Differential Diagnosis for Chronic Diarrhea
Single Most Likely Diagnosis
- Irritable Bowel Syndrome (IBS): This is often considered the most likely diagnosis for chronic diarrhea due to its high prevalence and the fact that it can present with a variety of gastrointestinal symptoms, including chronic diarrhea, without an identifiable cause.
Other Likely Diagnoses
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause chronic diarrhea, along with other symptoms such as abdominal pain and weight loss.
- Lactose Intolerance: A common condition where the body is unable to digest lactose, a sugar found in milk, leading to chronic diarrhea after consuming lactose-containing products.
- Gastroesophageal Reflux Disease (GERD): While primarily known for causing heartburn, GERD can also lead to chronic diarrhea in some cases.
- Small Intestine Bacterial Overgrowth (SIBO): An overgrowth of bacteria in the small intestine can lead to chronic diarrhea, bloating, and abdominal pain.
Do Not Miss Diagnoses
- Celiac Disease: An autoimmune disorder where the ingestion of gluten leads to damage in the small intestine, causing chronic diarrhea, malabsorption, and potentially severe complications if left untreated.
- Giardiasis: An infection caused by the Giardia parasite, which can lead to chronic diarrhea and malabsorption if not properly treated.
- Colorectal Cancer: Although less common, chronic diarrhea can be a symptom of colorectal cancer, especially in older adults, making it crucial not to miss this diagnosis.
- HIV/AIDS: Chronic diarrhea can be a symptom of HIV/AIDS, particularly in the advanced stages of the disease.
Rare Diagnoses
- Whipple's Disease: A rare, systemic bacterial infection that can cause chronic diarrhea, weight loss, and malabsorption.
- Tropical Sprue: A rare condition that affects the small intestine's ability to absorb nutrients, leading to chronic diarrhea and malabsorption, typically seen in people who have spent time in tropical regions.
- Short Bowel Syndrome: A condition where a significant portion of the small intestine is missing or not functioning, leading to chronic diarrhea and malabsorption.
- VIPoma: A rare tumor that produces vasoactive intestinal peptide (VIP), leading to chronic, watery diarrhea and other symptoms.