SA Diarrhoea Flashcards
How is chronic diarrhoea defined?
lasting > 3weeks
If acute diarrhoea is present, what should next be defined? What is the usual treatment of acute diarrhoea? How does this differ from chronic?
- with/without systemic signs?
- SI/LI/Mixed?
- Usually can be treated symptomatically +/- fasting for dogs if without systemic signs
> chronic must be investigated/worked up
Define diarrhoea
^ freq/volume/fluidity
Define meleana. What is this indicative of?
Black tarry stools indicates digested blood -> upper GI bleeding (stomach or SI)
Define flatulence
Excessive gas
Define dyschezia
Difficult/painful defeacation
Define heamatochezia. What is this indicative of?
Fresh blood in the stool indicative of lower GI (colon) bleeding
Define tenesmus
Ineffectual but urgent straining
Does intermittent diarrhoea over a period > 3 weeks still count as chronic?
YES
How can SI/LI be differentiated?
> history [SI v. LI]
- volume +++ … +
- mucus - … +++
- frequency + … +++
- tenesmus - … +++
- dychezia - … +
- weight loss ++ … +
- vomiting + … +
- general condition + … -
How are SI and LI diarrhoea subsequently refined?
- SI could be 1* or 2*
- LI is almost certainly 1* colon
What are the DDx for acute SI diarrhoea with NO systemic involvement? How may these be treated/ruled out?
- dietary (fast dogs [not cats], try elimination or hyposensitive diet)
- helminths (worm)
- protozoa (giardia)
- Iatrogenic (drug induced - many drugs can cuase this!)
What are the clinical signs that would suggest systemic involvement with acute SI diarrhoea?
Depressed/flat CV affected (^HR) Dehydration ^ temperature > indicates infection
What are the DDx for acute SI diarrhoea with systemic signs?
- Bacterial infection (salmonella, campylobacter)
- Viral ([dogs] distemper, parvo [cats] panleukopenia)
- Toxins
- Heamorrhagic gastroenteritis (dogs only)
- Acute pancreatitis
How are bacterial GI infections diagnosed?
Feacal culture
How common are bacterial causes of diarrhoea?
Rare
How are viral GI infections diagnosed?
Feacal Ag test
How do dogs with haemorrhagic gastroeneteritis present? What is the Tx?
^PCV, dehydrated
- Fluid therapy fixes most cases!
Give 4 DDx for acute LI diarrhoea. How may these be diagnosed?
- Whipworms
- Clostridia
- Giardia
- Campylobacter
> faecal examination and culture
How is chronic diarrhoea initially refined?
Same as acute - SI/LI/mixed? Physical exam (though this is usually unremarkable) - weight loss/stinted growth possible
What are the broad DDx categories for chronic SI diarrhoea? Which should be ruled out first?
1* (GI) and 2* (extra GI) -rule out 2* first
Give 6 DDx for 2* chronic SI diarrhoea. What broad categories do these fall into?
> Metabolic - hepatic disease (PSS) - Hyperthyroidism (cats) - Addisons disease (dogs) - Renal sufficiency > Pancreatic - EPI - Chronic pancreatitis
How would metabolic causes of chronic SI diarrhoea be differentiated from GIT 1* casues?
Usually other symptoms accompanying them - ie.
- PSS: CNS signs
- Hyperthyroidism: Polyphagia
- Renal insufficiency: PUPD
Give 6 DDx for chronic small intestinal diarrhoea
- giardia infection (may initially be acute then -> chronic)
- chronic partial obstruction
- lymphangiectasia
- Neoplasia: Lymphosarcoma most common
- Food-responsive disease
- IBD (Lympho-plasmacellular infiltration most common)
Give 6 DDx for chronic LI diarrhoea - is this likely to be 1* or 2*
Almost always 1* (ie. colon pathology)
- IBD (lympho-plasmacellular or ulcerative collitis in Boxers)
- Polyps
- Food-responsive disease
- Neoplasia (adenocarcinoma most common)
- Chronic partial obstruction
- Cats: tritrichomonas foetus (causes abortion in cows, recently spread to cats)
Which pathogen has recently jumped species to cause chronic LI diarrhoea?
Tritrichmonas foetus - causes abortion in cattle, recently spread to cats
Outline 6 invenstigation techniques for chronic diarrhoea? What can each rule out?
