Urinary

Question 1

what is acute renal failure?

Answer 1

abrupt and sustained decrease in GFR resulting in azotaemia and fluid/electrolyte disturbance

Question 2

is acute renal failure reversible?

Answer 2

yes, in the early stages

Question 3

what is the main cause of post-renal azotaemia in horses?

Answer 3

neonates with bladder rupture

Question 4

what pre-renal factors can lead to acute renal azotaemia?

Answer 4

hypovolaemia
volume redistribution (effusions…)
decreased cardiac output
altered vascular resistance (sepsis…)

Question 5

what is the main renal factor that causes acute renal failure?

Answer 5

acute tubular necrosis secondary to ischaemia or nephrotoxin exposure

Question 6

what are some possible nephrotoxins?

Answer 6

antibiotics - ahminoglycosides, tetracyclines…
endogenous - haemoglobin, myoglobin…
others - NSAIDs, heavy metals…

Question 7

what commonly exacerbates the effect of nephrotoxic drugs?

Answer 7

dehydration

Question 8

what should be monitored in horses being given potentially nephrotoxic drugs?

Answer 8

serum creatinine

Question 9

what is the most nephrotoxic aminoglycoside?

Answer 9

neomycin

Question 10

what part of the kidney are aminoglycosides toxic to?

Answer 10

proximal tubular epithelial cells (reabsorbed and accumulates in these which interferes with function)

Question 11

what can possible be done to reduce the nephrotoxicity of aminoglycosides before they are administered?

Answer 11

treat with calcium

Question 12

what causes NSAIDs to be nephrotoxic?

Answer 12

medullary crest and papillary necrosis
sloughing of tubular epithelial cells

Question 13

how can acute renal failure be differentiated from pre-renal azotaemia?

Answer 13

pre-renal azotaemia should be rapidly reversible with fluid therapy

Question 14

what electrolyte changes are seen with acute renal failure?

Answer 14

hyponatraemia
hypochloraemia
hypocalcaemia
hyperphosphataemia

Question 15

when is hyperkalaemia seen with acute renal failure?

Answer 15

if the horse is oliguric

Question 16

what should be done to treat acute renal failure?

Answer 16

IV fluids
stop nephrotoxic drugs

Question 17

what fluids should be given to horses with acute renal failure?

Answer 17

hartmanns (maintaining twice maintenance if polyuric)

Question 18

when is diuretic therapy needed for acute renal failure treatment?

Answer 18

if the animal is oliguric

Question 19

what diuretic therapy is given to horses with acute renal failure and oliguria?

Answer 19

furosemide and dopamine (synergistic)

Question 20

why is dopamine given as part of diuretic therapy for horses with acute renal failure and oliguria?

Answer 20

potent renal vasodilator acting specifically on arteriole receptors

Question 21

why is chronic renal failure rare in horses?

Answer 21

massive reserve capacity

Question 22

what are the clinical signs of chronic renal failure?

Answer 22

weight loss, lethargy, poor coat, PUPD
oral ulceration, gastroenteritis, halitosis
ventral oedema

Question 23

how is chronic renal disease diagnosed?

Answer 23

persistent isosthenuria with azotaemia and clinical signs

Question 24

how is chronic renal disease treated?

Answer 24

palliative
always need water/salt available
lower protein nutrition
decrease calcium if high in diet

Question 25

what is classed as polyuria?

Answer 25

> 50ml/kg/day

Question 26

what is classed as polydipsia?

Answer 26

> 100ml/kg/day

Question 27

what is dysuria?

Answer 27

abnormal urination - pollakiuria, stranguria, haematuria, pyuria

Question 28

what are some possible causes of PUPD?

Answer 28

renal failure
PPID
excessive salt consumption
diabetes
sepsis/endotoxaemia
iatrogenic

Question 29

why does PPID cause PUPD?

Answer 29

hyperadrenocorticism causes increased cortisol which is a vasopressin antagonist so decreases vasopressin production/release

Question 30

why does diabetes mellitus cause PUPD?

Answer 30

hyperglycaemia leads to glycosuria cause osmotic polyuria and hence polydipsia

Question 31

what is a water deprivation test used for?

Answer 31

distinguish between diabetes insidious and psychogenic polydipsia

Question 32

what are some contraindications for performing water deprivation tests?

Answer 32

if animal is azotaemic or dehydrated

Question 33

how is a water deprivation test carried out?

Answer 33

empty bladder and get baseline body weight
deprive water of water access
measure USG, body weight and urea periodically
if USG increases >1.025 within 24 hours then they have psychogenic polydipsia

Question 34

what are the 3 main causes f red/brown urine?

Answer 34

blood
haemoglobin
myoglobin

Question 35

if you spin red/brown urine and it separates what can be diagnosed?

Answer 35

haematuria

Question 36

if you spin red/brown urine and it doesn’t separate what can be diagnosed?

Answer 36

haemoglobinuria
myoglobinuria

Question 37

how can red/brown urine due to myoglobin and haemoglobin be differentiated?

Answer 37

myoglobin will have increased creatine kinase and AST on serum biochemistry

Question 38

what are some causes of rhabdomyolysis?

Answer 38

sporadic/recurrent exertional
polysaccharide storage myopathy
atypical myopathy
post-anaesthetic myositis

Question 39

what are some possible causes of haemolysis?

Answer 39

immune mediated haemolytic anaemia
neonatal isoerythrolysis
infectious - babes, EIA

Question 40

if haematuria occurs throughout urination where can it be localised to?

Answer 40

kidney, ureter or bladder

Question 41

if haematuria occurs at the start of urination where can ut be localised to?

Answer 41

distal urethra

Question 42

if haematuria occurs at the end of urination where can it be localised to?

Answer 42

proximal urethra and bladder neck