Chemical Examination of Urine
Clinical Significance of Positive Reaction for Blood: Myoglobinuria
-Muscular trauma/crush syndromes -Prolonged coma -Convulsions -Muscle-wasting disease -Alcoholism/overdose -Drug abuse -Extensive exertion -Cholesterol-lowering statin medications
Clinical Significance of Positive Reaction for Blood: Hematuria
-Renal calculi -Glomerulonephritis -Pyelonephritis -Tumors -Trauma -Exposure to toxic chemicals -Anticoagulants -Strenuous exercise
Clinical Significance of Positive Reaction for Blood: Hemoglobinuria
-Transfusion reactions -Hemolytic anemias -Severe Burns -Infections/malaria -Strenuous exercise/ RBC trauma -Brown recluse spider bites
A patient with a 2+ protein reading in the afternoon is asked to submit a first morning specimen. The second specimen has a negative protein reading. This patient is: A) Positive for orthostatic proteinuria B) Negative for orthostatic proteinuria C) Positive for Bence Jones protein D) Negative for clinical proteinuria
A
All of the following are important to protect the integrity of reagent strips EXCEPT: A) Removing the dessicant from the bottle B) Storing in an opaque bottle C) Storing at room temperature D) Resealing the bottle after removing a strip
A
All of the following are true for the ImmunoDip test for microalbumin EXCEPT: A) Unbound antibody migrates farther than bound antibody B) Blue latex particles are coated with antihuman albumin antibody C) Bound antibody migrates further than unbound antibody D) It utilizes an immunochromatographic prinicple
A
All of the following will cause false-POSitive protein reagent strip values EXCEPT: A) Microalbuminuria B) Highly buffered alkaline urines C) Delay in removing the reagent strip from the specimen D) Contamination by quaternary ammonium compounds
A
Leaving excess urine on the reagent strip after removing it from the specimen will: A) Cause run-over between reagent pads B) Alter the color of the specimen C) Cause reagents to leach from the pads D) Not affect the chemical reactions
A
Reagent strip reactions for blood are based on the: A) peroxidase activity of hemoglobin B) oxidation of hemoglobin peroxidase C) reaction of hemoglobin with bromthymol blue D) reduction of a chromogen by hemoglobin
A
Testing a refrigerated specimen that has not warmed to room temperature will adversely affect: A) Enzymatic reactions B) Dye-binding reactions C) The sodium nitroprusside reaction D) Diazo reactions
A
The protein section of the reagent strip is most sensitive to: A) Albumin B) mucoprotein C) Bence Jones protein D) Globulin
A
The pseudoperoxidase reaction is the principle of the reagent strip test(s) for: A) Blood B) Nitrite C) Specific gravity D) Urobilinogen
A
Which of the following is not tested on the Multistix Pro reagent strip? A) Urobilinogen B) Specific gravity C) Creatinine D) Protein-high
A
The protein section of the urine reagent test strip is most sensitive to: A) Albumin B) mucoprotein C) Bence Jones protein D) globulin
A) Albumin Albumin is the most abundant plasma protein and it is relatively small. In nephropathy, albumin will be the most abundant protein in the urine. This test is done to look for nephropathy (i.e., kidney disease). [Strasinger 2014, p77]
A test pad of urine reagent strip is impregnated with only sodium nitroprusside. This pad will react with: A) acetoacetic (diacetic) acid B) leukocyte esterase C) Beta hydroxybutyric acid D) ferric chloride
A) acetoacetic (diacetic) acid You should recognize that sodium nitroprusside is a reagent for ketones. It reacts with acetoacetic acid, NOT beta hydroxybutyric acid. [Strasinger 2014, p 83]
A reagent test strip had impregnated with stabilized, diazotized 2,4-dichloroaniline will yield a positive reaction with: A) bilirubin B) hemoglobin C) ketones D) urobilinogen
A) bilirubin Student should memorize the chemical reactions for each of the dipstick biochemicals. Diazo reagent is used for bilirubin. [Strasinger 2014, p83]
The principle of the protein error of indicators reaction is that: A) Protein keeps the pH of the urine constant B) Albumin accepts hydrogen ions from the indicator C) The indicator accepts hydrogen ions from albumin D) Albumin changes the pH of the urine
B
Region test strip pads for ketones primarily measure: A) acetone B) acetoacetic acid C) cholesterol D) Beta hydroxybutyric acid
B) acetoacetic acid The nitroprusside/Ferricyanide reagent strip reaction reacts with acetoacetic acid. Glycine must be present for the reaction to include acetone. Beta hydroxybutyric acid is present in the largest amount, but does not react with Nitroferricyanide. [Strasinger 2014, p 83]
When using the sulfosalicylic acid test, false-positive protein results may occur in the presence of: A) ketones B) alkali C) glucose D) radiographic contrast media
D) radiographic contrast media Radiographic dye will precipitate in SSA. [Strasinger 2008, p60]
Which of the following can give a false negative urine protein reading? A) contamination with vaginal discharge B) heavy mucus C) presence of blood D) very dilute urine
D) very dilute urine a,b, and c may give false positive results. A false-negative can result from a dilute urine, so answer d is correct. [Strasinger 2014, p78]
Fill in the Blank: When conjugated bilirubin is excreted through the bile duct into the intestine, the intestinal bacteria convert the bilirubin into a combination of uribilinogen and _________________.
