Patient's question:
My baby has had diarrhea for more than ten days, and the stool test showed no problems. She has a bowel movement 5-6 times a day, with yellow-green, runny stools. Sometimes, there are curds mixed in, and it's foamy.Doctor's answer:
Most pathogenic microorganisms enter the digestive tract through ingestion of contaminated water, food, or via contaminated hands. Diarrhea can be caused when the body's defense functions decline and a large number of microorganisms invade and produce toxins. For example, after rotavirus invades the intestine, it damages the intestinal villus cells, reducing the small intestine's ability to absorb water and electrolytes, leading to diarrhea. Additionally, insufficient secretion of secondary disaccharidases results in incomplete digestion of sugars in the intestinal lumen, which are then decomposed by bacteria in the gut, increasing the osmotic pressure of intestinal fluid. This further causes the loss of water and electrolytes, exacerbating diarrhea. Bacterial infections that cause diarrhea include enterotoxic colitis and invasive colitis. However, pathogenic Escherichia coli does not produce enterotoxins or invasive forces, and its pathogenesis remains unclear.