Pediatric small intestine bacterial overgrowth in low-income countries

• SIBO occurs when colonic quantities of commensals are present in the small bowel.
• SIBO is associated with unsanitary living conditions in developing-world children.
• SIBO may put developing-world children at risk for malnutrition and growth stunting.
• Gut immune disruption in SIBO may be linked to oral vaccine failure and celiac disease.

Small intestine bacterial overgrowth (SIBO) occurs when colonic quantities of commensal bacteria are present in the small bowel. SIBO is associated with conditions of disrupted gastrointestinal (GI) motility leading to stasis of luminal contents. Recent data show that SIBO is also found in children living in unsanitary conditions who do not have access to clean water. SIBO leads to impaired micronutrient absorption and increased GI permeability, both of which may contribute to growth stunting in children. SIBO also disrupts mucosal immunity and has been implicated in oral vaccination underperformance and the development of celiac disease. SIBO in the setting of the impoverished human habitats may be an under-recognized cause of pediatric morbidity and mortality in the developing world.