Baby fever, diarrhea with blood mucus, this situation is dangerous, should be promptly to the hospital to clarify the cause of the disease, consider may be ulcerative colitis, intussusception and other diseases, the doctor will be based on the baby’s specific situation to decide the treatment, the treatment includes medication, surgery and so on. 1. Ulcerative colitis: baby diarrhea with blood mucus may be caused by ulcerative colitis, in addition to the above symptoms, there may also be nausea, abdominal pain, abdominal distension and other symptoms, severe may lead to dehydration, electrolyte disorders, etc., so it is dangerous. The diagnosis can be clarified by doing routine blood test and routine stool test. After the diagnosis is clear, you can apply Liuzosulfapyridine, Mesalazine, Prednisone and other drugs under the guidance of the doctor for treatment. 2. intussusception: baby diarrhea with blood mucus may also be caused by intussusception, may be due to intestinal peristaltic rhythm disorder, in addition to the above symptoms, may also appear abdominal pain, abdominal mass and other symptoms, serious can be complicated by dehydration, electrolyte imbalance and toxic shock, so it is dangerous. It can be clearly diagnosed by doing routine blood test, routine stool test, abdominal ultrasound, etc. After the diagnosis is clear, it can be treated by needing to go through surgery. All of the above drugs need to be used under the guidance of a doctor, avoid self-medication. If the baby has fever, diarrhea with blood mucus and other uncomfortable symptoms, parents should take the baby to the hospital in time to avoid delay or cause adverse reactions.