Differential Diagnosis for a 9-week-old Baby with Diarrhea, Blood Clot in Stool, and Fatigue
- Single Most Likely Diagnosis
- Allergic proctocolitis: This condition is a common cause of rectal bleeding in infants, often associated with cow's milk protein allergy. The presence of blood clots in the stool and diarrhea, along with the age of the baby, makes this a plausible diagnosis. Fatigue could be secondary to the gastrointestinal symptoms and potential anemia from chronic blood loss.
- Other Likely Diagnoses
- Infectious gastroenteritis: Viral or bacterial infections can cause diarrhea and, less commonly, blood in the stool. The fatigue could be due to dehydration and the infection itself.
- Intussusception: Although more commonly associated with abdominal pain and currant jelly stool, intussusception can present with diarrhea and blood clots. It's a significant condition that needs early diagnosis.
- Do Not Miss Diagnoses
- Intestinal intussusception: As mentioned, this condition requires urgent diagnosis and treatment to prevent complications like bowel ischemia and necrosis.
- Hirschsprung's disease: Although typically diagnosed earlier, Hirschsprung's disease can present with enterocolitis, leading to diarrhea, blood in the stool, and systemic symptoms like fatigue.
- Volvulus or malrotation: These conditions can cause intestinal obstruction and ischemia, leading to severe symptoms including bloody stools and potentially life-threatening if not promptly addressed.
- Rare Diagnoses
- Congenital infections (e.g., CMV): These can cause a range of symptoms including gastrointestinal issues, but are less common.
- Inflammatory bowel disease (IBD): Although rare in infants, IBD (like Crohn's disease or ulcerative colitis) can present with diarrhea, blood in the stool, and systemic symptoms like fatigue.
- Hemolytic uremic syndrome (HUS): Typically follows a bacterial infection like E. coli, leading to renal failure and microangiopathic hemolytic anemia. It's rare but critical to diagnose early due to its severity.