Small intestinal bacterial overgrowth as a cause of lactase deficiency

Aim. To establish the rate of lactase deficiency (LD) in patients with post-infectious irritable bowel syndrome (PI-IBS), to define a role of enteric bacteria in the pathogenesis of hypolactasia, and to evaluate the efficiency of probiotic therapy. Subjects and methods. Examinations were made in 386 patients with PI-IBS, including 112 (79.4%) women; mean age 33.9±9.1 years; disease duration 2.6±1.4 years. Rapid tests of small intestinal mucosa (SIM) biopsy specimens obtained from the duodenal retrobulbar segment were used to diagnose LD. Bacterial growth was estimated by a hydrogen breath test using a Н2 MICRO gas analyzer. Results. The patients with PI-IBS were revealed to have moderate and severe LD in 25.6 and 10.9%, respectively. All the patients with LD were detected to have small intestinal (SI) bacterial overgrowth (BOG). An inverse correlation was found between LD and the degree of SI BOG (r=-0.53; p