Urinalysis MediaLab 1-3
The volume of urine recommended for centrifugation for a microscopic examination is: - 1 - 3 mL - 10 - 15 mL - 15 - 20 mL - Volume is not important
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.
Pleural fluid was sent to the laboratory for a WBC count. The specimen was NOT diluted. WBCs in 5 large squares were counted in each side of the hemacytometer. The number of WBCs counted were as follows: Top counting chamber: 35 cells total (in 5 large squares) Bottom counting chamber: 33 cells total (in 5 large squares) Based on the information provided above, calculate the total WBC count. - 34 cells/mm - 33.4 cells/mm^3 - 3680 cells/mm^3 - 68 cells/mm^3
68 cells/mm^3 The calculation of the cell count is based on the formula: Total cells/µL = (total number of cells counted x dilution factor)/(total number of squares counted x volume of each square) Each large square has a length of 1mm, width of 1mm and a depth of 0.1mm Thus, the volume of each large square is 1mm x 1mm x 0.1mm = 0.1mm^3 In this example, we would calculate: total cells/µL = (68 cells)/(10 x 0.1mm3) 68 cells/mm3 or 68 cells/µL
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: WBC: 4,500/µL Differential: 88% neutrophils & 12% lymphocytes Glucose: 15 mg/dL Protein: 140 mg/dL Gram stain: No organisms observed From these results, what preliminary diagnosis SHOULD the physician consider? - Brain tumor - Bacterial meningitis - Viral meningitis - Subdural hematoma
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.
All of the following white blood cells would produce a positive leukocyte esterase test on the urine chemical reagent strip, EXCEPT? - Neutrophils - Eosinophils - Basophils - Lymphocytes
Lymphocyte Leukocyte esterase is an enzyme present in most granulocytic white blood cells (neutrophils, eosinophils, basophils) and monocytes, but is not found in the lymphocytes or red blood cells. When the number of granulocytes in the urine increases significantly (more than 0-2 per field), this screening test pad will become positive on the chemical reagent strip. The presence of lymphocytes will not produce a positive leukocyte esterase test since lymphocytes do not contain leukocyte esterase.
All of the following crystals will normally be found in a urine specimen with a pH of 8.0, EXCEPT? - Ammonium biurates - Triple phosphates - Calcium carbonates - Uric acid
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 urinalysis findings may correlate with the presence of a yeast infection, EXCEPT: - Presence of glucose - White blood cells (WBCs) - Turbid urine - 3+ red blood cells (RBCs)
3+ red blood cells (RBCs) The presence of RBCs in the urine is associated with damage to the glomerular membrane or vascular injury within 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.
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 RBC 2-4 WBC 2-5 granular casts 2-5 hyaline casts 0-2 RBC casts few epithelial cells Based on the urinalysis report above, the MOST probable diagnosis of this patient's condition is: - Acute glomerulonephritis - Acute pyelonephritis - Acute cystitis - Nephrotic syndrome
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.
A microscopic examination of a normal urine pH 8.0 shows 2+ yellow-brown thorny spheres which are MOST probably: - Ammonium biurate crystals - Waxy casts - Amorphous urate crystals - Crenated red cells
Ammonium biurate crystals Ammonium biurate crystals appear as 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 which are old or not stored properly.
Detection of a fruity odor in a fresh urine sample may be indicative of all of the following EXCEPT: - Starvation - Malabsorption - Bacterial infection - Diabetes mellitus
Bacterial infection Conditions such as starvation, malabsorption, and diabetes mellitus can lead to an increase of ketones in the urine, giving the urine a "fruity", sweet type of odor.
A urine specimen produced yellow foam when shaken. What is the is the cause of the yellow foam? - Phosphates - Bilirubin - Normal - Red blood cells
Bilirubin Yellow foam- presence of bilirubin White precipitate upon refrigeration- presence of phosphates Clear/straw- Normal Pink- presence of red blood cells visible microscopically
Structure that holds urine - kidney - ureter - bladder - urethra
Bladder
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? - Diarrhea - Constipation - Inflammation of the intestinal wall - Bowel obstruction
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 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.
Homogentisic acid in urine will cause urine to be which of the following colors? - Green - Pink - Port-wine - Brown/black
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 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.
Which of the following would be the most characteristic finding in synovial fluid in a case of pseudogout? - Monosodium urate crystals - Calcium pyrophosphate crystals - Macrophage infiltration - Mixed RBC/WBC infiltration
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.
