear (1000x) of cerebrospinal fluid (CSF). The arrows point to cells that may indicate which of the following conditions?

Leukemia with CNS involvementViral meningitis The arrows point to immature cells, the prominent nucleoli and large nucleus to cytoplasm ratio probably suggest blasts, which may indicate leukemia with CNS involvement. Blasts are not associated with allergic reactions (eosinophils), bacterial meningitis (neutrophils), or viral meningitis (lymphocytes).

A college student is treated in the hospital for suspected meningitis. Which cells should be identified in the cerebrospinal fluid (CSF) report for the cytospin field that is shown?

Lymphocytes The cell types which should be included in this report are lymphocytes. In viral meningitis the predominant cells that are seen are lymphocytes. They are also the predominant cells in normal adult cerebrospinal fluid, however, in viral meningitis, many of the lymphocytes will be reactive or atypical in their appearance. Monocytes are the predominant cells in the CSF of infants. Monocytes will have fine granules and an indented or folded nucleus. They will often spread across the slide and appear larger than lymphocytes, due to the centrifugation caused by the cytospin centrifuge. Blast cells are not normally found in the CSF. They are occasionally seen in patients with acute lymphoblastic leukemia. Blast cells will have fine nuclear chromatin, one or more nucleoli, and a high nuclear: cytoplasmic ratio. Plasma cells are not normally found in the CSF. They could be present in plasma cell leukemia or multiple myeloma due to a traumatic tap or a breakdown in the blood-brain barrier. Plasma cells have a round or oval eccentric nucleus, dark blue cytoplasm, and a clear zone adjacent to the nucleus (hof).

The following image is from a cytocentrifuged preparation of serous fluid. The arrow is pointing to which of the following:

Mesothelial cell Mesothelial cells are tissue cells that line the pleural, pericardial, and peritoneal cavities. They are normally sloughed from these membranes. Mesothelial cells appear as large, evenly stained cells with moderate to abundant light or dark blue cytoplasm. They may have one or more than one nucleus. The nucleus is smooth, round, and contains homogeneous chromatin. Large, uniform nucleoli may also be seen. Neutrophils and lymphocytes appear similar to their appearance in peripheral blood. However, they may have some artifacts due to cytocentrifugation, such as excess vacuoles, cytoplasmic projections, and hyperlobulation of the nucleus. Malignant cells typically appear as three-dimensional (cell-ball formation), large, irregular and uneven staining patterns, nuclear hyperchromasia, and unevenly distributed chromatin. Other findings may include bizarre vacuolization and cannibalism (one cell engulfing another).

All of the following conditions produce glycosuria, EXCEPT?

Myocardial infarction Diabetes mellitus, Fanconi's syndrome, and impaired tubular reabsorption/advanced kidney failure can cause glycosuria, myocardial infarction does not. Glycosuria is defined as the presence of glucose in the urine. It most commonly results from diabetes mellitus and impaired tubular reabsorption, but may also occur in Fanconi's syndrome, pregnancy, and in patients taking adrenocorticosteroids among other conditions.

The Sudan III stain is used to confirm the presence of:

Oval fat bodies Sudan III will selectively stain neutral fats bright red-orange. To confirm the presence of bacteria routinely follow up with urine culture is necessary. Examination under polarized light can frequently differentiate fibers and fatty casts. Mucus is a protein material produced by the glands, epithelial cells of the lower genitourinary tract, and renal tubular cells (RTE).

A urine specimen which was collected in a dark container, stored in the dark, has a pH of 7.5, and whose sample aliquot is wrapped in foil, is most likely being sent for:

Porphyrins Porphyrins are unstable when exposed to light. Urine specimens for porphyrin testing have to be collected in dark containers and stored away from light. Porphyrin concentrations can decrease as much as 50% if the specimens are exposed to light for 24 hours. An early morning specimen collected without preservatives and tested right away is the preferred method. If testing is delayed, the specimen should be stored in the dark for up to 48 hours at 4° C, or kept frozen at -20° C for at least a month.

To ensure precision and accuracy of the reagent strip tests used for chemical analysis of urine, it is necessary that:

Positive and negative controls are run on a daily basis and when a new bottle of test strips is opened Good laboratory practice states that to ensure that urinalysis instruments/procedures/reagents are functioning correctly, that positive and negative controls be run on a daily basis as well as when a new reagent strip bottle is opened.

