Differential Diagnosis for a 5-year-old Boy with Abdominal Pain and Diarrhea
- Single most likely diagnosis:
- Infectious gastroenteritis: This is the most likely diagnosis given the patient's symptoms of abdominal pain, diarrhea (initially watery and then bloody), and the absence of fever. The presence of gross blood in the stool sample supports this diagnosis, as it is consistent with an infectious cause such as a bacterial or viral gastroenteritis.
- Other Likely diagnoses:
- Intussusception: Although less common, intussusception is a possible cause of abdominal pain and bloody diarrhea in children. It occurs when a part of the intestine telescopes into another part, leading to bowel obstruction and potentially ischemia.
- Inflammatory bowel disease (IBD): Conditions like Crohn's disease or ulcerative colitis can present with chronic diarrhea, abdominal pain, and bloody stools. However, they are less common in young children and typically have a more gradual onset.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed):
- Appendicitis: Although the patient's symptoms do not strongly suggest appendicitis (e.g., no fever, diffuse abdominal tenderness rather than localized tenderness), it is a critical diagnosis to consider due to the potential for severe complications if missed.
- Hemolytic uremic syndrome (HUS): This condition, often associated with E. coli infections, can lead to renal failure and is a life-threatening complication. The presence of bloody diarrhea increases the suspicion for HUS.
- Volvulus or bowel obstruction: These conditions can cause severe abdominal pain, vomiting, and bloody stools due to bowel ischemia. They require immediate surgical intervention to prevent complications.
- Rare diagnoses:
- Meckel's diverticulum: A congenital anomaly of the small intestine that can cause gastrointestinal bleeding, but it is less common and typically presents with painless rectal bleeding.
- Henoch-Schönlein purpura (HSP): A systemic vasculitis that can cause abdominal pain, diarrhea, and gastrointestinal bleeding, but it is often accompanied by a characteristic rash and arthritis.