Large Animal UT Dz Flashcards
What is the leading cause of urinary obstruction in farm (and sometime horses) animals?
> urolithiasis
- esp small ruminants d/t dietary imbalance (small holdings, pets)
- only males show obstruction signs
Pdf for urolithiasis
> castrated males
- development of urethra testosterone dependent
diet
- high conc/low roughage
- high phosphate/low calcium [phosphate recycled in saliva into GIT, saliva dependent on roughage chewing]
- high magnesium [struvite]
- alkaline urine [some types of crystals]
dehydration
UTI
Outline types of uroliths
> calcium (apatite and carbonate) - smooth round egg shaped > phosphate (calcium phosphate and mg ammonium phosphate) - = struvite - grit like > oxalate - spiky - can cause haematuria > silicate
Where is a common site of obstruction in small ruminants?
- urethral (vermiform) process in small ruminants and sigmoid
- distal sigmoid flexure in cattle (no vermiform process)
Clinical signs of urolithiasis
> early (blockage) - hameaturia, dysuria, cystals on prepuce - urine dribbling - tail flagging, colic signs > later 2-3d (azotemia) - anorexia, depression - preputial swelling (urethral rupture) - abdominal distension (bladder rupture) - recumbent, seziures, death
How can urolithiasis be dx?
- hx and clinical signs
- azotaemia, hyperkalaemia, hyponatraemia, acidosis
- ultrasonography (ibnly simple probe needed)
- radiography
Give 3 complications of urolithiasis
> bladder upture - painful becoming comfortable (~1 day) then sick d/t azotameia - abdo distenion and uroperitoneum > urethral rupture - swollen prepuce > hydronephrosis - chronic obstruction - dx via ultrasonogrpahy
Medical management of urolithiasis. Is this useful for obstructed animals?
> medical management
- increase diet Ca:P ratio
- urinary acidifciation (ammonium chloride, not very palatable)
Surgical managmeent of urolithiasis. Is this useful for obstructed animals?
> salvage prcedures, most appropriate for finshing animals for slaughter but not long term
- urethral process amputation
- perineal urethrostomy (infection risk, looks gross)
- tube cystotomy (more suitable for pets, allow urethral spasm to stop, let stones pass - leave for 1-2weeks, problems with bladder necrosis and peritonitis)
Which animals commonly get amyloidosis?
> cattle
with chronic sepsis
- mastitis, metritis, pneumonia, pericarditis
Pathogenesis of amyloidosis. Clinical signs.
- inflam -> ^ SAA -> glomerulopathy
- loss of glomerular function -> PLN
- oedema, weight loss, chronic D+
- proteinuria, hypoalbumenaemia, azotaemia
- raised serum fibrinogen, SAA, globulins
Tx amyloidosis
NO TX
- tx underlying infectious/inflammatory causes on farm to protect others
- cull
Causes of enzootic haematuria
> cattle and sheep grazing bracken - requires chronic >12months exposure - multiple cases > ptaquiloside carcinogens -> bladder wall neoplasia - haemorrhagic cystitis - haematuria > anaemia > ddx: Haemaglobinuria (dipstick)
What is ulcerative posthitis? PDf?
> Pizzle rot
ulcerative bacterial infection of prepuce and vulva mucous membranes
- corynebacterium renale
- high protein diets predispose
Clinical signs ulcerative posthitits
- pain
- loss of condition
- decreased fertility and libido
Tx ulcerative posthitits
- penicillin
- NSAIDs
- reduce dietary protein
What is the most common renal disease in cattle? When is this commonly seen?
Pyelonephritis
- ascending (usually) infection
- post-parturition and post service/covering
- following metritis and urolithiasis
CS of pyelonephritis
> acute - pyrexia - anorexia - depression - colic - v milk yield - stranguria, polyuria, haematuria, pyuria > chronic (harder to spot, more in cattle than horse) - weight loss - colic - v mili yeild - diarrhoea - polyuria - anaemia - less obvious UTI signs - painful, distorted kidneys on rectal
WHich bacteria are commonly implicated in pyelonephritis?
> G-
- coliforms, proteus, klebsiella, enterobacter
G+
- A. pyogenes, rarely c. renale
Dx of pyelonephitis?
- clinical signs, rectal palaption
- pyuria, haematuria, proteinuria
- azotaemia
- urine culure?
Tx pyelonephritis
- long term (14-21d) BS ABx
- oxytetracycline BEST or penicillin/aminoglycosides
How does umbilical infection occour?
