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Published on: May 2, 2018

Mechanism of diarrhea in microscopic colitis

Marijana Protic1, Njegica Jojic, Daniela Bojic

  • 1Center for Gastroenterology and Hepatology, Zvezdara Clinical Center, Belgrade 11 000, Serbia and Montenegro. marijanaprotic@beotel.yu

World Journal of Gastroenterology
|October 14, 2005
PubMed
Abstract

Insights

Diarrhea in microscopic colitis (MC) is primarily secretory. In lymphocytic colitis (LC), reduced sodium absorption causes diarrhea, while collagenous colitis (CC) involves altered chloride transport.

Area of Science:

  • Gastroenterology
  • Pathophysiology
  • Colitis Research

Background:

  • Microscopic colitis (MC) presents diagnostic challenges.
  • Understanding the pathophysiology of MC-associated diarrhea is crucial for effective management.

Purpose of the Study:

  • To elucidate the pathophysiological mechanisms of diarrhea in microscopic colitis.
  • To differentiate between secretory and osmotic diarrhea in MC patients.

Main Methods:

  • Analysis of daily stool weights, fecal electrolytes (sodium, potassium, chloride), osmotic gap, and pH.
  • Inclusion of 51 MC patients (40 LC, 11 CC), 7 MC patients without diarrhea, and 18 controls.
  • Stool sample collection over 3 days with laboratory analysis.

Main Results:

  • Significantly increased fecal sodium in LC and CC compared to controls.
  • Significantly decreased fecal potassium in LC and CC compared to controls.
  • Elevated chloride concentration in CC.
  • 86.7% of MC patients exhibited secretory diarrhea based on fecal osmotic gap.

Conclusions:

  • Diarrhea in MC is predominantly secretory.
  • Reduced active sodium absorption is a key mechanism in LC.
  • In CC, decreased Cl/HCO3 exchange and increased chloride secretion coexist.

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