Which of the following is an example of a macroscopic urinalysis abnormality?

Positive protein The macroscopic abnormalities are detected by the physical and chemical portions of the urinalysis. Obtaining a positive protein during the chemical portion of a urinalysis would be an example of a macroscopic abnormality. The presence of glitter cells, waxy casts, and red blood cell casts could only be determined by the microscopic examination of the urine sample.

Sulfosalicylic acid (SSA) can be used to confirm the result of which of the following tests included on a urine reagent strip?

Protein The SSA reaction is used to detect protein in the urine. Unlike the protein test on the dipstick, the SSA reaction will detect albumin and globulins, and Bence-Jones proteins. This principle is based on the acidification of proteins which causes turbidity and can be measured based on protein concentration present.

Sulfosalicylic acid (SSA) can be used to confirm the result of which of the following tests included on a urine chemical reagent strip?

Protein The SSA reaction is used to detect protein in the urine. Unlike the protein test on the urine chemical reagent strip, the SSA reaction will detect albumin and globulins, and Bence-Jones proteins. This principle is based on the acidification of proteins which causes turbidity and can be measured based on protein concentration present.

When performing a chemical examination of urine, a routine reagent strip test for protein is based on the principle of:

Protein-error-of-indicators The reagent strip test for protein is based on the protein-error-of-indicators principle to produce a visible colorimetric reaction. Precipitation by acid, copper reduction and ictotest tablets are the confirmatory methods for positive protein, glucose, and bilirubin.

Reabsorption in the kidneys primarily occurs in:

Proximal convoluted tubule Approximately 80% of all water and salts are reabsorbed in the proximal convoluted tubules.The glomerulus is a tuft of capillaries where blood filtration occurs. The glomerulus is surrounded by Bowman's capsule.The loop of Henle is the U-shaped (hairpin turn) portion of the tubules. While some reabsorption happens in the loop of Henle, because of its thinness (compared to the tubules), not as much water is reabsorbed here as is in the proximal convoluted tubule.

All of the following specimen collection methods should be used if urine cultures are also required, EXCEPT?

Routinely voided A routinely voided urine specimen is NOT acceptable for culture. An aseptic technique must be used to prevent contamination with urethral or vaginal bacteria that may cause misleading positive cultures. If the sample is to be cultured, the container must be sterile. The preferred method is the "clean catch" collection. The external genitalia is cleansed with a mild antiseptic solution. The first part of the urine stream is discarded while collecting only the midstream portion of the urine. Catheterized specimens and suprapubic aspiration specimens will also produce non-contaminated urine specimens, but they are more invasive and painful and should be used only as a last resort.

Which of the following test procedures is used to diagnose cystic fibrosis?

Sweat chloride test The sweat chloride test is considered the golden standard for the diagnosis of cystic fibrosis. It collects sweat from the patient and tests for the chloride concentration which can be up to five times higher for cystic fibrosis patients. A fecal occult blood test determines the presence of invisible quantities of blood in feces and assists in determining gastrointestinal tract lesions or colorectal cancer. Throat swabs are used to collect and test for the presence of streptococcal (strep) infections. There are usually two swabs rubbed together on the back of the patient's throat. One swab is used for the rapid strep test and the other is sent to the microbiology laboratory for culture. The diagnosis of peptic ulcers caused by Helicobacter pylori is done by collecting a breath sample and testing for urease, an enzyme that breaks down urea. Urease is not normally found in the stomach.

The image is a stained smear of cerebrospinal fluid. Which of the following statements is true about the cells shown at the right?

They line the arachnoid space. The cells seen here are ependymal cells which are found in the tissues lining the ventricles, the neural canal, and the arachnoid space. Notice the less distinct cell borders and the nucleoli.

These 3 tubes of cerebrospinal fluid (CSF) are delivered to the laboratory for analysis. The tube labeled #1 was the first tube collected. Which one of the tubes should be used by the hematology department for cell count and differential?