Stercobilinogen
Fill in the Blank: In addition to glucose, commonly found reducing sugars include galactose, fructose, pentose, and lactose, of which __________________ is the most clinically significant.
Galactose
What is the test? Reagents: Multistix: glucose oxidase, peroxidase, potassium iodide Chemstrip: Glucose oxidase, Peroxidase, Tetramethylbenzidine Sensitivity: Multistix: 75-125mg/dL Chemstrip: 40mg/dL Interference: False POSitive: Contamination by oxidizing agents and detergents False NEGative: -High levels of ascorbic acid -High levels of ketones -High Specific Gravity -Low temperatures -Improperly preserved specimens
Glucose Reagent Strip
What is the correct interpretation based on these findings? Urine Bilirubin NEGative Urine Urobilinogen +++ (3+)
Hemolytic disease
What are some causes of Alkaline Urine?
HypERventilation Vomiting Renal tubular acidosis Presence of urease-producing bacteria Vegetarian diet Old Specimens
Fill in the Blank: _____________, a heme-containing protein found in muscle tissue, not only reacts positively with the reagent test strip for blood, but also produces a clear red-brown urine
Myoglobin
Indicate the source of the following proteinurias as prerenal, renal, or postrenal: Prostatitis
Post-renal
Indicate the source of the following proteinurias as prerenal, renal, or postrenal: Vaginal inflammation
Postrenal
Indicate the source of the following proteinurias as prerenal, renal, or postrenal: Acute phase reactants
Prerenal
Indicate the source of the following proteinurias as prerenal, renal, or postrenal: Multiple myeloma
Prerenal
What is the test? Reagents: Multistix: Tetrabromophenol blue Chemstrip: 3',3",5',5"-tetrachlorophenol 3,4,5,6-tetrabromosulfophthalein Sensitivity: Multistix: 15-30mg/dL albumin Chemstrip: 6mg/dL albumin Interference: False POSitive: -Highly buffered interference alkaline urine -Pigmented specimens; phenazopyridine -Quaternary ammonium compounds (detergents) -Antiseptics, chlorhexidine -Loss of buffer from prolonged exposure of the strip to the specimen reagent -High Specific Gravity False NEGative: -Proteins other than albumin -Microalbuminuria -Blood
Protein Reagent Strip
Indicate the source of the following proteinurias as prerenal, renal, or postrenal: Microalbuminuria
Renal
Indicate the source of the following proteinurias as prerenal, renal, or postrenal: Orthostatic proteinuria
Renal
The primary chemical on the reagent strip in the Micral-Test for microalbumin binds to: A) Protein B) Antihuman albumin antibody C) Conjugated enzyme D) Galactoside
B
The principle of the protein-high pad on the Multistix Pro reagent strip is the: A) Diazo reaction B) Enzymatic dye-binding reaction C) Protein error of indicators D) Microalbumin-Micral-Test
C
The reagent strip reaction that requires the longest reaction time is the: A) Bilirubin B) pH C) Leukocyte esterase D) Glucose
C
The principle of the reagent to strip for microalbuminuria is: A) a diazo reaction B) the protein error of indicators C) an immuno-chemical reaction D) the release of hydrogen ions to an indicator
C) an immuno-chemical reaction The reagent test strip for microalbuminuria uses an immunochemical technique. As opposed to the conventional protein error of indicators principal used in routine reagent strips, the diet is highly sensitive and specific for albumin. [Strasinger 2014, p77]
Indicate the source of the following proteinurias as prerenal, renal, or postrenal: Pre-eclampsia
Renal
The reason that an albumin: creatinine ratio can be performed on a random specimen is: A) creatinine corrects for over or under body hydration B) a first morning specimen may be too concentrated C) albumin corrects for over or under body hydration D) the reaction is sensitive to any level albumin
A) creatinine corrects for over or under body hydration Including a reagent strip reaction for creatinine, along with the reaction of microalbuminuria, the amount of creatinine that is excreted at a constant rate can correct for the hydration or dehydration and the patient's urine. [Strasinger 2014, p 78]
To prepare the reagent used in confirmatory protein testing, a laboratorian would: A) dissolve 3 g sulfosalicylic acid in 100 mL of water B) dissolve 5 g trichloroacetic acid in 100 mL of water C) combine 3 mL of hydrochloric acid and 97 mL of water D) combine 5 mL of glacial acetic acid and 95 mL of water
A) dissolve 3 g sulfosalicylic acid in 100 mL of water 3% SSA is used to confirm positive protein tests. 3% implies 3 g in 100 mL. [Campbell 1997, p1 36]
