Gut Microbiota Profile and Functional Gastrointestinal Disorders in Infants: A Longitudinal Study

Abstract

Background/objectives: The gut microbiota is involved in modulating gastrointestinal function and consequently contributes to the manifestation of functional gastrointestinal disorders (FGIDs). The aim of the study was to analyze the composition of the gut microbiota in infants with functional gastrointestinal disorders (infantile colic, functional constipation, gastroesophageal reflux, functional diarrhea) according to age, environmental factors, and clinical manifestations.

Methods: The study involved the clinical and laboratory examination of 134 infants divided into two groups: group I (n = 82) with FGIDs according to Rome IV criteria, divided into four subgroups (infantile colic, functional constipation, gastroesophageal reflux, and functional diarrhea), and group II (n = 52) without FGIDs. To assess the composition of intestinal microbiota, a bacteriological analysis of fecal samples was performed.

Results: Infants with functional gastrointestinal disorders presented an imbalance of intestinal microflora, which was characterized by a significant decrease in the main representatives of acidifying flora represented by Lactobacillus, Bifidobacterium, and Enterococcus and high abundance of proteolytic microorganisms from the Enterobacteriaceae family such as Klebsiella species and Escherichia coli. In infants born by cesarean section or artificially fed, the incidence of functional gastrointestinal disorders and intestinal dysbiosis was significantly higher.

Conclusions: The imbalance of acidifying and proteolytic microbial composition in the gut could be the key to the occurrence of functional gastrointestinal disorders in the first year of life.

Keywords: acidifying flora; functional gastrointestinal disorders; infants; intestinal microbiota.