Tube #3 Hematology analysis is typically performed on the last tube collected to ensure that any peripheral blood that may have contaminated the sample during the lumbar puncture has cleared. In this case, only 3 tubes were collected. Therefore, tube #3 should be used for cell count and differential. The first tube collected should not be used for hematology analysis because of possible blood contamination from the lumbar puncture. Tube #1 is used for chemistry and immunology testing as any contamination (blood or bacteria) is removed by centrifuging the sample prior to analysis. Tube #2 is used for microbiology because any bacterial contamination introduced during the lumbar puncture should be washed into tube #1 and any blood contamination that remains will not affect microbiology testing. As a last resort, cell count and differential procedures can be performed on any tube, but it should be noted in the report. It is not standard operating procedure.

Name the crystals present on this slide. Crystal

Tyrosine These are tyrosine crystals, they are usually found in acid/neutral urine and appear as fine-needle clumps or rosettes. They are indicative of liver disease. Leucine crystals are associated with liver disease. They are found in acid to neutral pH urine specimens and are yellow in color. Concentric circles and radial striations are noted microscopically. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners. Cystine crystals are present in acidic urine, are typically colorless, and have a characteristic of hexagonal plates. These crystals are associated with cystinuria.

Name structure B from the image below:

Ureter

A yellow coloration found in fresh cerebrospinal fluid supernatant is termed:

Xanthochromia Xanthochromia usually implies subarachnoid hemorrhage of at least several hours duration, if in vitro lysis of red cells can be excluded. Xanthochromia is an abnormal color, usually yellow, orange, or pink, in the supernatant of the CSF sample.

Identify the majority of cells present in this urine slide.

Yeast Yeast is present on this slide. Several examples are indicated by the arrows. Yeast cells can appear very similar to red blood cells in the urine at times. Yeast cells are usually oval and a bit smaller than red blood cells and can have a "budding" appearance. This morphology can aid in the differentiation between red cells and yeast. Red blood cells are smooth, non-nucleated, biconcave cells. Acetic acid can be added to urine samples in order to lyse red blood cells and leave the remaining sediment intact. This is useful when attempting to differentiate between red cells and yeast. WBCs have a rough appearance and contain granules and multilobed nuclei which fill out the cytoplasm of the cell. Squamous epithelial cells are the largest cells found in the urine sediment and can even be seen under low-power field. They may appear as clumps of cells and have a very large irregular-shaped cytoplasm with a prominent centrally located nucleus.

"Xanthochromic" CSF means that the color of the CSF can be any of the following EXCEPT:

Blue Color can be seen in centrifuged cerebrospinal fluid (CSF) specimens and is generally due to the presence of hemoglobin from lysed red blood cells. Therefore, a blue color would not be produced from released hemoglobin but rather shades of pink and yellow. Pale orange or pale pink colors can be seen from 2-12 hours after a subarachnoid hemorrhage, and so the color should always be reported. The specimen could appear yellowish at about 12-24 hours after such a hemorrhage and should also be noted. However, other conditions, as well as a delay in processing can lead to false positives.

Prominent vacuolation involving the cytoplasm of abnormal lymphoblast-like cells seen in the peritoneal body fluid preparation shown is a distinctive feature of which disease?

Burkitt Lymphoma The correct answer here is Burkitt lymphoma. Prominent cytoplasmic vacuolation of Burkitt lymphoma cells helps laboratorians identify these cells in a cytospin preparation of body fluids. Hodgkin's lymphoma is identified with classic Reed-Sternberg cells and not cells with vacuoles. Hairy cell leukemia is an uncommon chronic lymphoproliferative disorder of the B-lymphocyte type. Hairy cell Leukemia is named such because of the fine, hair-like irregular cytoplasmic projections that are characteristic of the lymphocytes. Chronic lymphocytic leukemia can be identified with the presence of leukocytosis with a markedly increased number of mature lymphocytes and lymphocytosis.

A cerebrospinal fluid sample from a possible meningitis patient demonstrated a round, budding yeast of variable size on Gram stain. The specimen was cultured to routine fungal media without cycloheximide. The organism rapidly produced urease and demonstrated brown pigmented colonies on niger seed agar. The organism identification is:

Cryptococcus neoformans Cryptococcus neoformans is a significant human pathogen that has been associated with meningitis, pulmonary infections, and fungemia, especially in immunocompromised patients. Some of these isolates have the ability to produce a polysaccharide capsule that is visible with capsular stains or an India ink prep. The capsule may cause the colonies to be mucoid except on inhibitory mold agar. A presumptive identification may be made with a rapid positive urease test. Brown pigment colonies on niger seed agar have been sufficient for final identification. Candida albicans is a significant human pathogen as a cause of thrush, vulvovaginitis, respiratory infection, meningitis, and more. This organism produces small budding yeast with pseudohyphae and smooth, creamy, white colonies on fungal media. It produces urease but it is not rapid and it does not produce a pigment on niger seed agar. Malassezia furfur is more commonly known to cause skin infections but other infections may occur. Diagnosis is typically based on direct microscopic examination of skin scrapings. If the sample is cultured, the organism requires an over-lay with olive oil for growth. Colonies are smooth, creamy, and white but smaller than Candida albicans colonies. It does not produce brown colonies on niger seed agar. Trichosporon species cause skin infections and fungemia, especially in immunocompromised individuals. Direct examination demonstrates the presence of arthroconidia. The colonies have been described as dry, heaped, and powdery. It is also known to produce urease but it is not rapid. It does not produce brown-pigmented colonies on niger seed agar.

Which of the following is the recommended method for preparing a cerebrospinal fluid (CSF) sample for a differential count?

Cytocentrifugation A slide for microscopic examination of CSF should be made using a cytocentrifugation technique (cytospin). Alternate methods of slide preparation, such as concentration of cells by traditional centrifugation, manual smear methods, and counting chambers are not recommended as morphologies may not be maintained and sufficient cells may not be present on the slide for the accurate evaluation of the sample.

A urine specimen is received in the laboratory late in the afternoon. The specimen was collected early in the morning and was accidentally left in bright sunlight and at room temperature on a counter in the outpatient clinic. The test order is for urine bilirubin screening. Which of the following could occur as a result of the storage conditions?

False-negative test result Storage of the urine specimen in light for an extended period of time may cause a false-negative bilirubin result. Bilirubin is light-sensitive, so urine specimens should be protected from prolonged exposure to light. The specimen should be tested as soon as possible after collection. On standing, bilirubin, which has a goldish color, is oxidized to biliverdin, which is a green color. Many of the procedures used to detect bilirubin will not react with biliverdin, so false-negative results may occur if urine is not fresh when tested.

A physician obtains a peritoneal fluid sample by lavage on a patient who complained of fever and abdominal pain following an automobile accident. The fluid is analyzed in the laboratory. How should the sample shown in the image to the right be reported?

Neutrophils and bacteria In this image, there are intracellular bacteria inside of the neutrophils, a sign of bacterial infection; therefore, both of these observations should be reported. In addition, extracellular bacteria are also noted in the field. This finding should be included as well. Lymphocytes have round nuclei and may be associated with a viral infection. Eosinophils have large orange granules in the cytoplasm. Mesothelial cells, cells that line the peritoneal cavity, are large and may be multinucleated.

A 21-year-old visited her doctor. She mentioned dysuria, frequency and urgency of urination to her doctor. Which of the following urinalysis reagent strips tests would you expect to be positive for this patient based on her symptoms?

Nitrites Nitrites on the reagent strip provide a rapid screening test for the presence of urinary tract infection (UTI). Many UTIs are believed to start in the bladder as a result of external contamination and they can possibly progress upward through the ureters to the tubules, pelvis, and kidney. The nitrite test is valuable for detecting bladder infection. Ketones represent the product of fat metabolism. Increased fat metabolism is the inability to metabolize carbohydrates as it occurs in diabetes mellitus Blood positive on the reagent strip indicates hematuria or hemoglobinuria. Major causes of hematuria include renal calculi, glomerular disease, tumors, trauma, etc. Hepatitis and cirrhosis are common examples of conditions that produce liver damage, resulting in bilirubinuria.

What test can be used as a confirmatory test for proteinuria?

Sulfosalicylic acid test There are several precipitation methods for the determination of total protein in urine and other body fluids, including the measurement of turbidity when urinary proteins are mixed with an anionic organic acid such as sulfosalicylic acid. The reagent does not react equally with each protein fraction. It will produce four times more turbidity with albumin than with a-globulin.The Acetest is used to detect ketones. Sodium nitroprusside reacts with acetoacetic acid in an alkaline pH to form a purple color. If the reagent contains glycerin, then acetone is detected also. This method is used with the urine reagent strip and Acetest tablets.The ability of glucose to function as a reducing agent has been useful in the detection and quantitation of carbohydrates in body fluids. Benedict's and Fehling's reagents, which contain an alkaline solution of cupric ions stabilized by citrate or tartrate, respectively have been used to detect reducing agents in urine and other body fluids.