Identify the crystals in the image. - Leucine crystals - Cholesterol crystals - Bilirubin crystals - Cystine crystals
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 the 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 a characteristic hexagonal shapes. These crystals are associated with cystinuria.
A urine production of less than 400 mL/day is: - Consistent with normal renal function and water balance - Termed isosthenuria - Defined as oliguria - Associated with diabetes mellitus
Defined as oliguria Oliguria is defined as the production of a decreased amount of urine. This can be defined as a daily urine production of less than 400 mL. Normal urine production is between 1,200 to 1,500 mL and it can range from 600 to 2,000 mL. Isostenuria is a condition that produces urine with a specific gravity of 1.010 due to impaired renal tubular function. Diabetes mellitus produces urine volumes of >2500 mL/day.
Which of the following conditions is associated with a positive ketone test on the urine test strip? - Renal calculi - Diabetes mellitus - Hepatitis/cirrhosis - Urinary tract infection
Diabetes mellitus Findings of ketones on the urine test strip is 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.
All of the following are types of epithelial cells that line the genitourinary system EXCEPT: - Squamous - Cuboidal - Transitional - Flattened cells
Flattened cells There are no epithelial cells lining the genitourinary system named flattened cells. Squamous epithelial cells line the distal urethra, cuboidal cells are renal tubular epithelial (RTE) cells that line the collecting ducts, and transitional epithelial cells line the entire urinary tract except for the distal urethra.
The technologist in the urinalysis department received a sample for a microscopic examination. The image to the right shows the microscopic urinalysis. Which of the following conditions below would most closely match this patient's microscopic urinalysis morphology? - Diabetes mellitus - Glomerulonephritis - Yeast infection - Pyuria
Glomerulonephritis Glomerulonephritis is a type of kidney disease in which the glomerulus (filters waste and fluids from the blood) is damaged. Damage to the glomeruli causes blood and protein to be lost in the urine. Hence, the image shows the presence of red blood cells. Diabetes mellitus, yeast infections, and pyruria are not associated with red blood cells in the urine.
Viscosity of synovial fluid is due to synoviocyte secretion of mucopolysaccharide, which contains: - Acid phosphatase - Phosphatidyl glycerol - Hyaluronic acid - Lecithin
Hyaluronic acid Normal viscosity of synovial fluid comes from 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 coagulation and liquefaction of semen. Phosphatidyl glycerol and lecithin are lung surfactants present in amniotic fluid that serve as indicators of fetal lung maturity.
Which of the following methods may be employed to definitively identify Bence-Jones proteins? - Immunoelectrophoresis - Sulfosalicyclic acid precipitation - Heat precipitation at 40-60 C - Urine dipstick
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 of the following can cause a false positive result for ketones? - L-Dopa metabolites - Lightly pigmented urine - Using a freshly collected urine specimen - Presence of bacteria
L-Dopa metabolites L-Dopa metabolites or medications containing sulfhydryl groups may result in a false positive ketone test. A fresh specimen is advisable to prevent false reagent strip results. The presence of lightly pigmented urine and bacteria have not been shown to interfere with ketone reagent strip results.
All of the following crystals are found in normal urine, EXCEPT? - Triple phosphate - Ammonium biurate - Calcium oxalate - Leucine
Leucine Calcium oxalates can be found in normal urine in 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.
What are the MAIN functions of the distal convoluted tubules? - Balance hydrogen ions and keep the body pH at 6.8 - Control aldosterone production and ammonia reabsorption - Excrete various antibiotics and uric acid - Maintain water-electrolyte and acid-base balances
Maintain water-electrolyte and acid-base balances The main functions of the distal convoluted tubules are to maintain water-electrolyte and acid-base balances. These functions are controlled by antidiuretic hormone (ADH) and aldosterone.
After reviewing this cytospin from a pleural fluid, identify the cells that would be the appropriate to report? - Macrophages, neutrophils and red blood cells - Mesothelial cells, neutrophils and red blood cells - Tumor cells, neutrophils and red blood cells - Plasma cells, neutrophils and red blood cells.
