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WorksheetsAUBF MODULE 5 POST QUIZ
Total questions: 101
Worksheet time: 2hrs 35mins
To preserve the integrity of reagent strips, it is necessary that they are
humidified adequately
stored in a refrigerator.
stored in a tightly capped container.
protected from the dark.
Using quality control materials, one should check
reagent strip performance:
1. at least once daily.
2. when a new bottle of strips or tablets is opened.
3. when a new lot number of strips or tablets is placed into use.
4. once each shift by each laboratorian performing urinalysis testing.
1, 2, and 3 are correct
1 and 3 are correct.
4 is correct.
All are correct.
Which of the following is not checked by quality control materials?
The technical skills of the personnel performing the test
The integrity of the specimen, that is, that the specimen was collected and stored properly
The test protocol, that is, that the procedure was performed according to written guidelines
The functioning of the equipment used, for example, the refractometer and the reagent strip readers
Quality control materials used to assess the performance of reagent strips and tablet tests must
be purchased from a commercial manufacturer.
yield the same results regardless of the commercial brand used
contain chemical constituents at realistic and critical detection levels.
include constituents to assess the chemical and microscopic examinations.
Which of the following is not a source of erroneous results when reagent strips are used?
Testing a refrigerated urine specimen
Timing using a clock without a second hand
Allowing excess urine to remain on the reagent strip
Dipping the reagent strip briefly into the urine specimen.
Select the primary reason why tablet (e.g., Ictotest)
and chemical tests (e.g., sulfosalicylic acid precipitation test) generally are performed.
They confirm results suspected about the specimen
They are alternative testing methods for highly concentrated urines.
Their specificity differs from that of the reagent strip test.
They are more sensitive to the chemical constituents in urine.
In a patient with chronic renal disease, in whom the kidneys can no longer adjust urine concentration, the urine specific gravity would be
1.000
1.010
1.020.
1.030
Urine pH normally ranges from
4.0 to 9.0
4.5 to 7.0
4.5 to 8.0
5.0 to 6.0
Urine pH can be modified by all of the following except
diet
increased ingestion of water
ingestion of medications
urinary tract infections
The double-indicator system used by commercial reagent strips to determine urine pH uses which two indicator dyes?
Methyl orange and bromphenol blue
Methyl red and bromthymol blue
Phenol red and thymol blue
Phenolphthalein and litmus
All of the following can result in inaccurate urine pH measurements except
large amounts of protein present in the urine
double-dipping of the reagent strip into the specimen
maintaining the specimen at room temperature for 4 hours
allowing excess urine to remain on the reagent strip during the timing interval.
Which of the following aids in the differentiation of hemoglobinuria and hematuria?
Urine pH
Urine color
Leukocyte esterase test
Microscopic examination
Select the correct statement(s)
1. Myoglobin and hemoglobin are reabsorbed readily by renal tubular cells.
2. Hemosiderin, a soluble storage form of iron, is found in aqueous solutions.
3. When haptoglobin is saturated, free hemoglobin passes through the glomerular filtration barrier.
4. Hemosiderin is found in the urine during a hemolytic episode
1, 2, and 3 are correct
1 and 3 are correct
4 is correct
All are correct
Which statement about hemoglobin and myoglobin is true?
They are heme-containing proteins involved in
oxygen transport
Their presence is suspected when urine and serum appear red.
Their presence in serum is associated with high creatine kinase values
They precipitate out of solution when the urine is 80% saturated with ammonium sulfate
On the reagent strip test for blood, any heme moiety (e.g., hemoglobin, myoglobin) present in urine catalyzes
oxidation of the chromogen and hydrogen peroxide.
reduction of the chromogen in the presence of hydrogen peroxide
reduction of the pseudoperoxidase while the chromogen undergoes a color change.
oxidation of the chromogen while hydrogen peroxide is reduced.
Which of the following blood cells will not be
detected by the leukocyte esterase pad because it
lacks esterases?
