The relationship between non-alcoholic fatty liver disease and small intestinal bacterial overgrowth among overweight and obese children and adolescents.

BACKGROUND: The increasing rate of obesity and overweight among children has highlighted nonalcoholic fatty liver disease (NAFLD) as the most common cause of chronic pediatric liver diseases. There are many publications supporting the idea that gut microbiota is altered in NAFLD. The aim of this study was to evaluate the prevalence of NAFLD among overweight and obese children with and without small intestinal bacterial overgrowth (SIBO) compared to a control group and to assess if intestinal dysbiosis represents a risk factor for NAFLD.

METHODS: One hundred and twenty-five overweight and obese children aged 10-18 years and 120 controls matched for age and gender were enrolled. SIBO was assessed by glucose hydrogen breath test (GHBT) in all subjects. NAFLD was assessed in all children using abdominal imaging and laboratory findings.

RESULTS: Of 125 obese children enrolled, 47 (37.6%) presented intestinal dysbiosis and 78 (62.4%) were SIBO negative. Only four (3.3%) controls were SIBO positive. NAFLD was detected in 28/47 (59.5%) of the SIBO positive obese group, compared to 8/78 (10.2%) of the SIBO negative obese group (p<0.001) and 0/120 (0%) controls (p<0.001). Children from the SIBO positive obese group had higher rates of elevated aminotransferases levels: aspartate aminotransferases (ASAT) (53.1% vs. 6.4%; p<0.001) and alanine aminotransferase (ALAT) (59.5% vs. 7.6%; p<0.001), hypertension (23.4% vs. 5.1%; p=0.002) and metabolic syndrome (44.6% vs. 9%; p=0.002) compared to the SIBO negative obese group.

CONCLUSIONS: Obese children with SIBO have an increased risk for developing NAFLD. The relationship between intestinal dysbiosis and diet can influence the gut-liver axis.