Mesothelial cells, neutrophils and red blood cells The major cells present are mesothelial cells in a clump, which is consistent with a patient with pneumonia. There are also segmented neutrophils and red blood cells present as well in the background. Macrophages are monocytes that have phagocytized materials inside the cells. Tumor cells or neoplastic cells can be found in loosely joined clusters. Cytoplasmic vacuoles are frequently present. The nuclei tend to be larger with irregular nuclei. Plasma cells have a round, eccentrically placed nucleus with deeply basophilic cytoplasm with a lighter staining paranuclear area. Plasma cells are slightly smaller than mesothelial cells.
Glitter cell is a term used to describe a specific type of: - Ketone body - Oval fat body - Bacteria - Neutrophil
Neutrophil Neutrophils are the most predominant WBC found in the urine sediment. Neutrophils exposed to hypotonic urine absorb water and swell, and the granules exhibit Brownian motion resulting in a sparkling appearance which referred to as glitter cells. Ketones can be positive in urine when your cells don't get enough carbohydrates and use non-carbohydrate compounds such as fats and proteins for energy. Oval fat bodies are lipid containing renal tubular epithelial cells(RTE). The presence of bacteria can be indicative of either lower or upper urinary tract infection (UTI).
How should the production of a blue or purple color on the test pad of an Ictotest® be interpreted? - Positive for bilirubin - Positive for ketones - Negative for bilirubin - Negative for ketones
Positive for bilirubin The production of a blue or purple color on the test pad of an Ictotest® be interpreted as positive for bilirubin.
When preparing a slide for morphologic examination, what is the reason for adding a drop of albumin to the cerebrospinal fluid (CSF) sample prior to cytocentrifugation? - Enhance staining of the elements. - Preserve the integrity of the cells. - Increases the fluid volume so that cells will form a monolayer on the slide. - Dilute the sample
Preserve the integrity of the cells. The addition of a drop of 30% albumin helps to preserve the integrity and morphology of the cells in the hypotonic CSF. Albumin is not used to enhance the stain or dilute the sample. The cytocentrifugation process distributes the cellular elements in a monolayer.
What effect may bacterial contamination have on urine pH? - The bacteria may make the pH more alkaline. - The bacteria may make the pH more acidic. - The bacteria would not affect urine pH. - The bacteria will keep the pH neutral.
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 multiplication of urea-splitting bacteria with resultant increase in pH.
A urine specimen was collected at 6:00 a.m. and remained at room temperature until it was received in the laboratory at 3:30 p.m. How may the pH of the specimen be affected by the extended time at room temperature if bacteria are present in the specimen? - The pH may become more acidic. - The pH may become more alkaline. - The pH will become neutral. - The pH would probably not be affected.
The pH may become more alkaline. In this case, the pH may become more alkaline, perhaps above 8.0, if the bacteria in the sample are proliferating during the extended room-temperature wait time.
A negative glucose oxidase test and a positive test for reducing sugars in urine indicates: - True glycosuria - A false-negative glucose oxidation reaction - The presence of a non-glucose reducing sugar such as galactose - These results are normal
The presence of a non-glucose reducing sugar such as galactose A negative glucose oxidase test and a positive test for reducing sugars in urine indicates the presence of a non-glucose reducing sugar such as galactose, fructose, glyceraldehyde, etc. This is the reason that certain patient populations such as infants require additional confirmatory sugar testing on their urine samples.
A urine concentration test was performed on a patient after fluid deprivation period with the following findings: After 12 hours Urine Osmolality = 850 mOsm/KgAfter 16 hours Urine Osmolality = 850 mOsm/Kg What do these results indicate? - This represents normal kidney function. - This represents loss of tubular function and concentrating ability. - This represents a laboratory error, as these results are not medically possible. - These results represent end stage renal disease.
This represents normal kidney function. A urine osmolality of 800 mOsm or higher is considered normal when patients were deprived of fluid for 12 hrs. A concentration test is used to determine the ability of the tubules to reabsorb the essential salt and water that have been non-selectively filtered by glomerulus. The loss of tubular reabsorption capability is often the first function affected in renal disease.
What is the purpose of the sweat chloride test? - Is a noninvasive way to collect and test for DNA. - To aid in the diagnosis of streptococcal infections. - To help diagnose peptic ulcers due to Helicobacter pylori. - To help diagnose cystic fibrosis.
To help diagnose cystic fibrosis. The sweat chloride test is considered as 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. Buccal swabs are a noninvasive way used to collect DNA samples for testing. 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 Helycobacter pylori is done by collecting a breath sample and teasting for urease, an enzyme that breaks down urea. Urease is not normally found in the stomach.
