Small intestinal diarrhoea

24 Small intestinal diarrhoea


Diarrhoea may be determined to be of small intestinal origin when there are large volumes of faeces produced without evidence of tenesmus or dyschezia and there is no bright red blood or mucus present on the stools. Weight loss may accompany diarrhoea of small intestinal origin.


Some of the differential diagnoses of small intestinal diarrhoea include:


• Dietary
• food poisoning

• adverse reaction to food (allergy or food intolerance)

• dietary indiscretion (e.g. raiding the rubbish bin)

• sudden change of diet

• Gastric
• dumping syndrome, where too much food is presented to the duodenum rapidly

• Small intestinal diseases
• infectious (viral infections, bacterial, e.g. Salmonella spp., Campylobacter spp., E. coli enterotoxins).

• parasites (e.g. Giardia, strongyloides, ascarids, hookworms)

• inflammatory bowel disease

• infiltrative neoplasia (e.g. lymphoma, mastocytosis)

• lymphangiectasia

• brush border enzyme defects

• antibiotic responsive diarrhoea (ARD) (or antibiotic responsive enteritis)

• partial obstruction (e.g. intussusception, neoplasia, foreign body)

• extraluminal obstruction

• ischaemic disease (infarction, torsions)

• haemorrhagic gastroenteritis

• Secondary systemic disorders
• pancreatitis

• exocrine pancreatic insufficiency (EPI)

• Liver disease, including biliary diseases and porto-systemic shunts, intrahepatic cholestasis or bile duct obstruction

• Kidney disease

• Hyperthyroidism in cats

• Hypoadrenocorticism

• Congestive heart failure

• Feline viruses (feline infectious peritonitus (FIP), feline leukaemia virus (FeLV))

• Miscellaneous causes
• toxaemia (e.g. pyometra, peritonitis)

• toxins and drugs (e.g. non-steroidal anti-inflammatory drugs, lead, organophosphates)

• APUDomas (e.g. gastrinoma)

• autoimmune disorders (e.g. systemic lupus erythematosus)


Further investigation of chronic small intestinal diarrhoea



Dietary trial


If there are no abnormalities detected during the physical examination and the animal is bright and eating well, feeding an exclusion diet with a novel protein source or a hydrolyzed protein source for 2 to 6 weeks may be tried prior to further testing. In cats with diarrhoea, many respond to a restricted novel protein diet within a week. If the restricted diet is successful in improving the clinical signs, ideally a challenge with the previous food or snacks should be tried to prove that dietary sensitivity is the cause of the diarrhoea. Many owners are understandably reluctant to try this challenge and a new diet may be designed using the trial food. The owners should understand that the animal may become sensitized to the new diet and again develop diarrhoea.



Minimum data base


For cases in which the patient is systemically unwell or has not responded to dietary therapy and an appropriate de-worming programme, a minimum data base of haematology, serum biochemistry including basal cortisol and urinalysis should be performed. In cats, serologic tests for FeLV, FIP and a total serum thyroxine concentration should be included. These tests evaluate the patient for systemic diseases such as kidney disease, hepatopathies, hypoadrenocorticism, hyperthyroidism and viral diseases. A low albumin may be present in hepatopathies or protein losing enteropathy or nephropathy. If low protein is combined with low serum cholesterol and lymphopenia, lymphangiectasia may be present. Eosinophilia may be present with eosinophilic gastroenteritis, parasitism and hypoadrenocorticism. The minimum data base also aids in assessing hydration status and electrolytes which will guide the clinician in the choice of fluid therapy.



Faecal tests


Further testing may include faecal analysis for parasites and enteropathogenic bacteria, e.g. Salmonella, Campylobacter and Yersinia. Diarrhoea due to Campylobacter is more common in younger animals and the bacteria can also be isolated from the faeces of healthy animals. Salmonella can also be present in the faeces of animals without clinical signs and should probably not be treated unless serious or systemic signs are present as treatment may prolong the carrier state.


Toxin producing Clostridium difficile may cause acute or chronic diarrhoea. Faecal cultures for C. difficile are of no value because it is found in faeces from healthy animals and the presence of it does not prove that it is producing a toxin. Diagnosis of enterotoxigenic clostridia is best supported by a positive enterotoxin assay.


A fresh saline smear may detect Giardia trophozoites, although zinc sulphate flotation which detects Giardia cysts is more accurate. If giardiasis is suspected but cannot be confirmed a therapeutic trial with fenbendazole may be indicated.



Faecal alpha-1-antiprotease


Faecal alpha-1-antiprotease has been measured in the USA as an indicator of gastrointestinal (GI) protein loss and is useful to determine that intestinal loss is the cause of hypoproteinaemia.

Related posts:

  1. Oesophageal stricture in a cat
  2. Vomiting
  3. Linear foreign body in a cat
  4. Pancreatitis in a cat

Stay updated, free articles. Join our Telegram channel
Tags:
Sep 22, 2016 | Posted by in SMALL ANIMAL | Comments Off on Small intestinal diarrhoea

Full access? Get Clinical Tree
Get Clinical Tree app for offline access