All of the following statements are true regarding urinalysis reagent strips EXCEPT?

The expiration date on the bottle does not matter, as long as the controls are acceptable. The expiration date for any reagent used in the clinical laboratory always matters. It is never acceptable to use a urinalysis dipstick that is expired. Expiration dates should be check daily as part of quality control to ensure that patients are not tested with expired reagent strips. Prolonged immersion in the urine specimen may wash out reagents rendering erroneous results. To maintain reagent viability, strips should be stored in a way that prevents exposure to moisture. Most manufacturers include a desiccant in the container to absorb any moisture that could render the strips inactive. Various test results on the reagent strip are to be read at different times. Manufacturer's recommendations should always be followed.

Which of the following statements is TRUE for specific gravity measured by the urine chemical reagent strip method?

The urine chemical reagent strip method is not affected by the presence of x-ray contrast media in the urine specimen. Unlike the refractometry method, the reagent strip method is NOT affected by the presence of x-ray contrast media in the urine specimen. The reagent strip method is based on the relationship between ionic concentration and specific gravity. Urine specific gravity increases as ionic concentration increases. If there were no solutes present, the specific gravity of urine would be 1.000, which is the same as pure water. Since all urine has some solutes present, a urine SG of 1.000 is not really possible. The upper limit of the test pad on a chemical reagent strip, which is typically 1.035, indicates concentrated urine, one with many solutes with a smaller amount of water. A high concentration of protein increases the specific gravity readings on the reagent strip as a result of interactions between the strip and protein anions. When using the reagent strip method, an alkaline pH (6.5 or higher) would affect the specific gravity result by decreasing the reading. The refractometer method is based on the fact that light is refracted in proportion to the amount of total solids dissolved in the urine.

Identify the urine sediment elements indicated by the arrow in the illustration:

Triple phosphate crystals Triple phosphate crystals appear as colorless prisms with 3 to 6 sides and oblique ends or "feathery sleeves." They have been described as "coffin lid shaped" and can normally occur in alkaline urine. They may indicate the presence of an infection. Cholesterol crystals appear in acid urine as large, flat, transparent plates with notched corners. They are soluble in hot alcohol and ether. Amorphous urate crystals are found in acid urine and resemble brick or yellow/brown dust under the microscope. Ammonium biurate crystals appear yellow to brown spherical bodies with long irregular spicules, known as "thorn apples". They can occasionally be identified in the alkaline urine of healthy patients, but can also be associated with specimens that are old or not stored properly.

The laboratory department that performs physical, chemical, and microscopic evaluation of urine is called:

Urinalysis (UA) Urinalysis (UA) is the laboratory department that performs the physical, chemical, and microscopic evaluation of urine. Clinical Chemistry is the laboratory department that performs most laboratory tests, which include quantitative analytical procedures on various body fluids. This department may have sub-sections such as Special Chemistry, Toxicology, Therapeutic Drug Monitoring, and Molecular Diagnostics. Urology is not one of the clinical laboratory departments. It is the branch of medicine that focuses on surgical and medical diseases of the male and female urinary tract system and the male reproductive organs. Microbiology is the laboratory department that cultures and identifies the presence of microorganisms from body fluids and tissues. This department may have sub-sections such as Bacteriology, Virology, Parasitology, Mycology, and Mycobacteriology.

A patient presents to the emergency room with severe headaches, nausea, and vomiting. CSF chemistry results are as follows: Protein - 74 mg/dL (15-45 mg/dL) Glucose - 53 mg/dL (40-85 mg/dL) Based on the patient's complaints and the above laboratory results what is the most probable condition?

Viral Meningitis The correct answer here is viral meningitis with an increased protein and normal glucose levels. Further testing with serology, polymerase chain reaction, and viral culture could be used to determine the cause of the patient's problems. Fungal meningitis laboratory results will show a normal protein level and a normal to decreased glucose level. Further testing to determine a fungal meningitis infection includes latex agglutination and positive fungal growth on cultures. Bacterial meningitis will present with markedly decreased glucose and increased protein results. Bacterial organisms would most likely be seen upon Gram stain of the CSF fluid. A traumatic tap would be visible from the specimens received in the laboratory and if possible should not be used to diagnose a patient.