Advances in knowledge on microscopic colitis: From bench to bedside

Area of Science:

• Gastroenterology
• Immunology
• Pathology

Background:

• Microscopic colitis (MC) encompasses lymphocytic colitis (LC) and collagenous colitis (CC), characterized by chronic watery diarrhea and distinct histopathological findings.
• Epidemiological data suggests MC is a global condition, though its etiopathogenesis remains unclear.
• Potential triggers include infections, drugs, autoimmunity, and bile acids, alongside impaired colonic epithelial barrier function.

Purpose of the Study:

• To review the current understanding of microscopic colitis pathogenesis.
• To highlight the role of immune responses and mucosal factors in MC.
• To discuss current treatment approaches and future research directions.

Main Methods:

• Review of epidemiological studies on MC prevalence.
• Analysis of research on MC etiopathogenesis, focusing on immune mechanisms.
• Examination of studies investigating mucosal factors and epithelial barrier function.
• Assessment of current therapeutic strategies and their limitations.

Main Results:

• MC is a multifactorial disease likely stemming from abnormal immune reactions in susceptible individuals.
• Evidence points to impaired epithelial barrier function and aberrant T-lymphocyte responses in MC pathogenesis.
• A predominant Th1 cytokine profile is observed in MC, indicating specific inflammatory mediators.

Conclusions:

• Further research is required to elucidate the molecular mechanisms underlying MC.
• Prospective, evidence-based studies are needed to refine understanding and develop targeted treatments.
• A better grasp of MC's origins could lead to causal therapeutic approaches.