Approche clinique de la diarrhée

Question 1

What are the 4 mechanisms of diarrhea?

Answer 1

1. Osmotique
2. Sécrétoire
3. Inflammatoire
4. Motrice

Question 2

What is osmotic diarrhea?

Answer 2

Decreased absorption

Caused by the presence of osmotically active sustances that aren’t absorbable in the intestinal lumen

• stop when pt is “à jeun”
• Intestines are normal
• Gap osmotique dans les selles : normally = 2(Na+K) = 300 but if osmotic diarrhea < 250

Question 3

What causes osmotic diarrhea?

Answer 3

Malassimulation des nutriments: maldigestion (insuff. pancréatique, déficit en disaccharidases) ou malabsorption

ou

Malassimilation des produits ingérés non-absorbables: Mg, lactulose, sorbitol

Question 4

Tests for osmotic diarrhea?

Answer 4

Imager pancréas

Imager et investigation grêle

Dosage des graisses fécales

used to confirm dx

Question 5

What is secretory diarrhea?

Answer 5

Increase in secretions

Caused by abnormal ionic transport in intestinal epithelial cells

Selles: gap osmotique absent

Ne cesse pas avec le jeûne

Question 6

What causes secretory diarrhea?

Answer 6

Toxins

Villous adenoma

Hormones (VIP, carcinoids)

Bile salts

Question 7

Tests for secretory diarrhea?

Answer 7

Coloscopie

Octréoscan

Dosage hormonal

Question 8

What is motor diarrhea, causes, and tests?

Answer 8

Diarrhea post-prandiale

Causes:

• IBS
• Post-vagotomie
• Fécalome, néo colique

Tests:

• Éliminer lésions
• Éliminer autres causes

Question 9

What is inflammatory diarrhea, causes, and tests?

Answer 9

Diarrhea caused by exsudation

Cesse pas avec le jeûne

Causes:

• Infections: bacteria and parasites
• Inflammation: MII

Tests:

• Analyse des selles –> 2-3 times
• Imagerie du grêle
• Coloscopie

Question 10

Acute vs. chronic diarrhea:

Answer 10

Acute:

• Début: il y a 1-3 jours

Chronique:

• Début: > 2-3 weeks

Question 11

Ddx of acute diarrhea:

Answer 11

Infection: bacteria, protozoa, parasite, viral

Rx

Ingestion of non-absorbable sugars

Fecaloma –> blocked and only water can leave

Intestinal Ischemia

Question 12

Evaluation of acute diarrhea:

Answer 12

Fecal examination: culture, looking for parasites, and C. diff toxins

Formule sanguine complète

Ions, urée, créatinine
Coloscopie

Rx de l’abdomen (paroi épaisse, distention, mégacolon)

Question 13

Tx of acute diarrhea:

Answer 13

Hydratation

Tx causal

Tx symptomatique:

• Dim. transit, ex: Immodium
• Mais faire attention dans certains cas

Tx empirique avec ATB

Question 14

Ddx of chronic diarrhea:

Answer 14

• IBS
• MII
• Cancer
• ATCD de Chx
• Endrocrinopathy (ex: hypo t4)
• Rx
• Malabsorption
• Infection (usually parasites)

Question 15

Evaluation of chronic diarrhea:

Answer 15

CBC

Sedimentation

Ions, urea, creatinine

Albumin, Ca, Fe, folate, vit. A/B12/D, INR

TSH

Fecal examination –> parasite?

Coloscopie (maybe with biopsies… depending on cause)

Question 16

Overview of acute diarrhea:

Answer 16

Infection until otherwise proven incorrect

Rx to maintain equilibrium and dim. transit (if symptomatic)

If more than 3-4 days… fecal culture, ATB

Question 17

Overview of chronic diarrhea:

Answer 17

Can be quite complex

DDx according to classification

Investigation also according to ddx

Rx is targeted to the dx