Gut Microbiota Dysbiosis and Role of Probiotics in Infant Colic

Abstract

Infant colic or excessive crying syndrome is a behavioral syndrome in 1- to 5-month-old infants involving long periods of inconsolable crying and fussing in otherwise healthy infants. Its etiology is unclear, but evidence regarding the implications of the infant gut microbiota is rising in importance. In this short review, we aim to expose recent findings on alterations in the microbiota of colicky infants which could trigger or facilitate infant colic, and summarize the clinical and mechanistical evidence of several probiotic formulations for the management of infant colic. The observed increase in the relative abundance of Enterobacteria in colicky babies may facilitate intestinal hypersensitivity due to their endotoxins, while also increasing the amount of intestinal gas, and thus, bloating and digestive discomfort. Also, an association between infant colic and a decrease in the relative abundance of protective bacterial groups such as bifidobacteria or lactobacilli has been pointed out by independent research groups. Therefore, it is not surprising that many clinical trials have explored the effects of supplementing the microbiota of colicky infants with probiotics due to their known effect in modulating gastrointestinal microbiota.