Eosinophils
Lymphocytes
Monocytes
Neutrophils
Microscopic examination of a urine sediment revealed an average of 2 to 5 white blood cells per high-power field, whereas the leukocyte esterase test by reagent strip was negative. Which of the following statements best accounts for this discrepancy
The urine is contaminated with vaginal fluid
Many white blood cells are lysed, and their esterase has been inactivated
Ascorbic acid is interfering with the reaction on the reagent strip
The amount of esterase present is below the sensitivity of the reagent strip test.
Which of the following statements describes the chemical principle involved in the leukocyte esterase pad of commercial reagent strips?
Leukocyte esterase reacts with a diazonium salt on the reagent pad to form an azo dye
An ester and a diazonium salt combine to form an azo dye in the presence of leukocyte esterase.
An aromatic compound on the reagent pad combines with leukocyte esterase to form an azo dye
Leukocyte esterase hydrolyzes an ester on the reagent pad, then an azocoupling reaction results in the formation of an azo dye
Which of the following conditions most likely accounts for a negative nitrite result on the reagent strip despite the presence of large quantities of bacteria?
1. The bacteria present did not have enough time to convert nitrate to nitrite.
2. The bacteria present are not capable of converting nitrate to nitrite.
3. The patient is not ingesting adequate amounts of nitrate in the diet.
4. The urine is dilute and the level of nitrite present is below the sensitivity of the test
1, 2, and 3 are correct
1 and 3 are correct
4 is correct
All are correct
The chemical principle of the nitrite reagent pad is based on the
pseudoperoxidase activity of nitrite
diazotization of nitrite followed by an azocoupling reaction
azocoupling action of nitrite with a diazonium salt to form an azo dye
hydrolysis of an ester by nitrite combined with an azocoupling reaction.
Which of the following substances or actions can produce false-positive nitrite results?
Ascorbic acid
Vaginal contamination
Strong reducing agents
Improper specimen storage
Normally, daily urine protein excretion does not exceed
150 mg/day
500 mg/day
1.5 g/day
2.5 g/day
Which of the following proteins originates in the urinary tract?
Albumin
Bence Jones protein
β2-Microglobulin
Uromodulin
Which of the following statements about Bence Jones protein is correct?
The protein consists of κ and λ light chains.
The protein is often found in the urine of patients with multiple sclerosis.
The protein precipitates when urine is heated to 100° C and redissolves when cooled to 60° C
The protein can produce a positive reagent strip protein test and a negative sulfosalicylic acid (SSA) precipitation test.
A urine specimen is tested for protein by reagent strip and by the SSA test. The reagent strip result is negative, and the SSA result is 2+. Which of the following statements best explains this discrepancy?
A protein other than albumin is present in the urine
The reagent strip result is falsely negative because the urine has a pH of 8.0.
A large quantity of amorphous urates in the urine caused the false-positive SSA result.
The time interval for reading the reagent strip pad was exceeded, causing a false-negative
result
Which of the following statements best describes the chemical principle of the protein reagent strip test?
The protein reacts with an immunocomplex on the pad, which results in a color change
The protein causes a pH change on the reagent strip pad, which results in a color change
The protein accepts hydrogen ions from the indicator dye, which results in a color change
The protein causes protons to be released from a polyelectrolyte, which results in a color change
A urine specimen is tested for glucose by a reagent strip and by the Clinitest method. The reagent strip
result is 100 mg/dL, and the Clinitest result is 500 mg/dL. Which of the following statements would best account for this discrepancy?
The Clinitest tablets have expired or were stored improperly.
A large amount of ascorbic acid is present in the specimen
A strong oxidizing agent (e.g., bleach) is contaminating the specimen.
The reagent strip is exhibiting the pass-through phenomenon, which results in a falsely low value
Which of the following substances if present in the urine results in a negative Clinitest?
Fructose
Lactose
Galactose
Sucrose
The glucose reagent strip test is more sensitive and specific for glucose than the Clinitest method because it detects
other reducing substances and higher concentrations of glucose
no other substances and higher concentrations of glucose
other reducing substances and lower concentrations of glucose
no other substances and lower concentrations of glucose
Which of the following statements about glucose is false?
Glucose readily passes the glomerular filtration barrier?
Glucose is reabsorbed passively in the proximal tubule
Glucosuria occurs when plasma glucose levels exceed 160 to 180 mg/dL
High plasma glucose concentrations are associated with damage to the glomerular filtration barrier.
