The role of the small bowel microflora in the development of secondary lactase deficiency and the possibilities of its treatment with probiotics

AIM: To estimate the incidence of secondary lactase deficiency (SLD) in patients with postinfectious irritable bowel syndrome (PIBS) and the value of the small bowel microflora in its development and to elaborate treatment options for SLD/MATERIAL AND METHODS: One hundred and thirty-eight patients with PIBS, including 112 (81.2%) women and 26 (18.8%) men, were examined. The patients' mean age was 33.9±9.1 years. The duration of the disease was 2.6±1.4 years. Lactase deficiency (LD) was diagnosed using the color scale to test biopsy specimens from the duodenal retrobulbar region. The bacterial overgrowth syndrome (BOS) was identified by a 2-hour lactulose (20 ml) hydrogen breath test. Sixty patients with moderate SLD were randomized to 2 groups: 1) 41 patients received basic therapy (mesim forte as one tablet t.i.d., no-spa, 40 mg, t.i.d.) and combined probiotic bifiform (Ferrosan) containing Bifidobacterium longum 107, Enterococcus faecium 107 as one capsule t.i.d. for 14 days. Group 2 patients (n=19) had basic therapy in combination with placebo/RESULTS: SLD was detected in 59.4% of the patients with PIBS, including 43.5 and 15.9% with moderate and severe forms, respectively. In all cases, SLD was accompanied by BOS in the small bowel lumen, as confirmed by the results of a hydrogen breath test [101±37 ppm (a normal value of <20 ppm)]. After a 14-day course of therapy with the combined probiotic bifiform, restoration of eubiosis in the small bowel lumen was achieved in 70.8% of the patients, as shown by the lesser degree of BOS (86.9±40.9 and 17.4±6.6 ppm before and after treatment, respectively; р<0.01) and by normalization of the lactase test (р<0.01). In the comparative placebo group, 68.4% showed no clear positive changes, SLD and BOS remained/CONCLUSION: The changes in the small bowel intraluminal microflora, which developed after prior intestinal infection, played a great role in the development of SLD. Bifiform belongs to the currently available probiotics and may be recommended to correct SLD in patients with PIBS resulting from the impaired microbiota of the small bowel and to prevent BOS.

secondary lactase deficiency, microflora, probiotic, bacterial overgrowth syndrome