UA 2

Question 1

What accounts for false positives in Bilirubin UA?

Answer 1

pyridium

Question 2

What accounts for false negatives in Bilirubin UA?

Answer 2

nitrites, light, ascorbic acid (light breaks down bilirubin)

Question 3

How is urobilinogen derived?

Answer 3

Urobilinogen is derived from metabolism of conjugates bilirubin by intestinal flora

Question 4

When would you have a positive test for urobilinogen?

Answer 4

positive urobilinogen is when there is so much bilirubin being produced but not getting out, ex: fecal obstruction or so many RBC being lysed, conjugated into LI, acted on by bacteria then reabsorbed ex: hemolytic anemia

Question 5

What is a normal reference range for urobilinogen?

Answer 5

.2-1mg/dl

Question 6

what causes increased urobilinogen (slide 55)

Answer 6

intravascular hemolysis (hemolytic anemia) or intestinal obstruction

Question 7

What is most likely to result in a false negative urobilinogin UA dip?

Answer 7

antibiotics - (killing off bacteria in intestines). Urobilinogen is derived from metabolism of conjugated bilirubin by intestinal flora

Question 8

What us the normal finding for nitrites in a UA dip?

Answer 8

Negative

Question 9

What does a urine level increase of nitrites indicate?

Answer 9

UTI

Question 10

What is the mechanism for increased nitrites with UTI?

Answer 10

many gram negative bacteria produce the enzyme nitrate reductase which reduced urinary nitrates to nitrites
ex: ecoli

Question 11

What can give a false positive Nitrite UA

Answer 11

pyridium - pain

Question 12

What can give a false negative?

Answer 12

Ascorbic acid (vitamin C), a low nitrite diet

Question 13

What is a normal test result for UA dip leukocyte esterase

Answer 13

negative

Question 14

what is a leukocyte esterase UA?

Answer 14

a screen to detect WBC in the urine

Question 15

What is a positive leukocyte esterase indicative of?

Answer 15

indicate likelihood of urinary tract infection

Question 16

what are 2 non-urinary causes of pyuria?

Answer 16

appendicitis and pancreatitis

Question 17

What could result in false positives of leukocyte esterase?

Answer 17

vaginal secretions

Question 18

what could result in false negative leukocyte esterase?

Answer 18

glucose, protein, increase SG

Question 19

for microscopic exam, What is a quality of normal urine?

Answer 19

normal urine in sterile

Question 20

for microscopic exam, Why is most bacteria in Urine sample gram negative?

Answer 20

due to the proximity of the G.I. tract

Question 21

for microscopic exam, What could be a non-urinary tract source of bacteria in a urine sample?

Answer 21

contaminants from skin or genital tract

Question 22

on microscopic exam, what would yeast look like in a urine sample?

Answer 22

budding, branching, - sugar i.e. diabetics and immunocompromised

Question 23

on microscopic exam: what would squamous epithelial cells indicate?

Answer 23

contaminant from lower GU(big fried eggs, lower 1/3 of urethra due to contamination or inflammation)

Question 24

on microscopic exam; what would transitional epithelial cells indicate?

Answer 24

line the urinary tract from renal pelvis to the proximal 2/3 of the urethra

Question 25

on microscopic exam, what would renal epithelial cells indicate?

Answer 25

rare cells okay, slough off, larger numbers seen in tubular damage, renal disease, trauma

Question 26

On microscopic exam, what would RBC and WBC appear as?

Answer 26

RBC = pale or yellowish, no nucleus or granules

Question 27

When are renal tubular epithelial (RTE) cell casts found?

Answer 27

found following diseases that damage the tubular epithelium

Question 28

What are sources of tubular damage that could cause renal tubular epithelial cell casts?

Answer 28

ex: heavy metal poisoning, glomerulonephritis,

Question 29

What are granular casts?

Answer 29

degenerated cellular casts

Question 30

what are waxy/”broad” degenerated granular casts often termed?

Answer 30

“renal failure casts”

Question 31

What are fatty- casts

Answer 31

chronic renal disease