Urinalysis Practice Questions

MLS 4510 Urinalysis

What do hydrogen ions primarily combine with to maintain buffering capacity of blood?

Filtered bicarbonate ions

What are the primary substances removed from the blood by tubular secretion?

Protein-bound substances, hydrogen, potassium

The glomerular filtrate is best described as:

Protein-free ultrafiltrate of plasma

Production of antidiuretic hormone (ADH) is controlled by:

State of body hydration

Total renal blood flow is approximately:

1200 mL/min

Total renal plasma flow is approximately:

600 mL/min

Which of the following comes first?

Afferent arteriole

Where does aldosterone regulate sodium reabsorption?

Distal convoluted tubule

What is the primary ion affected by RAAS?

Sodium

Increased production of aldosterone causes:

Increased plasma sodium levels

What is the specific gravity of the glomerular ultrafiltrate?

1.010

Renin is produced by the kidney…

In response to low plasma sodium levels

Water is passively reabsorbed in all parts of the nephron except:

Ascending loop of Henle

The ideal urine sample volume is…

50 mL

What is defined as low urine output?

Oliguria

Which of the following is the ideal specimen when testing for a solute with diurnal variation?

24-hour specimen

The specific gravity of someone with diabetes mellitus is usually:

High

The specific gravity of someone with diabetes insipidus is usually:

Low

Urine is defined as:

An ultra-filtrate of plasma continuously formed by the kidneys

An unrefrigerated, unpreserved urine specimen should be tested within:

2 hours

The pseudoperoxidase reaction is the principle for the reagent strip test of:

Blood

Postrenal proteinuria may be caused by which of the following:

Prostatitis

Urine osmolality is affected only by which of the following?

Number of particles present

Which is the following compounds reacts with glucose to product the reagent strip result?

Glucose oxidase

Refractive index compares:

Light velocity in air with light velocity in solutions

The protein section of the reagent strip is most sensitive to:

Albumin

A student is having difficulty interpreting the reagent strip color reactions on a thick orange urine specimen. What is the probable cause?

Phenazopyridine

What reagent strip pad is most strongly associated with renal disease?

Protein

Urobilinogen is formed from:

Reduction of bilirubin by intestinal bacteria

Specimens that contain intact RBCs can be visually distinguished from specimens that contain just hemoglobin or myoglobin because:

Intact RBCs produce a cloudy specimen

A urine specimen with a pH of 9.0 indicates the patient should be:

Asked to collect a new specimen

A clinically significant cause of turbid specimens is:

Lipids

Which of the following will be detected by the reagent strip nitrite reaction?

E. coli

The chemical principle of the reagent strip test for bilirubin is that bilirubin:

Combines with a diazonium salt to form a colored complex

A urine specimen that tests positive for ketones and negative for glucose in most indicative of:

Starvation

A positive Clinitest with a yellow precipitate is noted from a patient with liver and cardiac abnormalities. What should the MLS do next?

Check the patient’s urine for color change

Increased turbidity in urine stored at room temperature is usually caused by:

Bacterial growth

Bacterial decomposition of urea produces urine that has an odor resembling:

Ammonia

Infection of the bladder is termed:

Cystitis

Which of the following crystals occurs in two very distinct forms?

Calcium oxalate

Clue cells are derived from:

Squamous epithelial cells

Under polarized light, all of the following will exhibit the Maltese cross formation except:

Pollen grains

Which of the following casts is not associated with severe urinary stasis?

Hyaline

Leukocytes that stain pale blue with Sternheimer-Malbin stain and exhibit brownian movement are:

Glitter cells

Lithotripsy is a procedure that is performed to:

Aid in the removal of renal calculi

Glomerular basement membrane thickening occurs in membranous glomerulonephritis as a result of deposition of:

IgG immune complexes

Calcium carbonate crystals can be distinguished from bacteria by:

Adding acetic acid

Oval fat bodies are:

Renal tubular epithelial cells that contain lipids

The presence of argentaffin cell tumors can be detected by the presence in the urine of:

5-HIAA

The finding of increased amounts of the serotonin degradation product 5-HIAA in the urine indicates:

Argentaffin cell tumors

The acid-albumin CTAB test is used to test for:

Mucopolysaccharides

In a fully automated analyzer, clarity is measured by:

Light scatter

The urinary sediment constituent most closely associated with bleeding within the nephron is the:

RBC cast

The silver nitroprusside test detects the presence of:

Homocysteine

What part of the kidney is uromodulin produced?