Routine screening of urine samples for glycosuria has been performed primarily to detect: A) glucose B) galactose C) bilirubin D) ketones
A) glucose the two sugars in these distractor answers are glucose and galactose. Galactosuria is a relatively rare genetic condition. The glucose biochemical strip is specific for glucose and will not detect galactose. Glucose is found in diabetes mellitus as well as other diseases. [Strasinger 2014, p79]
Which of the following regions is used to react with ketones in the urine? A) sodium Nitroprusside B) acetoacetic acid C) acetone D) beta hydroxybutyric acid
A) sodium Nitroprusside The only reagent listed is in answer A. The other answers are forms of ketones. [Strasinger 2014, p83]
Patient was severe back pain as the following urinalysis results: Color = dark yellow clarity = hazy specific gravity = 1.030 pH = 6.0 protein = trace glucose = NEGative ketones = NEGative blood = small urobilinogen = 0.4mg/dL nitrite = NEGative Leukocyte esterase = NEGative Microscopic findings RBC/hpf = 10 - 20 squamous epithelial cells = moderate calcium oxalate crystals = moderate In addition to the presence of blood, what other reagent test strip result relates to the patient's symptoms and likely diagnosis with renal calculi? A) specific gravity B) pH C) protein D) urobilinogen
A) specific gravity The high specific gravity indicates the patient is in a dehydrated state that favors the formation of renal calculi, producing the back pain and presence of red blood cells resulting from irritation to the urinary tract caused by the calculi. [Strasinger 2014, p157]
Microscopic analysis of urine specimen chose a moderate amount of red blood cells in spite of the negative results for occult blood using a region strip. The laboratory and should determine if this patient has taken: A) vitamin C B) a diuretic C) high blood pressure medicine D) antibiotics
A) vitamin C Ascorbic acid inhibits reactions that use peroxidase. [Strasinger 2014, p85]
A two-year-old child had a positive urine ketone. This would most likely be caused by: A) vomiting B) anemia C) hypoglycemia D) biliary tract obstruction
A) vomiting Vomiting leads to dehydration and utilization of fat for energy. Fat metabolism produces ketones. [Strasinger 2014, p82]
A urine specimen is analyzed for glucose by a glucose oxidase reagent strip and a copper reduction test. IF the reagent strip results are POSitive and the copper reduction results are negative, which of the following interpretations is correct? A) Galactose only is present B) Glucose only is present C) Lactose only is present D) Ascorbic acid only is present
B
A urine specimen with a pH of 9.0: A) Indicates metabolic acidosis B) Should be recollected C) May contain calcium oxalate crystals D) Is seen after drinking cranberry juice
B
A patient's urinalysis revealed a positive bilirubin and a decreased urobilinogen level. These results are associated with: , gathers A) hemolytic disease B) biliary obstruction C) hepatic disease D) urinary tract infection
B) biliary obstruction Biliary obstruction it was the normal flow of conjugated bilirubin into the intestine, and it backs up into the blood. From there, it will be filtered into the urine. Urobilinogen is a product of bacterial reduction of bilirubin in the intestine. Some urobilinogen is reabsorbed into the bloodstream and will be filtered in the into the urine. In biliary obstruction, less bilirubin reaches the intestine, and less is converted into urobilinogen. [Strasinger 2014, p86]
A 35-year-old woman presents with the sudden onset of severe, colicky pain on the right side of her abdomen. She does not relate the pain to food, but says that she cannot find a pain-free position. Physical examination finds market tenderness over the right costovertebral angle, but rebound tenderness is not present. A pelvic examination is unremarkable. Microscopic examination of her urine reveals the presence of numerous red blood cells. The urine is negative for esterase and nitrite, and no bacteria are seen. Which of the following is the most likely cause of her signs and symptoms? A) bilirubin gallstones B) calcium oxalate kidney stones C) cholesterol gallstones D) magnesium ammonium phosphate kidney stones E) acute uric acid nephropathy
