Urinalysis

Question 1

Primary organic component. Product of protein and amino acid metabolism

Answer 1

Urea

Question 2

Product of creatine metabolism by muscles

Answer 2

Creatinine

Question 3

Product of nucleic acid breakdown in food and cells

Answer 3

Uric acid

Question 4

Primary inorganic component. Found in combination with sodium and with many inorganic substances

Answer 4

Chloride

Question 5

Primarily from salt, varies by intake

Answer 5

Sodium

Question 6

Combines with sodium to buffer the blood

Answer 6

Phosphate

Question 7

Regulates blood and tissue fluid acidity

Answer 7

Ammonium

Question 8

It determine if fluid is urine

Answer 8

Urea and creatinine

Question 9

Average daily urine output

Answer 9

1200mL to 1500mL

Question 10

Decrease in urine output

Answer 10

Oliguria

Question 11

Cessation of urine flow

Answer 11

Anuria

Question 12

Increase excretion of urine at night

Answer 12

Ncturia

Question 13

Increase in daily urine volume and is associated with diabetes mellitus and diabetes insipidus

Answer 13

Polyuria
>2.5L/day in adults
>2.5 to 3mL/hr in children

Question 14

A patient presenting with polyuria,nocturia, polydipsia and low specific gravity is exhibiting symptoms of:

Answer 14

Diabetes insipidus

Question 15

Why is it possible to estimate the concentration of a normal urine specimen by its color?

Answer 15

Urochrome is produced and excreted at a constant rate, so its concentration is affected by the amount of water present in the urine

Question 16

State a pathologic cause of yellow urine in foam and of white urine foam

Answer 16

Yellow foam: bilirubin

White foam: protein

Question 17

How does the presence of phenazopyridine affect routine urinalysis testing?

Answer 17

The thick yellow-orange pigment in phenazopyridine masks reagent strip color reactions

Question 18

What is the significance of a cloudy, red urine?

Answer 18

The urine contains increased RBC’s

Question 19

Why is there a difference in the color of the serum from person with hemoglobinuria and myoglobinuria?

Answer 19

Myoglobin is more rapidly cleared from the plasma than is hemoglobin

Question 20

Under what conditions will a port wine urine color be observed in a urine specimen?

Answer 20

Urine containing porphyrins that has been exposed to air.

Question 21

Why might a brown/black urine have a positive chemical test result for blood?

Answer 21

The specimen containing hemoglobin that has been oxidized to methemoglobin. This may be seen in old specimen or in fresh specimen as a result of glomerular bleeding.

Question 22

State the conditions required for urines containing melanin or homogentisic acid to appear brown/black

Answer 22

Oxidation of melanogen to melanin produces a black urine; homogentisic acid turns black in alkaline urine.

Question 23

Name a pathologic cause and a nonpathologic cause of blue/green urine

Answer 23

Urinary and intestinal tract infections may produce blue or green urine. Breath deodorizers (clorets), methocarbamol (robaxin), amitriptyline (elavil), and methylene blue may produce blue or green urine.

Question 24

Differentiate between the appearance of amorphous urates and urates in a refrigerated urine specimen. What chemical test is critical to the differentiation?

Answer 24

Amorphous phosphates produce a white precipitate and amorphous urates produce a pink precipitates; the precipitation is pH dependent

Question 25

In what circumstances might a sediment be slightly warmed prior to microscopic examination?

Answer 25

To dissolve amorphous urates

Question 26

How will collection of a urine specimen using the midstream clean catch method affect the urine clarity?

Answer 26

The specimen will contain fewer contaminating structures and clarity will better represent the actual urine.

Question 27

When should a microscopic examination be performed on a clear urine specimen?

Answer 27

When a chemical test for protein, RBC's, or WBC's or bacteria is positive

Question 28

For what part of the routine urinalysis does specimen clarity serve as a method of quality control?

Answer 28

Microscopic

Question 29

Define specific gravity

Answer 29

The density of a solution compared with the density of a similar volume of distilled water

Question 30

Can a cloudy urine specimen have a low specific gravity? Why or Why not?

Answer 30

Yes, because substances not dissolved in the urine do not contribute to the specific gravity

Question 31

How can specific gravity be used to determine the quality of a specimen for urinalysis?

Answer 31

Significant pathologic constituents may not be detected in a dilute specimen

Question 32

Why is specific gravity of less value than osmolarity in evaluating renal concentration ability?

Answer 32

Specific gravity is influenced by the size of the molecules, such as urea, glucose, and protein that are not significant in renal concentration.