The pass-through phenomenon observed with the Clinitest method when large amounts of glucose are present in the urine is due to
“carmelization” of the sugar present
reduction of copper sulfate to green-brown cupric complexes.
depletion of the substrate, that is, not enough copper sulfate is present initially
reoxidation of the cuprous oxide formed to cupric oxide and other cupric complexes.
The glucose specificity of the double sequential enzyme reaction used on reagent strip tests is due to the use of
gluconic acid
glucose oxidase
hydrogen peroxide
peroxidase
Which of the following ketones is not detected by the reagent strip or tablet test?
Acetone
Acetoacetate
Acetone and acetoacetate
β-Hydroxybutyrate
Which of the following can cause false-positive ketone results?
A large amount of ascorbic acid in urine
Improper storage of the urine specimen
Drugs containing free sulfhydryl groups
A large amount of glucose (glucosuria)
Which of the following will not cause ketonemia and ketonuria?
An inability to use carbohydrates
Inadequate intake of carbohydrates
Increased metabolism of carbohydrates
Excessive loss of carbohydrates
The ketone reagent strip and tablet tests are based on the reactivity of ketones with
ferric chloride
ferric nitrate
nitroglycerin
nitroprusside
Which of the following statements about bilirubin is true?
Conjugated bilirubin is water insoluble.
Bilirubin is a degradation product of heme catabolism
Unconjugated bilirubin readily passes through the glomerular filtration barrier.
The liver conjugates bilirubin with albumin to form conjugated bilirubin
The bilirubin reagent strip and tablet tests are based on
Ehrlich’s aldehyde reaction
the oxidation of bilirubin to biliverdin
the reduction of bilirubin to azobilirubin
the coupling of bilirubin with a diazonium salt.
Which of the following are characteristic urine findings from a patient with hemolytic jaundice?
A positive test for bilirubin and an increased amount of urobilinogen
A positive test for bilirubin and a decreased amount of urobilinogen
A negative test for bilirubin and an increased amount of urobilinogen
A negative test for bilirubin and a decreased amount of urobilinogen
Which of the following results show characteristic urine findings from a patient with an obstruction of the bile duct?
A positive test for bilirubin and an increased amount of urobilinogen
A positive test for bilirubin and a decreased amount of urobilinogen
A negative test for bilirubin and an increased amount of urobilinogen
A negative test for bilirubin and a decreased amount of urobilinogen
Which of the following conditions can result in false-positive bilirubin results?
Elevated concentrations of nitrite
Improper storage of the specimen
Ingestion of ascorbic acid
Ingestion of certain medications
Urobilinogen is formed from the
conjugation of bilirubin in the liver
reduction of conjugated bilirubin in bile.
reduction of bilirubin by intestinal bacteria.
oxidation of urobilin by anaerobic intestinal bacteria
Which of the following statements about urobilinogen is true
Urobilinogen is not normally present in urine
Urobilinogen excretion usually is decreased following a meal.
Urobilinogen excretion is an indicator of renal function
Urobilinogen is labile and readily photo-oxidizes to urobilin
The classic Ehrlich’s reaction is based on the reaction of urobilinogen with
diazotized dichloroaniline
p-aminobenzoic acid
p-dichlorobenzene diazonium salt
p-dimethylaminobenzaldehyde
A Watson-Schwartz test is performed on a urine specimen. The following results are seen: chloroform tube—red color in the bottom layer; butanol tube: red color in the top layer. These results indicate the presence of
urobilinogen
porphobilinogen
urobilinogen and other Ehrlich’s reactive substances
porphobilinogen and other Ehrlich’s reactive substances
Which of the following best describes the mechanism of ascorbic acid interference?
Ascorbic acid inhibits oxidation of the chromogen.
Ascorbic acid inactivates a reactant, promoting color development.
Ascorbic acid removes a reactant from the intended reaction sequence
Ascorbic acid interacts with the reactants, producing a color that masks the results.
Which of the following reagent strip tests can be
affected by ascorbic acid, resulting in falsely low or
false-negative results?