The nephron includes all of the following except: - Urethra - Glomerulus - Loop of Henle - Proximal convoluted tubule
Urethra 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.
Which of the following casts is characteristically associated with acute pyelonephritis? - Red cell - White cell - Fatty - Waxy
White cell White cell casts are closely associated with acute pyelonephritis since white blood cells are drawn to the infection and inflammation of the kidney (definition of pyelonephritis) and are encased into casts which slough off into the urine. Red cell casts are indicative of glomerular damage and can be seen in various conditions, but most often nephritic syndromes. Fatty casts are most commonly seen in nephrotic syndromes. Waxy casts are indicative of extreme urine stasis and are most commonly associated with chronic renal failure.
Which of the following casts is characteristically associated with acute pyelonephritis? - Red cell - White cell - Fatty - Waxy
White cell White cell casts are closely associated with acute pyelonephritis since white blood cells are drawn to the infection and inflammation of the kidney (definition of pyelonephritis) and are encased into casts which slough off into the urine. Red cell casts are indicative of glomerular damage and can be seen in various conditions, but most often nephritic syndromes. Fatty casts are most commonly seen in nephrotic syndromes. Waxy casts are indicative of extreme urine stasis and are most commonly associated with chronic renal failure.
In a patient with acute glomerulonephritis you would expect to find all of the following in the urine EXCEPT: - protein - RBCs - RBC casts - Yeast
Yeast Yeast would not be an expected finding in a patient with acute glomerulonephritis. However, the presence of red blood cells, red blood cell casts, and protein are generally indicated when there is glomerular injury, or hemorrhage within the kidney.
This species of Candida accounts for around 20 percent of urinary yeast isolates. - Candida albicans - Candida glabrata - Candida krusei - Candida tropicalis
Candida glabrata Candida glabrata is the second most common Candida species to cause disease (Candida albicans is the most common). In urinary yeast isolates, it is identified about 20 percent of the time. Infections tend to be aggressive and difficult to treat with traditional antifungal therapy. It has different sugar assimilation patterns than Candida albicans, notably rapid assimilation of trehalose, so it can easily be differentiated. Candida krusei and Candida tropicalis are seen in immunocompromised patients, and cause nosocomial infections.
Which of the following are characteristics of normal CSF? - Clear - Turbid - Pink to yellow tinge - Clotted
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 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 urine - Concentration at which reabsorption first occurs - Concentration at which kidney can no longer filter the blood - Concentration at which kidney failure begins
Concentration at which a substance in the blood spills into 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 - Ortho-toluidine oxidation - Diazotization of sugars - Enzyme reaction
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.
A 62-year-old man drank an unknown liquid in a suicide attempt, and his urine contained crystals similar in shape to those shown in this image. This man MOST likely ingested: - Methanol - Isopropanol - Ethylene glycol - Ethanol
Ethylene glycol The crystals that are seen in the urine are monohydrate calcium oxalate crystals. Oxalic acid, a byproduct of ethylene glycol (antifreeze) metabolism, combines with calcium in the body to form monohydrate calcium oxalate crystals, as shown in the accompanying image. Accidental poisoning with ethylene glycol occurs most of the times in young children and pets. This is because it is a sweet tasting compound and if left uncovered in an easily reachable place it can be very tempting to consume.
When an automated or semi-automated method is used to read urine reagent strips, quality control testing must be performed at least: - Once a week. - Once per month. - With each new instrument operator. - Every day of patient testing and when a new bottle is opened.
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 are opened, when the results that are obtained are questionable, or when the integrity of the reagent strips are 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.
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? - Reactive mesothelial cells - Lymphocytes and Blasts - Monocytes - Reactive Lymphocytes
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 yeast cells - Lyse the red blood cells - Dissolve the oil droplets - Crenate the red blood cells
Lyse the red blood 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, yeast, or fat droplets. Once the red cells are lysed, polarized light can help to differentiate yeast from oil droplets, as oil or fat droplets will refract with a characteristic maltese cross shape.
The image is a stained smear of cerebrospinal fluid. The cell in this slide could be caused by what condition? - Viral meningitis - Allergic reaction - Cerebral hemorrhage - Metastasis
Metastasis The nucleus in this cell is abnormal and appears to have divided. This finding correlates with the presence of metastasis in the CSF. A broad spectrum of lymphocytes and monocytes would be present in a case of viral meningitis. An allergic reaction will show predominantly eosinophils. Cerebral hemorrhage would show predominantly RBCs.