B) calcium oxalate kidney stones The combination of severe flank pain (renal colic) and hematuria is highly suggestive of urolithiasis. The formation of urinary stones relates to decreased urine volume and increased urine concentrations of certain substances. Most stones contain calcium (either calcium oxalate or calcium phosphate) and are seen in patients with hypercalcinurina (with or without hypercalcemia), such as with hyperparathyroidism or diffuse bone disease. Magnesium ammonium phosphate stones are formed in alkaline urine is the result of urease-producing (urea-splitting) bacteria such as Proteus. The ammonia released from the breakdown of urea combines with magnesium and phosphate. These stones are large and may fill the renal pelvis (staghorn or struvite calculi). Examination of the urine with a dipstick reveals an alkaline urine that is positive for esterase (from the leukocytes in the urine) and nitrite (since Proteus reduces nitrate). Uric acid stones may form in patients with hyperuricemia, such as patients with Gallup for patients being treated for leukemias or lymphomas. Precipitation of uric acid within the tubules of the kidney could produce urinary obstruction and acute renal failure. This condition is referred to as acute uric acid nephropathy. In contrast to the signs and symptoms produced by kidney stones, gallstones may be asymptomatic, or they may produce fever, jaundice, and right upper abdominal pain (Charcot triad), due to acute inflammation of the gallbladder. Gallstones are either composed of cholesterol, bilirubin, or a combination of both. (Kumar, pp962-963. Rubin, pp 737-738)
Excess urine on the reagent test strip can turn a normal pH result into a falsely acidic pH when which of the following reagents runs into the pH pad? A) tetrabromophenol blue B) citrate buffer C) glucose oxidase D) alkaline copper sulfate
B) citrate buffer The protein bad the biochemical strip is held at an acid pH by citrate buffer. If this trip is not blotted, the acid buffer can "run over" to the pH pad and cause a falsely acidic pH. Tetrabromophenol blue is a pH indicator, not an acid. Glucose oxidase is the reagent on the glucose strip. Copper sulfate is the reagent of the reducing substances (Benedict) test. [Strasinger 2014, p 77]
Which of the following is the primary reagent in the copper reduction tablet? A) sodium carbonate B) copper sulfate C) glucose oxidase D) polymerized diazonium salt
B) copper sulfate The Clinitest™ is a copper reduction test, utilizing copper sulfate is the reactant. In the presence of a reducing substance, such as sugar, and heat and alkali, the copper is reduced, producing a change in color from blue to orange/red. [Strasinger 2014, p 81]
The reason for performing a Clinitest™ on a newborn's urine is to check for: A) fructose B) galactose C) glucose D) lactose
B) galactose galactosuria is an inborn error of metabolism, resulting in the failure to inherit the one of the end of enzymes needed to metabolize dietary galactose to glucose. Byproducts of this metabolic failure are toxic, and can result in severe mental retardation. Early detection and dietary changes can prevent the toxicity. [Strasinger 2014, p82]
A reagent test strip pad for blood has been reported positive. Microscopic examination fails to yield red blood cells. This patient's condition can be called: A) hematuria B) hemoglobinuria C) oliguria D) hemosiderinuria
B) hemoglobinuria The reagent strip test for blood is positive for hemoglobin from lysed red blood cells, filtered hemoglobin from intravascular hemolysis, and myoglobin. With no RBCs present, the terminology is hemoglobinuria, indicating the presence of filtered hemoglobin. [Strasinger 2014, p 84]
Upon standing at room temperature, urine pH typically: A) decreases B) increases C) remains the same D) changes depending on bacterial concentration
B) increases the change in pH is due to breakdown of urea to ammonia by urease producing bacteria, and loss of CO2. [Strasinger 2014, p31]
A 17-year-old girl decided to go on a starvation diet. After one week of starving yourself, what substance would most likely be found in her urine? A) protein B) ketones C) glucose D) blood
B) ketones Ketones are byproducts of fat metabolism. During low carbohydrate or starvation diets, ketones can be found in the urine. [Strasinger 2014, p82]
The principle of the region to strip her urine protein depends on: A) an enzyme reaction B) protein error of indicators C) copper reduction D) the toluidine reaction
B) protein error of indicators Two pH indicators are incorporated in the strip. Protein accepts H+ ions from the pad, resulting in a pH and, therefore, color change. [Strasinger 2014, p77]
