Part 2: The scoop on poop: Investigating diarrhea in cats and dogs

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•ACUTE

• Dietary

• overeating, sudden diet change, spoiled food

• Infection / parasites

• Toxins

• Lead, OPs, plants

•CHRONIC

• Diet related

• dietary allergies, intolerance

• Infection/parasites

• Immune mediated / inflammatory

• eosinophilic, histiocytic, lymphocytic‐ plasmacytic enteritis

• Neoplastic

• lymphosarcoma, adenocarcinoma

• Secondary GI causes

• hyperthyroidism, EPI, uremia, hypoadrenocorticism

Not a complete list!Will be covered fully in future 

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Some causes of diarrhea in cats and dogs

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•Small intestinal (Small bowel)

• Dietary

• overeating, sudden diet change, spoiled food

• Infection / parasites

• Viral (eg parvovirus, coronavirus)

• Bacterial (eg salmonella, campylobacter)

• Parasites 

• Inflammatory

• Inflammatory bowel disease

• Neoplasia

• Eg alimentary lymphoma

• Extra‐GIT causes (secondary causes)

•Large intestinal (Large bowel)

• Diet related

• dietary allergies, intolerance

• Inadequate dietary fibre

• Infection/parasites

• Clostridial overgrowth 

• Parasites 

• Immune mediated / inflammatory

• eosinophilic, histiocytic, irritable bowel syndrome

• Neoplastic

• lymphosarcoma, adenocarcinoma

• Extra‐GIT (Secondary) causes

• hyperthyroidism, EPI, uremia, hypoadrenocorticismNot a complete list!

Some causes of diarrhea in cats and dogs

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• With a good history, you should hopefully be able to answer three things:

1. Does the patient actually have diarrhea?

2. Is it acute or chronic?

3. Is it small bowel or large bowel in origin?

The scoop on poop: summary of what we need to know to narrow the differential diagnosis

http://dogtime.com/trending/29357‐15‐best‐dog‐poop‐signs#/slide/2

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Investigating diarrhea:1. Does the animal actually have diarrhea?

https://en.wikipedia.org/wiki/Bristol_stool_scale

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Does the animal actually have diarrhea?

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So many stool charts…

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Investigating diarrhea:2. Is it acute or chronic? 

• With a good history, you should hopefully be able to answer three things:

• Does the patient actually have diarrhea?

• Is it acute or chronic?

• Acute ≤ 14 days

• Chronic ≥ 14 days

• Is it small bowel or large bowel in origin?

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Investigating diarrhea3: Small bowel or large bowel?

COMPLETE THE TABLE Small Bowel (duodenum to ileum)

Large Bowel (ileum and colon)

Fecal volume

Frequency of defecation

Straining to defecate (tenesmus)

Blood in feces

Mucous in feces

Fatty consistency to feces (steatorrhea)

Associated signs occasionally seen

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SmallBowel

LargeBowel

How much? fecal volume increased Decreased or normal

How often? Frequency of defecation increased Markedly increased

Any straining to defecate? (tenesmus) Absent Present

Appearance of blood in feces (if present)? Dark red‐black blood(Melena)

Fresh, red blood(Hematochezia)

Mucous in feces? Absent or small amount Large amount

Fatty consistency to feces? (steatorrhea) Present (some diseases only)

Absent

Other signs? Vomiting, weight loss, dehydration

Less weight loss, dehydration

LOCATION, LOCATION, LOCATION :Differentiating small vs large bowel diarrhea

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SmallBowel

LargeBowel

How much? fecal volume increased Decreased or normal

How often? Frequency of defecation increased Markedly increased

Any straining to defecate? (tenesmus) Absent Present

Appearance of blood in feces (if present)? Dark red‐black blood(Melena)

Fresh, red blood(Hematochezia)

Mucous in feces? Absent or small amount Large amount

Fatty consistency to feces? (steatorrhea) Present (some diseases only)

Absent

Other signs? Vomiting, weight loss, dehydration

Less weight loss, dehydration

LOCATION, LOCATION, LOCATION :Differentiating small vs large bowel diarrhea

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The scoop on poop: happy snaps

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• Four mechanisms of diarrhea: remember the poo poms!

• Permeability alterations

• Eg salmonella, parvovirus 

• Osmotic diarrhea

• Eg. rotavirus, EPI• Motility alterations

•Eg. hyperthyroidism, intussusception

• Secretory diarrhea

• Eg. ETEC (enterotoxigenic E. coli)

• Investigating small animal diarrhea:

• Does the patient have diarrhea?

• Acute vs chronic

• Small intestine vs large intestine

Summary

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