- localises following haematogenous spread from gut, other sites of sepsis or generalised septicaemia
- can act as a portal for infection but less common than you would imagine
- arteries and urachus most commonly infected (cf. vein)
Tx umbilical infection
- if serious needs surgery
Where are the veins and urachus?
Caudal
- arteries cranially
Which bacteria are likely to cause umbilical infections?
- VERY MIXED
- G- (E coli, actinobacullus equiuli, klebsiella spp, pseudomonas spp, bacillus spp.)
- G+ (staph aureus, strep, enterococcus
- anaerobes (clostrdiu, spp)
> likely mixed
Clinical signs of umbilical infection? Ddx?
> ddx hernia
- well
- not hot etc.
infection
- fever, mallaise, lethargy, off suck
- heat, pain, swelling, discharge from umbilicus
- localising signs not present in every case (esp with generalised septicaemia)
~ NB check other organ and joint involvement is sepsis suspected
How can umbilical infection be dx?
> ultrasound
- enlargement of veins and areriers (should be
Tx umbilical infection
> surgical resection
- prevents spread of infection to other sites
- generalised septicaemia not good candidates for anaesthesia, tx septicaemia first
BS Abx
- monitor response wiht ultrasonography, if not improving change abx or consider surgery
- ceftiofur (foals need 2x adult dose)
- TMPS (economical, oral, inactivated in pus, organisms may not be sensitive)
- aminoglycosides (care young animals nephrotoxic, need to use in conjunction with G+ cover)
- penicililns and B lactams
- cephalosporins (3rd/4th gen ceftiofur)
Tx umbilical hernia
- small
What is the difference between patent and persistnet urachus?
> patent - has been closed then opens - infection - prolonged recumbency > persistnat - open since birth - excessive torsion during parturition? - may need cautery or surgical resection
Do you commonly see renal failure in horses?
PRE-RENAL most common, 1* renal fialure very rare
- 2* to hypovlolaemia with surgical colics etc.
RENAL disease lcinical signs and clin path only seen with renal failure (70% nephrons lost)
Causes of 1* renal failure
> as smallies
- congenital
- interstitial nephritis
- glomerulitis
- pyelonephritis
- amyloidosis
- neoplaisa
Clinical signs with renal failure in horses
- depression, anorexia, weight loss
- PUPD
- oedema and D+ (protein losing nephrotpathy)
- pyrexia and colic (pyrexia)
- encephalopathy, mucosal ulceration and excessive toth tartar (azotaemia)
What is seen on urinalysis with renal fialure in horses?
- proteinuria
- casts
- WBCs and bacteria
- haematuria
- inability to concentrate (USG 1.008-1.014 isosthenuric)
- ^ urine GGT: creatinine ratio to correct for urine flow
(liver, bile tree and renal tubules)
Serum biochem findings with renal failure
- azotaemia
- hyperkalameia
- hyponatraemia (kidney excretes ca and absorbs Na)
- hypercalcaemia ***
- hypophosphataemia ***
- ** cf. small animals excretes ca, absorbs Ph
Tx renal failure
> acute - restore circulatin volume (0.9% NacL) - diuresis (mannitol and furosemide) > chronic - no specific tx - supportive only - ad lib salt and water - high quality diet (low protein)??
When does bladder rupture occour in foals?
- during/soon after parturition (inherant bladder wall weakness?)
- hx previous normal urination does NOT r/o ruptured bladder as cases can rupture later (2* to infection etc.)
Ddx bladder rupture?
Meconium impaction
- tenesmus
> caudal position of legs if foals urinating
Pdf bladder rupture detected soon after parturition? WHere does the tear occour?
- no sex pdf (previously thought colts)
- tear dorsal aspect bladder
clinical signs of bladder rupture
- normally present within first 2-3d of life
- dysuria
- progressive depression and abdo distension
- ventral and preputial oedema
> matabolic derangements - azotaemia
- hyperkalameia (-> dysrhythmias)
- hyponatraemia (loss of renal regulation, PD)
- metabolic acidosis (loss of renal reg, 3rd spacing -> hypovolaemia and poor perfusion)
- respiratory acidosis (d/t compression of diaphragm)
What can UTI pdf bladder to?
rupture
- later than spontaneous after foaling
-
Dx bladder rupture?
- peritoneal fluid (serum creatinine ratio >2:1)
- ultrasound free fluid
Management of bladder rupture?
- not emergency surgery
- manage medically first to stabilise
- IV fluids, peritoneal drainage (0.9%NaCL, HArtmanns)
- Dextrose and insulin to promote intracellular movement of potassium (calcium or bicarb if not successful)
- drian abdo, peritoneal lavage
- intranasal oxygen
> good outcome majority of surgeries if stabilised first