All of the following conditions produce glycosuria, EXCEPT? - Diabetes mellitus - Fanconi's syndrome - Impaired tubular reabsorption/advanced kidney failure - Myocardial infarction
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.
What is the primary functional unit of the kidney? - ureter - glomerulus - nephron - distal convoluted tubule
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.
A 41-year-old man is admitted to the hospital complaining of a decreased frequency of urination, a constant bloated feeling, weight gain, and mild edema of the ankles and eyes. CHEMISTRY RESULTS: Color: pale yellow Clarity: clear pH: 5.0 Sp. Gravity: 1.010 Glucose: 2+ Ketones: negative Protein- 3+ Blood: moderate Bilirubin: negative Bacteria: negative Urobilinogen: normal Nitrate: negative **A large amount of white foam was noted. MICROSCOPIC RESULTS: RBCs: 0-2 WBCs: 0-2 Casts: 2-5 hyaline, 0-3 fatty casts, 0-2 waxy casts Few transitional epithelial cells Few oval fat bodies Based on the urinalysis report above, the MOST probable diagnosis is: - Acute pyelonephritis - Nephrotic syndrome - Acute glomerulonephritis - Lipiduria of unknown etiology
Nephrotic syndrome Nephrotic syndrome would best match the clinical symptoms and laboratory findings. Nephrotic syndrome is caused by damage to the kidneys, especially the basement membrane of the glomerulus; which causes abnormal excretion of protein and red blood cells in the urine. Fats are also present in the urine in most cases. A foamy appearance of the urine is a key characteristic of this condition. Clinical symptoms include: Swelling Weight gain from fluid retention Poor appetite High blood pressure
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? - Ketones - Blood - Bilirubin - Nitrites
Nitrites Nitrites on the reagent strip provides 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 it 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. An 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.
Sulfosalicylic acid (SSA) can be used to confirm the result of which of the following tests included on a urine chemical reagent strip? - Protein - Glucose - Bilirubin - Urobilinogen
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.
Semi-automated and automated urine chemical reagent strip readers: - Increase the sensitivity of the urine dipsticks - Increase the specificity of the urine dipsticks - Remove subjectivity allowing for better reproducibility - Guarantee the sensitivity and specificity of urine dipsticks
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.
Which of the following cells when found upon microscopic examination of the urine would be most indicative of kidney disease: - WBCs and bacteria - Renal tubular epithelial cells - Squamous epithelial cells - RBCs
Renal tubular epithelial cells Renal tubular epithelial cells are frequently seen in patients with acute renal tubular necrosis. They are most easily recognized when they form casts. WBCs and bacteria may be indicative of a urinary tract infection. Squamous epithelial cells are the largest cells found in urine sediment and are normally shed from the lower linings of urethra. They typically do not have clinical significance. RBCs are seen due to vascular injury withing the GI tract or due to damage to the glomerular membrane.
How does ion concentration in the urine relate to specific gravity? - Specific gravity increases as ionic concentration increases. - Specific gravity decreases as ionic concentration increases. - There is no relationship between SG and ionic concentration. - Specific gravity stays the same regardless of the ionic concentration.
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 a concentrated urine, one with many solutes with a smaller amount of water.
Which of the following best defines specific gravity: - Weight - Volume - Density - Density of a solution compared to density of water
Specific gravity is the ratio of the mass of a solution to the mass of an equal volume of water. 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 a concentrated urine, one with many solutes with a smaller amount of water.
Which of the following methods would be used to confirm the presence of Bence-Jones protein in the urine: - Urine protein electrophoresis or immunoelectrophoresis - Benedict qualitative test - Ictotest - Watson-Schwartz test
Urine protein electrophoresis or immunoelectrophoresis Either protein electrophoresis or immunoelectrophoresis can be used to confirm Bence-Jones proteinuria. Benedict test is used for detecting glycosuria. The Ictotest is used for detecting urine bilirubin. Watson-Schwarz test is used in the detection of porphobilinogen and urobilinogen.
