Abstract: Objective    To study the correlation between the changes in the content of individual bile acid components in the feces of infants who are exclusively breastfed and the frequency of defecation， in order to find the differential metabolites of bile acid which regulate the defecation frequencies of infants and provide beneficial suggestions for clinical intervention. Methods    Totally 102 healthy，full-term，exclusively breastfed infants aged 0.5-6 months were selected，who underwent health consultations and regular check-ups at the Pediatric Outpatient and Preventive Health Care Department of the First Affiliated Hospital of Kunming Medical University from September 2022 to May 2023.Fecal specimens were collected from these infants and categorized into three groups based on different defecation frequencies.The groups included the increased defecation frequency group（defecating more than 3 times per day， Group A，n=34），the decreased defecation frequency group（defecating once in more than 3 days or needing assistance to defecate， Group B，n=32），and the control group（defecating less than or equal to 3 times per day or defecating once within 3 days，Group C，n=36）. The content of bile acids was detected in feces by UPLC-MS/MS. Results    Chenodeoxycholic acid levels were significantly higher in group A than in groups C and B （P<0.017）， Ursodeoxycholic acid levels were significantly higher in group B than in groups C and A （P<0.017）. The difference in deoxycholic acid and lithocholic acid were statistically significant between group A and group B （P < 0.017）. When comparing the levels of cholic acid and glycochenodeoxycholic acid among the three groups， no statistically significant difference was found. Conclusion Chenodeoxycholic acid and ursodeoxycholic acid may serve as potential differential metabolites associated with increased or decreased defecation frequency in exclusively breastfed infants.

Key words: breastfeeding, infants, defecation frequency, fecal metabolites, bile acids

摘要： 目的    探讨纯母乳喂养婴儿粪便中各胆汁酸成分含量变化与不同排便频次之间的关系，进一步寻找调节婴儿排便频次的胆汁酸差异代谢物，为临床干预提供有益的建议。方法    选取2022年9月至2023年5月昆明医科大学第一附属医院儿内科门诊及预防保健科进行健康咨询及正常体检的0.5～6月龄健康足月纯母乳喂养婴儿102例，采集婴儿粪便标本，根据排便频次划分为3组：排便频次增多组（A组，每日排便>3次）34例；排便频次减少组（B组，超过3 d排便1次或需辅助才排便）32例；对照组（C组，每日排便≤3次或3 d以内排便1次）36例。通过超高效液相色谱质谱联用技术检测粪便中的胆汁酸含量。结果    A组鹅脱氧胆酸含量显著高于C组和B组，差异有统计学意义（P<0.017）；B组熊脱氧胆酸的含量显著高于C组和A组，差异有统计学意义（P<0.017）；脱氧胆酸、石胆酸在A组与B组之间比较，差异有统计学意义（P<0.017）；各组间胆酸、甘氨鹅脱氧胆酸的含量比较，差异均无统计学意义（P>0.017）。结论    鹅脱氧胆酸、熊脱氧胆酸可能作为差异代谢物与纯母乳喂养婴儿排便频次增多、减少有关。

关键词: 母乳喂养, 婴儿, 排便频次, 粪便代谢物, 胆汁酸