What role does the microbiome play in infantile colic?

Alterations to the gut microbiota, whether from the presence of fats and other nutrients or because of other factors, may contribute to colic.^[1] Gut inflammation and an altered, less diverse gut microbiome may be important in some cases. In particular, infants with colic have been found to have higher amounts of Escherichia coli and Klebsiella species, and lower amounts of Lactobacilli.^[2][3][4] Furthermore, infants who have been treated with antibiotics may have a higher risk of colic, though the evidence is mixed.^[5][6][4] While not directly associated with colic,^[7][8][4] cesarean section deliveries alter the infant’s gut microbiome.^[9][10][11] Treatment of cesarean-delivered infants with probiotics may help their colic,^[12] showing that possibly the delivery method, and more likely the gut microbiome, are potential contributing factors to colic.^{[13][14][15][16]}