Which of the following tests would be used in the assessment of glomerular filtration? - 24 hour urine protein - Creatinine clearance - PSP test - Urea
Creatinine clearance Creatinine excretion is related to muscle mass and is fairly constant from day to day for a given individual. Plasma concentrations of creatinine are used to assess renal function. Creatinine clearance is based on the serum creatinine level and is used to measure glomerular filtration rate, or GFR. Creatinine is filtered by the glomerulus and is not reabsorbed; therefore it can be used to estimate the GFR.
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-positive test result - False-negative test result - No adverse effect from the storage conditions - It can not be determined based on the information provided.
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.
Which test uses a vaginal fluid specimen to differentiate amniotic fluid from urine and other body fluids? - Optical density (OD) of bilirubin - Osmolality - Fern test - Amine (Whiff) test
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 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 volatilization of amines produced by anaerobic bacteria in bacterial vaginosis (BV).
An increased number of the cells seen in the image, upon microscopic examination of urine is termed: - Glycosuria - Hematuria - Uremia - Normal urine
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.
Identify the urine sediment element indicated by the arrow in the illustration: - Mucus thread - Cylindroid - Hyaline cast - Waxy cast
Hyaline cast Hyaline casts generally appear as 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 with and very refractive. They resemble short broad casts with broken ends and cracked edges.
With the development of fetal lung maturity, which of the following phospholipid concentrations in amniotic fluid increases? - Sphingomyelin - Phosphatidyl ethanolamine - Phosphatidylinositol - Lecithin
Lecithin When testing for fetal lung maturity, often the L/S ratio is determined. The L in the L/S ratio stands for Lecithin, which is one of the pulmonary surfactants needed to reduce the surface tension of the air-liquid interface of the alveolar lining, so that alveoli don't collapse upon expiration. The S stands for sphingomyelin, another pulmonary surfactant. Until about 32-33 weeks of gestation, the concentration of these two substances are quite similar; thereafter the concentration of lecithin increases significantly compared with the relatively constant concentration of sphingomyelin. In the absence of complications, the ratio of these two components reaches 2.0 at about 35 weeks gestation. Infants delivered after attaining an L/S ratio of 2.0 or higher rarely develop respiratory distress syndrome (RDS). This value of 2.0 has become the commonly accepted standard value indicating maturity in the fetus of a non-diabetic woman.
Which of the following conditions is most likely when an oligoclonal band is seen in CSF electrophoresis without a corresponding serum peak? - Lymphoproliferative disorder - Viral meningitis - Multiple sclerosis - Traumatic lumbar puncture
Multiple sclerosis Oligoclonal bands are found in the gamma region of CSF electrophoresis of most patients with multiple sclerosis. These bands are not seen in the serum electrophoresis of the same patients and are caused by increased levels of IgG in the CSF. Other conditions that may show oligoclonal bands in CSF electrophoresis include, inflammatory conditions, Guillain-Barre syndrome, bacterial meningitis, viral encephalitis, neurosyphilis, and subacute sclerosing panencephalitis.
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? - Lymphocytes - Mesothelial cells - Macrophages - Bronchial lining cells
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 indicate 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.
The microscopic finding illustrated in this image is a _____? - Hyaline cast - Fiber artifact - Cystine crystal - Granular cast
Fiber artifact This is a fiber artifact. Fiber artifacts can contaminate a urine specimen from clothing and diapers and 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. Hyaline casts generally appear as 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. 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. Granular casts are composed of plasma protein aggregates and cellular remnants in disease states. They appear to be from the lysosomes excreted by renal tubular cells in normal metabolism in nonpathologic conditions. Granular casts appear as cylinders of coarse, or fine granules in cast matrix.
Nitrates in urine are reduced to nitrites by: - Gram-positive bacteria - Acid fast bacteria - Gram-negative bacteria - Yeasts
Gram-negative bacteria Nitrates in urine are reduce to nitrites by gram-negative bacteria. It is important to mention that prolonged urinary retention in the bladder (at least 4 - 8 hours) is necessary in order to obtain an accurate result. Gram positive bacteria, yeast, and acid fast bacteria do not possess the enzyme reductase which aids in the reduction of nitrates to nitrites.
