Effectiveness of probiotics of children with chronic abdominal pain en bacterial overgrowth.

Background: Chronic abdominal pain is a common problem of school-going children and is one of the most frequent reasons to visit a pediatrician. Pathogenesis remains unclear. Recent studies have pointed to an underlying gut microbial mechanism for chronic abdominal pain. When the microbial population native to the large intestine migrates proximally into the small intestine, a shift in the host-gut microbial relationship occurs, known as small intestinal bacterial overgrowth (SIBO). Similar to children with chronic abdominal pain, children with SIBO complain of nausea, abdominal pain, flatulence, diarrhoea and constipation. Scarpellini et al. showed an association between small intestine bacterial overgrowth and irritable bowel syndrome in children. Therapeutic options are limited. Recent study results showed that 70% of children with chronic abdominal pain and small intestinal bacterial overgrowth have an improvement of symptoms after treatment with probiotics. Although these data are promising, the study group was small and it missed a control group.

Aim: The aim of this study is to compare the effect of probiotics on chronic abdominal pain and small intestinal bacterial overgrowth compared to placebo.

Methods: 70 children, aged between 8-18yrs, with chronic abdominal pain and bacterial overgrowth will be randomized to one of these treatments: probiotics or placebo. Primary outcome measures are the percentages of patients with complete remission of chronic abdominal pain after the treatment phase and at six and twelve months follow up. Secondary outcome measures is the presence of small intestinal bacterial overgrowth.

Children with chronical abdominal pain and small intestinal bacterial overgrowth supplemented with probiotics will show less abdominal pain compared to placebo.

Outcomes are assessed at:

t=0: baseline; before randomisation;

t=1: directly after finishing the treatment period;

t=2: six months follow up;

t=3: twelve months follow up.

The probiotics consist of a mixture of Bifidobacterium and Lactobacillus (8 grams of powder 4 x 10E9 cfu Bifidobacterium and Lactobacillus (Ecologic junior)). This has te be used once a day for 8 weeks.


The control group will receive a placebo (Placebo is a composition of rice starch, maltodextrins and vegetable protein, and contains no bacterial strains).