- feacal exam (flotation, culture) - rules out parasites, bacterial infection [campylobacter, salmonella]
- heamatology, biochem, UA - rules out renal failure, hepatic disease
- If SI diarrhoea do serum tests: Trypsin like immunoreactivity TLI [EPI], Pancreatic lipase PLI [pancreatitis], cobalamin [ileal disease if cobalamin low (should be absorbed in ileum)]
- Abdo ultrasound - locate lesion, blockage?
- Treat with elimination/hyposensitive diet - food-responsive disease
- If no response: BIOPSY (endoscopy or full thickness)
What 2 ways may biopsies be taken?
- Endoscopy: Gastroscopy - Stomach, SI Colonoscopy - ileum, colon - Ex lap Stomach and SI only NOT colon
What are the advantages and disadvantages of endoscopic biopsy?
+ non invasive (excpet GA)
+ direct visualisation of mucosa
+ conclusive in majority of cases
- difficult for Dx intestinal lymphoma, lymphangiectasia as not full thickness biopsy
What are the advantages and disadvantages of ex lap biopsy?
- invasive (esp problematic in sick animals, v albumin -> ^ risk dehiscence)
- only take 2-3 biopsies from stomach and SI
- cannot be used in colon
- expensive and painful
- ^ mortality rates (20% v 2% for endoscopy)
Where should intestinal biopsies NOT be taken from?
Peyers patches - will show lyphocyte infiltration and look like IBD
What are the MAIN causes of chronic SI diarrhoea in the dog?
- food responsive disease
- antibiotic responsive diarrhoea
- IBD (lyphoplasmacellular enteritis or colitis)
- neoplasia
How can food-responsive disease be ruled out?
- elimination/hyposensitivity diet > should improve within 2 weeks > keep feeding 6-8 weeks > NO treats! > can be switched back onto normal diet
What does ARD stand for? What was it formerly known as?
ARD: antibiotic responsive diarrhoea
SIBO: (Small intestinal bacterial overgrowth) - studies done in vitro to give this name, studies in vivo disputed hence name change.
What breed disposition does ARD show?
young GSD
What are the clinical signs of ARD?
chronic SI / mixed diarrhoea
How is ARD treated?
Metronidazole 15mg/kg po BID for 4 weeks
BUT should try and avoid ABs as will usually relapse
Manage diet - hydrolysed protein (hyposensitivity) diet
How is IBD diagnosed?
> CLinical exclusion- it is the most common chronic enteropathy in dogs
Histopathology - lympho-plasmacellular most comon
- eosiniphilic rare
- ulcerative colitis (LI) in boxers, rare
How is ulcerative colitis treated?
Enrofloxacin
- fine to treat this using ABs (unlike ARD where you should try and avoid ABs)
What is the pathogenesis of IBD?
PRRs on dendritic cells in gut mutate to recognise commencals as pathogens -> inflammatory T17 response
What is the “sequential treatment protocol for therapy of chronic enteropathies/IBD in dogs?
- Elimination diet / hydrolysed protein diet
- metrodinazole 10-15mg/kg BID for 3-4 weeks
- Prednisolone 2.2mg/kg/d for at least 10d, taper dose to e.o.d
- Azathioprine or cyclosporine if steroids poorly tolerated/unsuccessful
What side effects may steroids have? In which species are these more severe?
Cushings like symtoms - PUPD, polyphagia etc.
- common in dogs, cats have less side effects
What is the therapy protocol for IBD in cats?
- Elimination diet
- Prednisolone 2mg/kg/day for 10-14 days, slow taper
- Chlorambucil
> Cobalamin supplementation necessary ALWAYS - v cobalamin in serum decreases efficacy of treatement
Why is metronidazole not given to cats@?
Bitter tasting and too difficult to give!
What is the definition of a protein losing enteropathy?
- SYNDROME of intestinal disease
- non-selective protein loss -> low albumin, +- low globulins in serum
What may cause protein losing enteropathies?
- IBD
- lymphangiectasia
- neoplasia (commonly lymphoma)
Which species most commonly develops protein losing enteropathy?
Dogs
What are the clinical signs (“picture”) associated with protein losing enteropathies?
- VD+
- anorexia
- weight loss
- ascites, pleural effusion, peripheral oedema
- serum total protein low
> biopsy early on in workup to distinguish!
