Possible Crosstalk Between Small Intestinal Bacterial Overgrowth (SIBO) and Atopic Manifestations-A Short Overview

Area of Science:

• Immunology
• Gastroenterology
• Allergology

Background:

• Small intestinal bacterial overgrowth (SIBO) is increasingly recognized for its influence on immune responses.
• SIBO may be associated with atopic disorders including bronchial asthma (BA), food allergies (FA), chronic spontaneous urticaria (CSU), and mast cell activation syndrome (MCAS).

Purpose of the Study:

• To conduct a structured literature search assessing the potential correlation between SIBO and the manifestation of atopic disorders.
• To evaluate the impact of SIBO on immune responses and allergic conditions.

Main Methods:

• Structured literature search.
• Analysis of SIBO prevalence in patients with various atopic disorders.
• Review of treatment outcomes for SIBO in conjunction with atopic diseases.

Main Results:

• SIBO prevalence was highest in patients with bronchial asthma (60-100%) and food allergies (50-87.5%).
• SIBO prevalence was 30.9% in mast cell activation syndrome and 27.9% in chronic spontaneous urticaria.
• Treating SIBO improved symptoms in bronchial asthma and mast cell activation syndrome, but not chronic spontaneous urticaria.

Conclusions:

• Evidence suggests a crosslink between SIBO and atopic manifestations.
• Bacterial overgrowth may trigger Th2 immune responses and increase interleukins (IL-4, IL-5, IL-13) involved in allergic reactions.
• The "gut-allergy axis" presents potential new therapeutic avenues for atopic conditions.