Diarrhoea in the cat and dog Flashcards
Define haematoxhezia
Fresh blood in stool
Define diarrhoea
Increased frequency, volume or fluidity
Differentiate acute and chronic diarrhoea
ACUTE 3 weeks, could be intermittent signs, investigate
How do you distinguish SI/LI/mixed?
HISTORY!
SI - primary or secondary GI disease
LI - confined to colon
SI PROBLEMS: volume, weight loss, V (both), general condition
LI PROBLEMS: mucus, frequency, tenesmus, dyschezia
Define dyschezia
Difficult or painful defecation
Differential diagnoses - acute SI diarrhoea, NO systemic signs - 4
- Diet (fast animals to determine if this is cause but be careful with cats as they don’t tolerate this well!)
- Helminths
- Protozoa - giardia
- Iatrogenic - drugs
Differential diagnoses - acute SI diarrhoea, WITH systemic signs - 5
-BACTERIA- salmonella or campylobacter (FAECAL CULTURE)
- VIRAL - distemper and parvo (dogs), panleukopaenia (cats) (do a faecal antigen test)
TOXINS
-HAEMORRHAGIC GASTROENTERITIS (dogs; high PCV, dehydrated)
-ACUTE PANCREATITIS (test - ultrasound and pancreatic lipase)
Differential diagnoses - acute LI diarrhoea, NO systemic signs - 4
-Whipworms
-Clostridia
-Giardia
-Campylobacter
RUN FAECAL EXAM AND CULTURE
DDx - chronic SI diarrhoea, EXTRA-GIT - 2 (with examples of each) and GIT - 8
EXTRA-GIT:
- METABOLIC: hepatic disease (PSS), hyperthyroidism (cats), addison’s disease (dogs), renal insufficiency
- PANCREATIC: EPI or chronic pancreatitis
GIT:
- Giardia
- chronic partial obstruction
- lymphagiectasia
- neoplasia - lymphosarcoma
- food-responsive disease
- IBD (lympho-plasmacellular)
DDx - chronic LI diarrhoea, GIT signs
GIT:
- IBD (lympho-plasmacellular, ulcerative colitis in boxers)
- polyps
- food-responsive disease
- neoplasia - usually adenocarcinomas
- chronic partial obstruction
- Cats: Tritrichomonas foetus
6 investigations for CHRONIC diarrhoea (order important)
- Faecal exam (flotation, culture) - excludes parasites/bacteria
- Heamatology, biochemistry and urinalysis (UA) - excludes systemic disease
- if SI diarrhoea: TLI (for EPI), pancreatic lipase/PLI (for pancreatitis), cobalamin (low levels indicate disease of ileum)
- Abdominal ultrasound - where is lesion? obstruction?
- Empiric treatment with elimination diet - food responsive disease
- if no response, biopsy/endoscopy
Advantages - endoscopy
- multiple biopsies from stomach, prox SI, ileum and colon possible
- non-invasive (except GA)
- direct visualisation of mucosa
- gives diagnosis (majority of cases)
- Difficult to diagnose intestinal lymphoma or lymphagiectasia as you only take a partial thickness biopsy
Disadvantages of biopsies via exp. lap. 4
- Invasive - caution in sick animals/cats/animals with decreased albumin levels
- only 2-3 biopsies from stomach and SI, not for colonic biopsies!
- more expensive and painful
- 20% mortality vs 2% mortality with endoscopy
Main causes for CHRONIC SI Diarrhoea in dogs - 4
- Food-responsive disease
- AB-responsive diarrhoea
- IBD (lympho-plasmacellular enteritis/colitis)
- Neoplasia
Define food-responsive disease
Diarrhoea gets better when given elimination diet (protien that animal has never eaten before, in reality this is pretty difficult so in fact a hydrolysed diet is given when the proteins are already broken down into oligopeptides). Usually better within first 2 weeks. Keep on this for at least 6-8 weeks. Then the animal can often be switched back on to original diet without clinical signs.
Define ARD
Antibiotic Responsive Diarrhoea (formerly SIBO).
Most commonly seen in young GSDs
Chronic SI or mixed diarrhoea
Give metronidazole for 4 weeks. Usually relapse though despite an initial quick recovery.
How do you diagnose IBD? Frequency? What do you seen on histopathology? What is the mechanism of IBD?
- By clinical exclusion! Most common enteropathy in dogs.
- Histopathology –> lymphoplasmacellular (most common), eosinophilic (rare), ulcerative colitis (only LI, rare, Boxers)/
-MECHANISM: IBD involves a mutated PRR (enterocytes and/or DCs in GIT) that wrongly identify commensal bacteria as pathogenic bacteria. The immune response to the ‘pathogenic bacteria’ is augmented meaning there is a massive increase in Th17 cells leading to massive mucosal inflammation. The anti-inflammatory cytokines produced by Tregs are insufficient to counter/balance this.
List the therapies for chronic enteropathies/IBD in DOGS (in a sequential treatment protocol) - 3
- ) Elimination diet
- ) METRONIDAZOLE for 3-4 weeks
- ) If inadequate response: PREDNISOLONE for at least 10 days then taper dose (i.e. an immuno-suppressive drug). If this steroid doesn’t work or is poorly tolerated, then use AZATHIOPRINE or CYCLOSPORINE.
List the therapies for chronic enteropathies/IBD in CATS (in a sequential treatment protocol) - 4
- ) Elimination diet
- ) PREDNISOLONE (10-14d then slow taper)
- ) If no response - CHLORAMBUCIL
- ) COBALAMIN supplementation: most cats with SI diarrhoea have low cobalamin levels.Studies show if you don’t give this PN, other treatments won’t work.
Define protein losing enteropathy
Syndrome of intestinal diseases. Non-selective protein loss - albumin low, +/- globulins low (both indicative of loss through GIT).
Causes - protein losing enteropathy - 3
- IBD
- Lymphagiectasia
- Neoplasia (lymphoma)
Clinical signs - protein losing enteropathy - 5 What must you do quickly?
- Diarrhoea
- Vomiting, anorexia
- Weight loss
- Ascites, pleural effusion (due to low albumin/globulin –> oedema), peripheral oedema
- Usually albumin and globulin serum concentrations low
-Take biopsy early!