1. Blood
2. Bilirubin
3. Glucose
4. Nitrite
1, 2, and 3 are correct
1 and 3 are correct.
4 is correct
All are correct
Leaving excess urine on the reagent strip after removing it from the specimen will
Cause run-over between reagent pads
Alter the color of the specimen
Cause reagents to leach from the pads
Not affect the chemical reactions
Failure to mix a specimen before inserting the reagent strip will primarily affect the:
Glucose reading
Blood reading
Leukocyte reading
Both B and C
Testing a refrigerated specimen that has not warmed to
room temperature will adversely affect:
Enzymatic reactions
Dye-binding reactions
The sodium nitroprusside reaction
Diazo reactions
he reagent strip reaction that requires the longest reaction time is the:
Bilirubin
pH
Leukocyte esterase
Glucose
Quality control of reagent strips is performed
Using positive and negative controls
When results are questionable
At least once every 24 hours
All of the above
All except B
All of the following are important to protect the integrity of reagent strips except
Removing the desiccant from the bottle
Storing in an opaque bottle
Storing at room temperature
Resealing the bottle after removing a strip
The principle of the reagent strip test for pH is the:
Protein error of indicators
Greiss reaction
Dissociation of a polyelectrolyte
Double indicator reaction
A urine specimen with a pH of 9.0
Indicates metabolic acidosis
Should be recollected
May contain calcium oxalate crystals
Is seen after drinking cranberry juice
In the laboratory, a primary consideration associated with pH is:
Identifying urinary crystals
Monitoring vegetarian diets
Determining specimen acceptability
Both A and C
The principle of the protein error of indicators reaction is that
Protein keeps the pH of the urine constant
Albumin accepts hydrogen ions from the indicator
The indicator accepts hydrogen ions from albumin
Albumin changes the pH of the urine
All of the following will cause false-positive protein reagent strip values except:
Microalbuminuria
Highly buffered alkaline urines
Delay in removing the reagent strip from the specimen
Contamination by quaternary ammonium compounds
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:
Positive for orthostatic proteinuria
Negative for orthostatic proteinuria
Positive for Bence Jones protein
Negative for clinical proteinuria
Testing for microalbuminuria is valuable for early detection of kidney disease and monitoring patients with:
Hypertension
Diabetes mellitus
Cardiovascular disease risk
All of the above
The primary chemical on the reagent strip in the Micral Test for microalbumin bin
Protein
Antihuman albumin antibody
Conjugated enzyme
Galactoside
The principle of the protein-high pad on the Multistix
Pro reagent strip is the
Diazo reaction
Enzymatic dye-binding reaction
Protein error of indicators
Microalbumin-Micral-Test
The principle of the protein-low reagent pad on the Multistix Pro is the
Binding of albumin to sulphonphthalein dye
Immunologic binding of albumin to antibody
Reverse protein error of indicators reaction
Enzymatic reaction between albumin and dye
The principle of the creatinine reagent pad on microalbumin reagent strips is the
Double indicator reaction
Diazo reaction
Pseudoperoxidase reaction
Reduction of a chromogen
The purpose of performing an albumin:creatinine ratio is to:
Estimate the glomerular filtration rate
Correct for hydration in random specimens
Avoid interference for alkaline urines
Correct for abnormally colored urines
A patient with a normal blood glucose and a positive urine glucose should be further checked for:
Diabetes mellitus
Renal disease
Gestational diabetes
Pancreatitis
The principle of the reagent strip tests for glucose is the:
Peroxidase activity of glucose
Glucose oxidase reaction
Double sequential enzyme reaction
Dye-binding of glucose and chromogen
All of the following may produce false-negative glucose
reactions except
Detergent contamination
Ascorbic acid
Unpreserved specimens
Low urine temperature
The primary reason for performing a Clinitest is to:
Check for high ascorbic acid levels
Confirm a positive reagent strip glucose
Check for newborn galactosuria
