Differential Diagnosis for Bloody Stools in a 3-Year-Old with 4 Days of Diarrhea
Single Most Likely Diagnosis
- Infectious Gastroenteritis: This is the most common cause of bloody stools in children, especially when accompanied by diarrhea. Viruses, bacteria, or parasites can cause the infection, with common pathogens including norovirus, rotavirus, and bacterial infections like Shigella or Salmonella. The child's continued ability to eat and drink suggests a less severe form of the illness.
Other Likely Diagnoses
- Intussusception: Although more commonly associated with abdominal pain and vomiting, intussusception can cause bloody stools. It's a condition where a part of the intestine slides into an adjacent part, potentially cutting off blood supply.
- Food Allergy or Intolerance: Certain food allergies, especially to milk or soy in young children, can cause gastrointestinal symptoms including bloody stools.
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease or ulcerative colitis are less common in young children but can present with chronic diarrhea, bloody stools, and abdominal pain.
Do Not Miss Diagnoses
- Hemolytic Uremic Syndrome (HUS): Typically following a bacterial infection like E. coli O157:H7, HUS can lead to kidney failure and is characterized by the triad of hemolytic anemia, acute kidney injury, and thrombocytopenia. Bloody stools can be an initial symptom.
- Meckel's Diverticulum: A congenital anomaly of the small intestine that can cause painless, bloody stools due to the presence of ectopic gastric mucosa.
- Abusive Injury: Physical abuse can sometimes present with gastrointestinal symptoms, including bloody stools, due to trauma.
Rare Diagnoses
- Vasculitis: Conditions like Henoch-Schönlein purpura can cause gastrointestinal symptoms, including bloody stools, but are less common and typically accompanied by other systemic symptoms like rash and joint pain.
- Gastrointestinal Polyps or Tumors: Although rare in children, these can cause bloody stools and should be considered if other symptoms or findings are present.
- Congenital or Acquired Disorders of the Gastrointestinal Tract: Various rare conditions affecting the GI tract can lead to symptoms including bloody stools, such as congenital infections or malformations.