A 59-year-old man is evaluated for back pain. Urine studies (urinalysis by multiple reagent strip) include: Specific gravity= 1.017 pH=6.5 protein= NEGative glucose= NEGative blood= NEGative Microscopic findings rare epithelial cells Urine protein electrophoresis monoclonal spike in gamma globulin region Which of the following statements best explains these results? A) urine protein is falsely negative due to the specific gravity B) urine protein is falsely negative because the method is not sensitive for Bence Jones protein C) microscopic examination is falsely negative due to the specific gravity D) electrophoresis is incorrect and should be repeated
B) urine protein is falsely negative because the method is not sensitive for Bence Jones protein Reagent strip tests for protein are primarily sensitive to albumin. The monoclonal spike in the gamma region indicates the presence of Bence Jones protein that is an immunoglobulin rather than albumin. [Strasinger 2014, p84]
Which of the following positive chemical reactions is most closely associated with the presence of yeast in the urine sediment? A) Nitrite B) protein C) glucose D) blood
C) glucose Yeast cells are commonly seen in urine specimens from persons with diabetes mellitus, because the high glucose content provides an excellent growth medium for yeast. [Strasinger 2014, p119]
eGFR calculated by the MDRD-IDMS traceable study equation takes into account the patient's age, race, gender, and serum concentration of which of the following ? A) urea B) ammonia C) creatinine D) cystatin C
C) creatinine Several methods have been described to estimate glomerular filtration. The creatinine clearance test uses plasma creatinine versus urine creatinine. However, it is unwieldy and time-consuming for the patient. The most commonly used estimated formula, called the modification of diet and renal disease-isotope-dilution-mass-spectrophotometry-traceable (MDRD-IDMS traceable) uses patient ethnicity, serum creatinine, age, and gender. [Strasinger 2014, p48]
What is the correct interpretation based on these findings? Urine Bilirubin +++ (3+) Urine Urobilinogen Normal
Bile Duct Obstruction
What is the test? Reagents: Multistix: 2,4-dichloroaniline diazonium salt Chemstrip: 2,6-dichlorobenzen-diazonium salt Sensitivity: Multistix: 0.4-0.8mg/dL Chemstrip: 0.5mg/dL Interference: False POSitive: -Highly pigmented urines, phenazopyridine -Indican (intestinal disorders) -Metabolites of Lodine False NEGative: -Specimen exposure to light -Ascorbic acid greater than 25mg/dL -High concentrations of nitrite
Bilirubin Reagent Strip
What is the test? Reagents: Multistix: Diisopropylbenzen dihydroperoxide and 3,3',5,5'-tetramethylbenzidine Chemstrip: dimethyldihydroperoxyhexane and tetramethylbenzidine Sensitivity: Multistix: 5-20 RBC/mL; 0.015-0.062 mg/dL hemoglobin Chemstrip: 5 RBC/mL, hemoglobin corresponding to 10 RBCs/mL Interference: False POSitive: Strong oxidizing agents Bacterial peroxidases Menstrual contamination False NEGative: -High Specific Gravity -Crenated cells -Formalin -Captopril -High concentrations of nitrite -Ascorbic acid greater than 25mg/dL -Unmixed specimens
Blood Reagent Strip
Following your analysis results were obtained from an 18-year-old woman in labor: pH = 6.5 protein = 30mg/dL glucose = 250mg/dL ketones = NEGative bilirubin = small (color slightly abnormal) blood = NEGative nitrite = NEGative urobilinogen = 0.1 EU/dL specific gravity = 1.025 copper reduction test = 1.0g/dL Which of the following is the most likely explanation for the patient's positive copper reduction test? A) only glucose is present B) only lactose is present C) glucose and possibly other reducing substances/sugars are present D) results are false positive due to the presence of protein
C) glucose and possibly other reducing substances/sugars are present Region strip glucose test using glucose oxidase is specific for glucose; therefore, glucose must be present in the sample. The copper reduction test has a lower sensitivity in the region strip; therefore, the higher reading on the copper reduction test indicates the presence of an additional sugar. In the case of a nursing mother, the most likely additional sugar is lactose. [Strasinger 2014, p81]
A urine specimen with an elevated urobilinogen and a negative bilirubin may indicate: A) obstruction of the biliary tract B) viral hepatitis C) hemolytic jaundice D) cirrhosis
