Objective  To explore the clinical efficacy of bifidobacterium R0033 and R0071 combined with lactase in treating chronic diarrhea due to lactose intolerance among infants, so as to provide new ideas and evidence for clinical treatment.

Methods From March 2023 to November 2023, 34 infants with lactose intolerance in Chongqing Health Center for Women and Children were recruited as study subjects. They were divided into control and observation group by random number table method, with 17 participants in each group. The control group received lactase treatment only for 1 week, while the observation group received bifidobacterium R0033 and R0071 plus lactase for 1 week. Their general information, the number of bowel movements and the duration of diarrhea pre- and post-intervention of two groups were compared, as well as the relative abundance and α-diversity index of the gut microbiota.

Results There were no significant difference in gestational age, birth weight, age at enrollment, gender ratio, mode of delivery, feeding method, and parental lactose intolerance ratio between two groups (P > 0.05). Compared with control group, there was no significant difference in terms of the number of daily bowel movements pre- and 1 week post-intervention in the observation group (P > 0.05), but the duration of diarrhea in the observation group was significantly shorter than that in the control group (P = 0.004). Compared with control group, there was no significant difference in the relative abundance of gut microbiota and the α-diversity index 1 week post-intervention in the observation group (P > 0.05).

Conclusion The intervention of bifidobacterium R0033 and R0071 combined with lactase may have certain effects on reducing duration of diarrhea among infants with lactose intolerance, but it had no significant effects on the composition and diversity of gut microbiota.