Chapter 11

Question 1

What are the biomarkers of GFR?

Answer 1

Urea, creatinine, SDMA, cystitis C

Question 2

What is cystatin?
Where is it produced?
How it it processed in the glomerulus/renal tubules?
What other condition can cause it to elevate?

Answer 2

Cysteine protease inhibitor
All nucleated cells
Freely filtered and partially reabsorbed
Hyperthyroidism

Question 3

How does GFR alter with body size?

Answer 3

Decreases with increased weight

Question 4

How is GFR directly estimated?
What markers are available, what are their advantages/disadvantages?

Answer 4

Plasma clearance - two compartment model
Clearance = Dose/AUC
Inulin - cleared by non-renal routes
Creatinine - availability of injection challenging
Iohexol - only measured by specialists labs

Question 5

How can urinary tract rupture be confirmed on peritoneal effusion?

Answer 5

Fluid crea 2x serum crea

Question 6

How is phosphorus normally processed in the kidneys? What affects this?

Answer 6

Reabsorbed in proximal tubule
Inhibited by PTH and FGF-23

Question 7

What stimulates FGF-23 secretion?
Where is it secreted?
What are its effects?

Answer 7

Increased phosphate
Osteoblasts and osteocytes
Inhibits 1-alpha hydroxylase reducing formation of 1,25-dihydroxyvitamin D
Increases renal PO4 excretion

Question 8

What is NAG?
Where does it originate?
When can it be utilised?

Answer 8

N-acetyl-beta-D-glucosamidase
Tubular lysosomes of proximal tubule
Elevation in urine with tubular injury. May be useful in monitoring animals given nephrotoxic medication

Question 9

What is GGT?
Where does it originate?
When can it be utilised?

Answer 9

Gamma-glutamyl transferase
Brush border of proximal tubule
Elevation in urine with tubular injury. May be useful in monitoring animals given nephrotoxic medication

Question 10

What is NGAL?

Answer 10

Neutrophil gelatinise-associated lipocalin
Expression increased with tubular injury
Can be measured in blood/urine
Currently dogs only

Question 11

What is cystitis C as marker of?

Answer 11

Blood - GFR
Urine - tubular injury (normally catabolised by proximal tubular cells)

Question 12

What breed is associated with familial Fanconi syndrome?

Answer 12

Basenji

Question 13

What are the causes of acquired Fanconi syndrome?

Answer 13

Jerky treats
Drugs - tetracycline (OOD), aminoglycoside, streptozocin, cisplatin
Copper-associated hepatopathy
Pyelonephritis
Hypoparathyroidism/vit D

Question 14

What are the blood gas changes seen in RTA?

Answer 14

Normal anion gap metabolic acidosis