An assessment of bacterial overgrowth and translocation in the non-alcoholic fatty liver of patients with morbid obesity.

BACKGROUND

small intestinal bacterial overgrowth (SIBO) and bacterial translocation across the intestinal wall have been allegedly associated with non-alcoholic fatty liver (NAFL). Our goal was to study such alleged association in morbidly obese patients.

PATIENTS AND METHODS

patients with morbid obesity were consecutively included prior to bariatric surgery. Exclusion criteria included normal liver biopsy, other causes of liver disease, and duodenal mucosal atrophy. A gastroscopy was performed for duodenal aspirate culture and duodenal biopsy, and peripheral venous blood was drawn to assess lipopolysaccharide (LPS) and LPS-binding protein (LBP) levels. A liver biopsy was carried out during surgery.

RESULTS

seventy-one patients were included; 26 were excluded because of normal liver biopsy. Forty-five had NAFL. Eighteen were male, mean age was 45.8 years (22-69), and BMI was 47.8 kg/m2 (37-58). A total of 25% had SIBO in their duodenal aspirate culture. There was statistical significance for the association of LBP levels and SIBO with steatosis grade (p < 0.05 and p = 0.077, respectively). There was no statistical association with non-alcoholic steatohepatitis (NASH) index, but a trend towards association was found. LPS levels were not associated with steatosis grade or NASH index.

CONCLUSIONS

the higher the grade of liver steatosis, the higher were the circulating LBP levels and SIBO rates seen in patients with morbid obesity and NAFL.