Chronic Diarrhea Flashcards
What are the main differences between the diarrhea due to small bowel disease vs large bowel disease?
Small bowel:
- large volume of feces
- normal or increased frequency of defecation
- flatulence, steatorrhea
- melena (tarry, black)
- weight loss
- vomiting may occur
Large bowel
- small volume of feces
- increased frequency of defecation
- mucous in the feces
- hematochezia (frank, red)
- tenesmus
- pain or urgency to defecate
What are the main differentials for chronic small bowel diarrhea in dogs?
Primary Gastrointestinal:
- IBD (food or steroid responsive or antibiotic responsive/dysbiosis)
-lymphangiectasia (primary or secondary)
-parasites (giardia, roundworms, hookworms)
-histoplasmosis
-dietary indiscretion
- neoplasia
Systemic (extra GI):
- Addison’s
- Exocrine pancreatic insufficiency
- hepatobiliary disease
- chronic renal failure
What is lymphangiectasia?
Lymphatic lacteals in the small intestine are present in the small intestine to help absorb fat from the diet
- with lymphangiectasia they do not empty correctly and become distended (can rupture and cause irritation of intestinal lining)
-also leads to lack of protein absorption and protein loss
-most common in yorkies (primary)
-can also be secondary to neoplasia (lymphoma), food allergies, steroid responsive IBD, etc
What would increase suspicion of histoplasmosis in a chronic small bowel diarrhea case?
Fever, skin lesions, ocular lesions, lung signs
If you are very worried about parasites in a small bowel diarrhea case, what steps should you take?
Should run 3 separate zinc sulfate tests or send out fecal for PCR
- it is also ok to empirically deworm
What are the normal protein findings with antibiotic responsive IBD?
Often do not become hypoproteinemic
What is the best test for ruling out Addison’s disease?
Basal cortisol
- needs to be 2 or lower to rule out addisons
How can you rule out EPI?
Run a TLI test
What is the only food on the market that is both hydrolyzed and low fat?
Purina HA
When should a diet trial not be opted for in small bowel diarrhea cases?
In patients with moderate to severe hypoalbuminemia
- they are at risk for severe effusions
- in these cases imaging should be performed + maybe biopsy
How can you diagnose lymphangiectasia?
Endoscopy
- can grossly see dilated lacteals
- should also take biopsies for histopath for confirmation (lymphoplasmacytic inflammation)
What are the breeds that are predisposed to Primary intestinal lymphangiectasia?
Soft coated wheaten terriers, norwegian lundehunds, yorkies, maltese, shar pei
What are the main consequences of PLE?
- Thromboembolic disease
- vitamin deficiencies and malnutrition (can become vitamin D deficient and subsequently hypocalcemic- check ionized)
- poor oncotic pressure leading to pleural effusion, pulmonary edema, abdominal effusion and limb edema
What are some options for pulmonary edema due to a PLE?
Plasma, human albumin
What is the treatment for primary intestinal lymphangiectasia?
Strict prescription low fat diet long term (royal canin GI low fat, Hills i/d low fat, Purina HA)
- if mild inflammation is present on histopath but primary lymphangiectasia is still suspected, anti-inflammatory prednisone may be considered if not readily responding to treatment
What is the treatment for secondary intestinal lymphangiectasia?
Treatment focuses on underlying cause (such as steroids for IBD)
- low fat diet is used concurrently
- may consider hypoallergenic low-fat diet if food allergies have not been ruled out
If a patient has lost a lot of weight from lymphangiectasia and is not gaining it back, what is an option to supplement calories/fat which is not absorbed through the lacteals?
Medium chain triglycerides
If you suspect lymphangiectasia but cannot get definitive diagnosis through biopsies, what should be your plan of action?
Start with low fat diet (ideally hypoallergenic as well) for 3 weeks
- if not or only partial response start on prednisone 1 mg/kg/day for potential inflammation associated with primary lymphangiectasia
- if no response to that increase to 2 mg/kg per day for potential steroid responsive IBD
What test can you run to rule out histoplasmosis?
Urine antigen test
What are the main differentials for large bowel diarrhea?
- Histiocytic/ulcerative colitis (most common in young boxers and frenchies)
- inflammatory bowel disease (food responsive, antibiotic responsive or steroid responsive)
- parasites (whipworm, giardia)
- fiber responsive
- histoplasmosis
- prototheca (more common in southeast)
-clostridium perfringes - neoplasia (adenocarcinoma)
- irritable bowel syndrome
*Much less likely to be due to a secondary disease
What is the treatment for histiocytic/ulcerative colitis?
Enrofloxacin as it is due to invasive Ecoli species
- will NOT respond to steroids
