Differential Diagnosis for Diarrhea Lasting 14 Days
Single Most Likely Diagnosis
- Infectious gastroenteritis: This is the most common cause of diarrhea lasting up to 14 days, often caused by viral infections such as norovirus or rotavirus, but also can be due to bacterial infections like Salmonella or Campylobacter. The duration and symptoms such as fever, abdominal cramps, and vomiting support this diagnosis.
Other Likely Diagnoses
- Irritable Bowel Syndrome (IBS): Although IBS is a chronic condition, its symptoms can sometimes be mistaken for an acute infectious process, especially if the patient has a recent onset. However, IBS typically presents with a mix of diarrhea and constipation, abdominal pain, and bloating.
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can present with chronic diarrhea, abdominal pain, weight loss, and sometimes blood in the stool. The onset can be gradual, and the diagnosis is often considered in patients with persistent symptoms.
- Food intolerance: Lactose intolerance, fructose malabsorption, or other dietary intolerances can cause prolonged diarrhea if the offending food is not identified and avoided.
Do Not Miss Diagnoses
- Clostridioides difficile infection: This bacterial infection can cause severe, prolonged diarrhea and is often associated with antibiotic use. It's crucial to consider this diagnosis due to its potential severity and the need for specific treatment.
- Giardiasis: An infection caused by the Giardia parasite, which can lead to chronic diarrhea if not treated. It's particularly important to consider in individuals who have been camping, drinking untreated water, or have been exposed to someone with the infection.
- HIV/AIDS: Diarrhea can be a symptom of advanced HIV infection. Although less common, it's a critical diagnosis not to miss due to the significant implications for treatment and management.
Rare Diagnoses
- Whipple's disease: A rare, systemic bacterial infection that can cause chronic diarrhea, weight loss, and abdominal pain. Diagnosis is often delayed due to its rarity and nonspecific symptoms.
- Tropical sprue: A rare condition characterized by chronic diarrhea and malabsorption, typically seen in individuals who have traveled to or live in tropical regions.
- Microscopic colitis: A condition causing chronic, watery diarrhea, often in older adults, with a diagnosis made by colonoscopy and biopsy.