Microbial composition and fecal fermentation end products from colicky infants – a probiotic supplementation pilot

Objectives: The etiology of infantile colic has remained unknown. The present study aimed to identify possible differences in the fecal microbial composition and metabolic end products between colicky and non-colicky infants and to examine whether an orally administered probiotic supplementation has any effect on the microbiota and relief in colicky symptoms. Subjects and methods: The study population consisted of nine colicky and nine non-colicky infants. Five colicky infants received probiotic supplementation (Lactobacillus rhamnosus GG, Lactobacillus rhamnosus LC705, Bifidobacterium breve Bbi99, and Propionibacterium freudenreichii ssp. shermanii JS) and four colicky infants received placebo for 2 weeks. Fecal microbiota of all infants was studied by culture, cellular fatty acid (CFA) analysis, and gas and short chain fatty acid (SCFA) production in 48 h fermentation. Microbial parameters and crying profiles were compared between the cases and controls at baseline and between the probiotic and placebo supplementation after 2 weeks. Results: Although SCFA and gas production and bacterial total counts were similar, the prevalence of indole-producing coliforms was significantly higher in colicky infants compared with controls (89% vs 33%), while many aerobic genera present in controls were not detected in colicky infants. CFA composition reflected the differences, since >2% of the CFAs were present exclusively in the colicky group. After probiotic supplementation, the total counts of anaerobic bacteria, especially lactobacilli and bifidobacteria, increased significantly. Fermentation parameters were not extensively affected; however, acetic and lactic acid production tended to increase and hydrogen production tended to decrease. No significant difference was observed in crying patterns between the probiotic and placebo group. Conclusion: The composition of the intestinal microbiota differs between colicky and non-colicky infants. Although no apparent relief in colicky symptoms was achieved, the probiotic supplementation seems to increase the bacterial diversity and strengthen the succession towards a balanced commensal gut microbiota.