Confirm a negative glucose reading
The three intermediate products of fat metabolism include all of the following except
Acetoacetic acid
Ketoacetic acid
β -hydroxybutyric acid
Acetone
The most significant reagent strip test that is associated with a positive ketone result is:
Glucose
Protein
pH
Specific gravity
The primary reagent in the reagent strip test for ketones is
Glycine
Lactose
Sodium hydroxide
Sodium nitroprusside
Ketonuria may be caused by all of the following except:
Bacterial infections
Diabetic acidosis
Starvation
Vomiting
Urinalysis on a patient with severe back and abdominal pain is frequently performed to check for
Glucosuria
Proteinuria
Hematuria
Hemoglobinuria
Associated with transfusion reactions
Hemoglobinuria
Myoglobinuria
Clear red urine and pale yellow plasma
Hemoglobinuria
Myoglobinuria
Clear red urine and red plasma
Hemoglobinuria
Myoglobinuria
Associated with rhabdomyolysis
Hemoglobinuria
Myoglobinuria
The principle of the reagent strip test for blood is based on the:
Binding of heme and a chromogenic dye
Peroxidase activity of heme
Reaction of peroxide and chromogen
Diazo activity of heme
A speckled pattern on the blood pad of the reagent strip indicates:
Hematuria
Hemoglobinuria
Myoglobinuria
All of the above
The principle of the reagent strip test for bilirubin is the:
Diazo reaction
Ehrlich reaction
Greiss reaction
Peroxidase reaction
An elevated urine bilirubin with a normal urobilinogen is indicative of
Cirrhosis of the liver
Hemolytic disease
Hepatitis
Biliary obstruction
The primary cause of a false-negative bilirubin reaction is
Highly pigmented urine
Specimen contamination
Specimen exposure to light
Excess conjugated bilirubin
The purpose of the special mat supplied with the Ictotest tablets is that
Bilirubin remains on the surface of the mat
It contains the dye needed to produce color
It removes interfering substances.
Bilirubin is absorbed into the mat.
The reagent in the Multistix reaction for urobilinogen is:
A diazonium salt
Tetramethylbenzidine
p-Dimethylaminobenzaldehyde
Hoesch reagent
The primary problem with urobilinogen tests using Ehrlich reagent is:
Positive reactions with porphobilinogen
Lack of specificity
Positive reactions with Ehrlich’s reactive substances
All of the above
The reagent strip test for nitrite uses the
Greiss reaction
Ehrlich reaction
Peroxidase reaction
Pseudoperoxidase reaction
All of the following can cause a negative nitrite reading except:
Gram-positive bacteria
Gram-negative bacteria
Random urine specimens
Heavy bacterial infection
A positive nitrite test and a negative leukocyte esterase test is an indication of a
Dilute random specimen
Specimen with lysed leukocytes
Vaginal yeast infection
Specimen older than 2 hours
All of the following can be detected by the leukocyte
esterase reaction except
Neutrophils
Eosinophils
Lymphocytes
Basophil
pH ranging from 4 to 6 usually has the corresponding color of?
Blue to yellow
Red to yellow
Green to yellow
Yellow to blue
Major protein in the urine?
Tamm horsfall protein
Globulin
Albumin
Immunoglobulins
Normal value of protein per 24 hours.
110 mg
120 mg
150 mg
100 mg
Post renal protienuria involves all of the following except?
Microalbuminuria
Menstrual contamination.
Lower UTI
Injury/Trauma
(+) SSA & (-) Rgt Strip=_______________________________
Albumin
Globlulin
Tamm horsfall protein
Proteins other than albumin
It is the general test for glucose an other reducing sugar.
Benedicts test
Clinitest
Acetest
Icto test
Screening tests for urinary infection combine the leukocyte esterase test with the test
pH
Nitrite
Protein
Blood
The principle of the leukocyte esterase reagent strip test uses a:
Peroxidase reaction
Double indicator reaction
Diazo reaction
Dye-binding technique
The principle of the reagent strip test for specific gravity uses the dissociation constant of a(n):
Diazonium salt
Indicator dye
Polyelectrolyte
Enzyme substrate
Reagent strip–specific gravity readings are affected by
Glucose
Radiographic dye
Alkaline urine
All of the above
None of the above
It is used as a confirmatory test for questionable reagent strip result on ketones.
Benedicts test
Clinitest
Acetest
Icto test