Proximal and distal convoluted tubules

What causes a patient with a vegetarian diet to have false-positive readings for blood on routine urine specimens?

Vegetable peroxidase

The pronounced edema associated with nephrotic syndrome is related to which of the following?

Hypoalbuminemia

Which of the following clearance substances does not require urine collection?

Cystatin C

What testing principle do semi-automated analyzers for the chemical urinalysis use?

Reflectance photometry

Which of the following results is unusual for a urine specimen from an uncontrolled diabetic?

High pH

What do the following results suggest?

Color & clarity: Yellow, cloudy

1.020 SG and 8.0 pH

Negative for glucose, ketones, bilirubin, blood

Trace proteins

Positive leukocyte esterase and nitrite

Urinary tract infection

To provide an accurate measure of renal blood flow, a test substance should be:

Cleared on contact with functional renal tissues

Myoglobinuria may be caused by what condition?

“Crush” injuries

A patient with severe back pain and 15 to 20 RBCs/hpf in the urine sediment may have:

Renal calculi

Which of the following is not an organic acidemia?

5-HIAA

Which of the following is not a porphyrin?

Porphobilinogen

Positive copper reduction test and negative glucose oxidase reagent strip test is suggestive of what?

Carbohydrate metabolism disorder

The presence of porphobilinogen in the urine can be suspected when:

Acidic urine turns a port wine color after standing

Urine with the characteristic odor of "sweaty feet" and a positive ketone test indicates the presence of:

Isovaleric acid

A urinalysis and a dinitrophenylhydrazine (DNPH) test are performed on an infant who is failing to thrive. If the DNPH test is positive, what result in the urinalysis will also be positive?

Ketones

An employee reports a negative nitroso-napthol test on a suspected case of tyrosyluria. What action should be taken next?

Collection of a blood sample for MS/MS testing.

What is the appropriate screening test for PKU?

Ferric chloride

Indigo blue in the urine can be indicative of a defect in the metabolism of:

Tryptophan

To differentiate between cystinuria and homocystinuria, the urine should be tested with:

Silver nitroprusside

Which disorder has a positive antineutrophilic cytoplasmic antibody test and is associated with pulmonary hemoptysis and urinary hematuria?

Granulomatosis with polyangiitis (Wegener’s)

Which condition would a patient not present with when diagnosed with Lesch-Nyhan disease?

Cystinosis

To enhance the excretion of hydrogen ions, ammonia is produced by the cells of the:

Distal convoluted tubule

What crystal is described as having a “coffin lid” appearance?

Triple phosphate crystals

What crystal is described as having a “thorny apple” appearance?

Ammonium biurate

What crystal comes in two forms?

Calcium oxalate

What crystal is associated with ethylene glycol poisoning?

Calcium oxalate monohydrate

What will distinguish the calcium phosphate versus sulfonamide crystals?

Addition of acetic acid

Cysteine crystals must be confirmed with what?

Cyanide-nitroprusside test

Which of the following is not a form uric acid can be found in?

Needle

Which statement regarding renal function is true?

Glomeruli are far more permeable to water and salt than other capillaries.

Which statement regarding normal salt and H₂O handling by the nephron is correct?

The ascending limb of the tubule is highly permeable to salt but not water.

Which statement concerning renal tubular function is true?

In salt deprivation, the kidneys will conserve sodium at the expense of potassium.

Which urine color is correlated correctly with the pigment-producing substance?

Deep yellow with yellow foam & bilirubin

A brown or black pigment in urine can be caused by:

Melanin

Which of the following is least affected by standing or improperly stored urine?

Protein

Urine production of less than 400 mL/day is:

Oliguria

Which of the following contributes to SG, but not to osmolality?

Protein

Urine with an SG consistently between 1.002 and 1.003 indicates:

Diabetes insipidus

In which of the following conditions is the urine SG likely to be below 1.025?

Chronic renal failure

What is the principle of the colorimetric reagent strip determination of SG in urine?

Ionic strength and pK_a of a polyelectrolyte

Which statement regarding urine pH is true?

Contamination should be suspected if urine pH is less than 4.5.

In renal tubular acidosis, the pH of urine is:

Consistently alkaline

In which of the following conditions is glycosuria most likely?

Pregnancy

Which of the following results are discrepant?

Negative blood but 6–10 RBCs/HPF