C) hemolytic jaundice Each answer is a different liver/biliary condition. In hemolytic jaundice, the total bilirubin goes up, but the direct/conjugated bilirubin does not. [Strasinger 2014, p 86]
The creatinine clearance is reported in in: A) mg/dL B) mg/24hrs C) mL/min D) mL/24hrs
C) mL/min Creatinine clearance is a filtration rate, and is reported in minutes. The The sample is a 24 hour urine, which is entered into the calculation as the volume in milliliters, and the factor of 1440 minutes per 24 hours is applied. [Strasinger 2014 p 47]
A false-NEGative LE reaction may be caused by: A) the presence of eosinophils and basophils B) increased bacteria C) lysed leukocytes D) failure to wait 2 minutes to read the reaction
D
Failure to mix a specimen before inserting the reagent strip will primarily affect the: A) Glucose reading B) Blood reading C) Leukocyte reading D) Both B and C
D
In the laboratory, a primary consideration associated with pH is: A) Identifying urinary crystals B) Monitoring vegetarian diets C) Determining specimen acceptability D) Both A and C
D
Quality control of reagent strips is performed: A) Using positive and negative controls B) When results are questionable C) At least once every 24 hours D) All of the above
D
Testing for microalbuminuria is valuable for monitoring patients with: A) Hypertension B) Diabetes mellitus C) Cardiovascular disease risk D) All of the above
D
The principle of the reagent strip test for pH is the: A) Protein error of indicators B) Greiss reactions C) Dissociation of a polyelectrolyte D) Double indicator reaction
D
Urine test strip positive for blood may indicate all, EXCEPT: A) Hematuria B) Hemoglobinuria C) Myoglobinuria D) Meat diet
D) 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. A little Myoglobinuria can be caused by muscular trauma, prolonged coma, drug abuse etc
A woman in her ninth month of pregnancy has a negative urine glucose result with the new reagent to strip, but a positive reaction with the copper reduction method. The reducing substance most likely responsible for these results is: A) Maltose B) galactose C) glucose D) lactose
D) lactose The two keys here are that the dipstick glucose is negative, so the answer is not glucose; and that the woman is pregnant, and about to deliver. This implies that she may be making milk. Lactose is most likely answer. [Strasinger 2014, p81]
A clear, red-brown urine specimen resulted in a positive reaction for blood on the reagent test strip, but no RBCs were seen on microscopic examination. These results most likely indicate the presence of: A) pyridium B) ascorbic acid C) porphyrins D) myoglobin
D) myoglobin Myoglobin is a heme-containing muscle protein that reacts positively with the reagent to strip out for blood, but cannot be viewed microscopically. [Strasinger 2014, p87]
What is the test? Reagents: Sodium Nitroprusside Glycine (chemstrip) Sensitivity: Multistix: 5-19mg/dL acetoacetic acid Chemstrip: 9mg/dL acetoacetic acid; 70mg/dL acetone Interference: False POSitive: Phthalein dyes Highly pigmented red urine Levodopa Medications containt free sulfhydryl groups False NEGative: Improperly preserved specimens
KETONE Reagent Strip
What is the correct interpretation based on these findings? Urine Bilirubin + or - Urine Urobilinogen ++ (2+)
Liver Damage
A 24 hour urine from a man who had no evidence of kidney impairment was sent to the laboratory for hormone determination. The volume was 600 mL, but there was some question as to the completeness of the 24 hour collection. The next step would be to: A) perform the hormone determination, since 600 mL is a normal 24 hour urine volume B) check the creatinine level; if it is less than 1 g, to the procedure C) report the hormone determination in mg/dL in case the specimen is incomplete D) check the creatinine level; if it is greater than 1 g, do the procedure
The reader should know the approximate volume of a daily void, which is approximately 1500 mL, but can range from 600 to 2000 mL. In order to determine if 600 is the actual volume, or some sample was missed, evaluate the creatinine. Creatinine is excreted at approximately 1.2 g/24 hour Now evaluate the choices. a) could be correct, but it is not sufficient, since 600 mL is unusually low b) is incorrect, because the creatinine is too low. c) is incorrect, because it does not answer the medical question, and it bills the patient. This leaves d), which is the correct answer. [Mcbride 1999]
