Acute & Chronic Diarrhea

Question 1

How is acute diarrhea classified? How does this affect the initial approach to treatment?

Answer 1

Infectious (parasitic, bacterial, viral)

Hemorrhagic gastroenteritis

Obstructive

Toxin/drug-induced

Dietary

Extraintestinal

Question 2

What causes acute parasitic diarrhea?

Answer 2

Helminths (ascarid, hookworms, whipworms)

Protozoa (coccidia, giardia, cryptosporidium, tritrichomonas)

Do a fecal!

Question 3

What are common causes of acute bacterial diarrhea?

Answer 3

Clostridium
E coli
Salmonella
Campylobacter

Question 4

How is clostridiosis diagnosed?

Answer 4

Diagnosis is difficult

Enterotoxin can be identified by an ELISA or PCR - most sensitive means of diagnosis

Clostridial spores (safety-pin shaped) on fecal cytology does not confirm or exclude diagnosis

Question 5

What are the main causes of acute viral diarrhea?

Answer 5

Parvovirus

Coronavirus

Question 6

What type of canine parvovirus causes pathogenic enteric disease and can affect both cats and dogs?

Answer 6

Type 2

Question 7

What is the pathogenesis of parvo?

Answer 7

Ingestion -> viral replication in oro-pharyngeal LN -> spreads to rapidly diving cells (GI crypt epithelium, bone marrow) -> necrosis of lymphoid cells and GI epithelial cells -> enteritis/diarrhea, leukopenia

Question 8

What breeds experience more severe signs of parvo?

Answer 8

Dobermans

Rottweilers

Question 9

What are the clinical signs of parvo?

Answer 9

Diarrhea (+/- blood)
Vomiting/regurgitation
Depression
Anorexia
Fever
Leukopenia
Dehydration

Question 10

How is parvo diagnosed?

Answer 10

EM of fresh feces

Histopath of intestine

Tissue immunofluorescence

MOST PRACTICAL: Fecal ELISA (SNAP test)

Question 11

How would you get a false positive or false negative on ELISA (SNAP test) for parvo?

Answer 11

False positives: recent vaccination

False negatives: Ab-Ag complexes, shedding low #s

Question 12

How is parvo treated?

Answer 12

Isolate

Replacement fluids + electrolyte supplementation (young patients have high requirements than adults)

Blood component therapy

Parenteral antibiotics (for leukopenia)

Antiemetics

Nutrition- liquid diet

Tamiflu? Omega interferon? Hyperimmune plasma?

Question 13

What is Canine Hemorrhagic Gastroenteritis (HGE)?

Answer 13

Unknown cause, may be related to clostridial disease

Sudden onset of vomiting and bloody diarrhea

Increased PCV (>60%) with normal TP

Question 14

How is Canine Hemorrhagic Gastroenteritis (HGE) treated?

Answer 14

Replacement fluids
Antiemetics
Initially NPO and feed 12-24 hrs after vomiting stops

Question 15

What are the 11 aspects needed in a history for a patient with chronic diarrhea?

Answer 15

Duration
Diet
Progression
Appetite
Weight loss
Appearance of the feces
Frequency of defecation
Presence of vomiting
Tenesmus 
The environment in which the animal is kept 
Animal's breed and character

Question 16

What factor will differentiate whether a patient should receive serum TLI test or intestinal biopsy in cases of chronic diarrhea?

Answer 16

Albumin

Hypoalbuminemia (PLE) -> get biopsy
Normal albumin -> TLI

Question 17

An animal that receives a fecal, diet trial, intestinal biopsy, TLI, SIBO, cobalamine testing, radiographs is probably being worked up for what disease?

Answer 17

Chronic small bowel diarrhea

Question 18

What methods are use to retrieve an intestinal biopsy?

Answer 18

Endoscopy: not full thickness biopsy)

Exploratory laparotomy: full thickness biopsy

Laparoscopy: “best of both worlds”- minimally invasive, can get full thickness biopsy, can biopsy other organs

Question 19

How do you differentiate between small and large bowel diarrhea?

Answer 19

Differentiation is usually made from the history and laboratory findings and confirmed by a variety of simple studies which can be carried out in virtually any practice

Small bowel- TLI, cobalamine, folate, antibiotic trials

Large bowel- trichuris, tritrichomonas, diet change, colonoscopy