A 56-year old female was taken to the emergency room in a coma by her employer's nurse. She had lost 35 pounds in 3 months; she was always thirsty; drinking a lot of water and running to the bathroom. The following are her laboratory results: Results: (indicates reference range) pH: 7.11 (7.35-7.45) pCO2: 21 mm Hg (35-45 mm Hg) Glucose: 950 mg/dL (60-110 mg/dL) Serum osmolality: 365 mOsm/Kg (275-295 mOsm/Kg) Urine ketone: strongly positive (negative) Urine glucose: strongly positive (negative) What is the MOST likely cause of this patient's symptoms? - Gestational diabetes - Diabetes insipidus - Insulin dependent diabetes mellitus - Type II diabetes mellitus
Insulin dependent diabetes mellitus Insulin dependent diabetes mellitus is associated with a lack of insulin, which leads to increased blood and urine glucose. The classical symptoms of polyuria (frequent urination), polydipsia (increased thirst), polyphagia (increased hunger), and weight loss. Since this patient had not been diagnosed and appears to be poorly controlled, she developed hyperosmotic non-ketotic coma (HONK) which lead to her acidosis and elevated osmolality. The ketones and glucose in the urine indicate that the body is not able to use the glucose present, since there is a lack of insulin, and that the body is using fat for its source of energy instead. Gestational diabetes occurs in pregnant women and would not cause the laboratory results shown here. In addition, it would be very unlikely that a 56-year-old would be pregnant, so gestational diabetes is not suspected. Diabetes insipidus is a condition where the body is unable to reabsorb water in the kidneys. This type of diabetes is associated with an increased thirst and cravings for ice, along with very high volumes of diluted urine. However, diabetes insipidus can be ruled out due to the presence of glucose in the urine. Diabetes insipidus patients usually do not exhibit positive urine glucose results. Type II diabetes mellitus is usually not associated with ketonuria or ketoacidosis. Therefore, the best choice in this case is insulin dependent diabetes mellitus.
The indicator(s) used in the pH test region of the chemical reagent strips for urine is/are: - Methyl red and bromthymol red - Methyl blue and bromthymol blue - Methyl red and bromthymol blue - Methyl blue and bromthymol red
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).
Identify the urine sediment elements shown by the arrow: - Cylindroids - Mucus threads - Hyaline casts - Budding yeast
Mucus threads Mucus thread appear as long, thin ribbon like threads 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. Hyaline casts generally appear as 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. 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 primary site of reabsorption of glomerular filtrate is the: - Loop of Henle - Proximal convoluted tubule - Distal convoluted tubule - Collecting duct
Proximal convoluted tubule The proximal convoluted tubule is the convoluted portion of the nephron that lies between the Bowman's capsule and the loop of Henle and is the primary site of reabsorption for glomerular filtrate. It functions especially in the reabsorption of glucose, amino acids, sodium and chloride ions via active transport and water and urea via passive transport from the glomerular filtrate. Loop of Henle is the U-shaped part of the renal tubule situated between the proximal and distal convoluted tubules. It consists of the thin descending limb (permeable to water) and the thick ascending limb (impermeable to water). Water, sodium, and urea are reabsorbed in the descending limb via passive transport, while chloride is reabsorbed in the thick ascending limb by active transport. The distal convoluted tubule is located between the loop of Henle and the collecting duct and is the site where the final concentration of urine begins. The hormone aldosterone controls the reabsorption of sodium in response to the body's need for sodium. The collecting duct is the part of the nephron where the final concentration of urine takes place and depends on the osmotic gradient in the medulla and the hormone vassopressin, formerly antidiuretic hormone (ADH).
Which of the following statements is true regarding the storage and handling of urinalysis chemical reagent strips? - Make sure all of the pads on the strip have the same color prior to using the strip. - Touching the reagent areas of the strip will not interfere with test results. - Remove only enough strips for immediate use. - The bottle of reagent strips can remain uncovered once it has been opened.
Remove only enough strips for immediate use. Out of the options listed, the correct answer is to remove only enough strips for immediate use. Each pad on the test strip is a different color. If they all look the same, compare the strip with the chart provided by the manufacturer and discard the strip if the colors do not match the chart. It is never recommended to touch any of the reagent pad areas, or to leave the reagent strip bottle uncovered, as both can lead to inaccurate results and faulty reagent strip analysis.
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? - Traumatic tap - Subarachnoid hemorrhage - Meningitis - WAHA
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 RBC's 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.
A semen sample for semen analysis should generally be received at the testing site within what period of time? - one hour - two hour - three hours - four hours
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.
The cell indicated by the arrow is a: - Transitional epithelial cell - Renal tubular epithelial cell - Squamous epithelial cell - Macrophage
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.
