Question
A four-month-old baby has been suffering from diarrhea for over twenty days, and the situation has not improved. The parents are very anxious and unsure of how to handle the situation.
Answer
Firstly, the color of a baby’s stool is related to the chemical changes of bile. When in the upper part of the small intestine, due to the action of bilirubin and biliverdin, the stool appears yellow-green; as the stool enters the colon, biliverdin is reduced back to bilirubin, and the color turns to yellow. For breastfed infants, since their stool is acidic, oxidative bacteria may convert bilirubin into biliverdin, so the normal stool of breastfed infants is slightly green. However, for formula-fed infants, since their stool is alkaline, bilirubin may further reduce to colorless urobilinogen, resulting in a lighter stool color. If a formula-fed infant excretes green stool, it may indicate accelerated intestinal peristalsis or inflammation, which could be a sign of diarrhea. In this case, if the child has been taking antibiotics, we need to consider whether the antibiotics have killed some beneficial bacteria in the intestines, leading to imbalanced flora and persistent diarrhea. At this point, it should be discontinued and probiotic preparations should be used instead.