Urine Casts

Question 1

What do casts give us a snapshot of?

Answer 1

The lumen of the renal tubules and can indicate damage

Question 2

What is the matrix of the cast called?

Answer 2

Tamm-Horsfall Mucoprotein

Question 3

What do casts look like?

Answer 3

Cylindrical
Same size as the lumen
ends are tapered, irregular, or round
May have inclusions

Question 4

Where are casts formed?

Answer 4

The distal convoluted tubule

Collecting ducts

Question 5

How are casts formed?

Answer 5

Secreted protein precipitates in acidic conditions and forms casts shaped like the tubules

Question 6

What does the type of cast depend on?

Answer 6

How quickly the filtrate moves through the tubules

Question 7

Slower filtrate=

Answer 7

Waxy casts

Bad

Question 8

Sort of slowly filtrate=

Answer 8

Hyaline casts

Question 9

What pH of urine do casts dissolve quickly in?

Answer 9

Alkaline urine

Question 10

What species do we see casts less often?

Answer 10

Herbivores

Question 11

What does seeing casts in 0-1/hpf often indicate?

Answer 11

Lesions

Question 12

Does the number of casts present indicate the severity of the disease?

Answer 12

No

Question 13

Which casts are clear, colorless, transparent, and do not have inclusions?

Answer 13

Hyaline casts

Question 14

What kind of cast indicates a mild form of renal irritation

Answer 14

Hyaline casts

Question 15

What kind of cast increases with fever, poor renal profusion, strenuous exercise, general anesthesia?

Answer 15

Hyaline casts

Question 16

How does general anesthesia cause Hylaine casts?

Answer 16

When the blood pressure drops there is a temporary period of poor renal profusion

Question 17

What kind of light is the best to look at Hyaline casts under a microscope?

Answer 17

Dim light

Question 18

What are Hyaline casts with remnants of cells?

Answer 18

Granular casts

Question 19

What are granular casts made up of?

Answer 19

Degenerated renal cells, RBCS, WBCs

Question 20

With what condition do you see increased granular casts

Answer 20

Acute nephritis

Question 21

What does the presence of granular casts indicate?

Answer 21

More severe renal damage than hyaline casts

Question 22

What are hyaline casts with renal epithelial cells incorporated?

Answer 22

Epithelial Casts

Question 23

What condition can you see epithelial casts?

Answer 23

Acute nephritis

Question 24

Are epithelial casts common?

Answer 24

No, they are rare

Question 25

What kind of casts are wider hyaline casts with a “dull” appearance

Answer 25

Waxy casts

Question 26

What are the characteristics of waxy casts?

Answer 26

Square ends
Bigger
Colorless to gray
Refractile

Question 27

What is considered the worst casts?

Answer 27

Waxy casts

Question 28

What do waxy casts indicate?

Answer 28

Chronic severe degeneration of the tubules

Slowly moving filtrate

Question 29

Which casts contain retractile bodies and are sometimes referred to as oval fat bodies

Answer 29

Fatty Casts

Question 30

Where are Fatty casts seen?

Answer 30

In cats with renal disease

rarely in dogs with diabetes mellitus

Question 31

What kind of casts have WBCs in the matrix?

Answer 31

Leukocyte casts

Question 32

What does the presence of leukocyte casts indicate?

Answer 32

Inflammation of the renal tubules

Question 33

What kind of casts have RBCs in the matrix?

Answer 33

Erythrocyte casts

Question 34

What causes the presence of Erythrocyte casts?

Answer 34

Renal bleeding due to trauma, bleeding disorders

Question 35

What are erythrocyte casts part of?

Answer 35

The inflammatory response

Question 36

What pH do casts form in?

Answer 36

Acidic urine

Question 37

How do you report casts to the veterinarian?

Answer 37

1+, 2+, 3+,4+ and type