Pathology of the Urinary System II

Question 1

What causes Hypoxic/ Ischaemic injury?

Answer 1

Hypotension and/or ischaemia (heat stroke, dehydration)
* causes prolonged renal ischemia
* massive haemolysis- haemoglobinuric ATN
Necrosis of tubular epithelium and basement membrane

Question 2

What is nephrotoxic injury?

Answer 2

• Nephrotoxins cause Direct damage to epithelial cells
• produces reactive metabolites in the tubular filtrates, which can cause renal tubular epithelial necrosis after reabsorption
• indirectly stimulate vasoconstriction of intertubular capillaries
• in absence of renal failure- reversible

Question 3

What is AminoGlycoside toxiciy?

Answer 3

• Toxins are concentrated in lysosomes
• it escapes lysosomes to accumulate in the cytoplasm
• alters mitochondrial function and inhibits protein synthesis
• phospholipids accumulate intracellularly

Question 4

What occurs when antifreeze/ oxalate nephrosis is absorbed?

Answer 4

• absorbed from the GIT
• A small percentage is oxidised by hepatic alcohol dehydrogenase to the toxic metabolites
• there is a direct interaction of the toxic metabolites on the tubular epithelium
• calcium-oxalate crystals precipitate in the tubular lumen, tubular epithelial cells and the interstitium
• tubular blockage -> degeneration and necrosis -> renal failure

Question 5

What does oxalate nephrosis look like?

Answer 5

• large numbers of crystals in tubules
• usually arranged in rosettes or sheaves within the renal tubules

Question 6

What is tubular ecstasia?

Answer 6

renal epithelial degeneration and necrosis with a preserved tubular basement membrane

Question 7

What occurs when lilies are ingested?

Answer 7

• Vomiting and lethargy 1-5 days post ingestion
• The toxic ingredient is unknown

Occurs in cats

little amount = highly toxic

Question 8

What occurs when grapes and raisins are ingested?

Answer 8

• Toxin is unknown
• Proximal tubular degeneration and necrosis
  *

Question 9

Name four toxins that cause haemoglobinaemia

Answer 9

1. Chronic copper toxicity in sheep
2. leptospirosis or babesiosis in cattle
3. red maple toxicity in horses
4. babesiosis or autoimmune haemolytic anaemia in dogs

Question 10

What does haemoglinuric nephrosis look like grossly?

Answer 10

• renal cortex diffusely red-brown to blue-black
• Contains haemoglobin casts- red-black stippling of the capsular surface and continue into the cortex as radially orientated, dark red streaks

Question 11

What is myoglobinuric nephrosis?

Answer 11

Acute and extensive muscle necrosis
* rhabdomylosis
* severe direct trauma to muscle

causes myoglobin release from the muscle
large concentrations of myoglobin in the glomerular filtrate can increase the tubular necrosis that occurs as a result of renal ischemia

Question 12

What is leptospirosis?

Answer 12

• Interstitial nephritis
• causes abortion and stillbirths in livestock
• septicaemia, hepatitis, nephritis and meningitis

Question 13

What does leptospirosis look like grossly?

Answer 13

• radiating pale streaks
• interstitial and subcapsular fibrosis
• jaundice

Question 14

What does Encephalitozoon cuniculi look like?

Answer 14

• Occurs in rabbits
• obligate intracellular microsporidian parasite
• spreads through urine
• brain and kidney are the most heavily affected
• macrophages are unable to clear infection

Question 15

What is ‘white-spotted kidney’?

Answer 15

• Common incidental lesion in young calves
• progresses to fibrosis when aged

Multifocal nonsuppurative interstitial
nephritis

Question 16

What is pyelitis?

Answer 16

inflammation of the renal pelvis

Question 17

What is pylenephritis?

Answer 17

Inflammation of the renal pelvis
* ascending infection

Question 18

What is renal gout?

Answer 18

Deposition of urate crystals or urates

Question 19

What species lacks the enzyme uricase?

Answer 19

humans, birds and reptiles

Question 20

What is renal adenoma?

Answer 20

Rare, most common in horses and cattle
▪ Usually small and incidental findings
▪ Benign, arise from tubular epithelium

Question 21

What is renal carcinoma?

Answer 21

• Most common primary renal tumours of dogs, cattle and horses

Question 22

What is Nephroblastoma/Wilms’ tumour?

Answer 22

The most common renal neoplasm of pigs
and chickens
* Young animals(<2 y)
* Large masses, can be multiple

Question 23

What animals are specifically prone to nephrotoxin ATN?

Answer 23

Foals

Question 24

What is oxalate nephrosis?

Answer 24

The deposition of calcium oxalate crystals in kidney tubules

Question 25

What species is leptospirosis most likely to cause intestinal nephritis in?

Answer 25

Dogs

Question 26

What are the clinical signs of Encephalitozoon cuniculi?

Answer 26

• Weight loss, failure to thrive, neurological

Question 27

What is the most common cause of white-spotted kidney?

Answer 27

• E.Coli
• Salmonella
• Brucella

Question 28

What is Feline Infectious Peritonitis?

Answer 28

a Mutated Feline Enteric Coronavirus

Question 29

What is Pyelitis?

Answer 29

Inflammation of the renal pelvis

Question 30

What is vesicoureteral reflux?

Answer 30

Bacteria contaminated urine flows backwards from the bladder into the ureters

Question 31

What is a renal adenoma?

Answer 31

Primary epithelial renal neoplasia
* usually a small and incidental finding

Question 32

In what species is a renal carcinoma the most common in?

Answer 32

It is the most common primary renal tumour of dogs, cattle and horses

Question 33

What is a nephroblastoma?

wilms tumor

Answer 33

Most common renal neoplasm of pigs and chickens