Urinalysis

Question 1

Why don’t horses have clear urine

Answer 1

Normally cloudy due to mucoprotein produced by renal epithelial cells

Question 2

Unreliable dip stick values

Answer 2

-Urobilinogen
-Nitrate
-Leukocyte esterase
-USG

Question 3

Urine pH

Answer 3

Carnivores 6-7.5
Herbivores 7.5-8.5
Not an accurate indicator of acid/base balance

Question 4

Alkalinization of urine

Answer 4

Urease producing bacteria and can often see crystal formation

Question 5

Urine protein measurement

Answer 5

Best for albumin and somewhat hemoglobin and myoglobulin. Must interpret with USG

Question 6

False positives for urine protein

Answer 6

-Very alkaline urine
-Cleaning agents

Question 7

Urine glucose measurement

Answer 7

There should be no glucose in urine due to renal reabsorption

Question 8

False positive glucose readings

Answer 8

Cleaning agents

Question 9

False negatives for glucose readings

Answer 9

-Vit C
-Ketonuria
-Cold urine (must warm to room temp before analysis)

Question 10

Causes of glucosuria

Answer 10

Most common in hyperglycemia:
-DM
-Severe pancreatitis
-Hyperadrenocorticism
-Stress
-Iatrogenic

Question 11

Normoglycemic glucosuria

Answer 11

-Previous transient episode of hyperglycemia
-Renal tubular defect

Question 12

Ketonuria

Answer 12

Indicates systemic problem not a renal problem. Produced when negative energy balance. Starvation or lack of insulin

Question 13

Ketone measurement

Answer 13

Measures acetone and acetoacetate

Question 14

False ketone positives

Answer 14

Pigmented urine

Question 15

Heme measurement

Answer 15

Very sensitive. Positive for hematuria, hemoglobinuria, and myoglobinuria

Question 16

Hematuria

Answer 16

Spin the urine and supernatant is not red
RBCs in sediment
Plasma is clear

Question 17

Hemoglobinuria

Answer 17

Due to intravascular hemolysis
Red, clear supernatant
Few or no RBC in sediment
Red plasma (happens first)
Evidence of anemia on CBC

Question 18

Myoglobinuria

Answer 18

Due to muscle injury and necrosis
Red-brown supernatant
Few or no RBC in sediment
Plasma is normal color
Increased CK and AST

Question 19

Urine bilirubin measurement

Answer 19

Positive reaction indicates conjugated bilirubin (precede hyperbilirubinemia)
Common to be 1+ in concentrated urine in dogs

Question 20

False bilirubin results

Answer 20

Degrades with exposure to UV (keep in the dark)