Differential Diagnosis for Functional Gut Symptoms and Anxiety with Resultant Diarrhea
Single Most Likely Diagnosis
- Irritable Bowel Syndrome (IBS): This diagnosis is the most likely due to the combination of functional gut symptoms (such as abdominal pain, bloating) and anxiety, which are common comorbidities with IBS. The resultant diarrhea further supports this diagnosis, as IBS can present with a predominant diarrhea subtype (IBS-D).
Other Likely Diagnoses
- Generalized Anxiety Disorder (GAD): Given the presence of anxiety, GAD could be a contributing factor to the gastrointestinal symptoms. Anxiety can exacerbate or contribute to the development of functional gastrointestinal disorders.
- Functional Dyspepsia: Although more commonly associated with upper gastrointestinal symptoms, functional dyspepsia can sometimes co-occur with IBS or have overlapping symptoms, including those that might lead to diarrhea in some cases.
- Somatic Symptom Disorder: This disorder involves one or more chronic physical symptoms (like gastrointestinal issues) that are distressing and result in significant disruption of daily life, with excessive thoughts, feelings, or behaviors related to the symptoms.
Do Not Miss Diagnoses
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can present with chronic diarrhea and abdominal pain. Although less likely than IBS given the description, missing IBD could lead to significant morbidity if not treated appropriately.
- Celiac Disease: An autoimmune disorder that can cause diarrhea, abdominal pain, and other gastrointestinal symptoms upon ingestion of gluten. It's crucial to rule out celiac disease due to its potential for serious complications if left untreated.
- Gastrointestinal Infections: Certain infections (bacterial, viral, or parasitic) can cause chronic diarrhea and must be considered, especially if there's a history of travel or exposure to contaminated food and water.
Rare Diagnoses
- Microscopic Colitis: A condition characterized by chronic, watery diarrhea, with microscopic evidence of colonic inflammation. It's less common than IBS or IBD but should be considered in the differential diagnosis of chronic diarrhea.
- Bile Acid Diarrhea: A condition where the body produces too much bile acid, leading to chronic diarrhea. It's a less common cause of diarrhea but can be considered if other diagnoses are ruled out.
- Neuroendocrine Tumors: Rare tumors that can produce substances leading to various symptoms, including diarrhea. Although very unlikely, they represent a potentially treatable cause of chronic diarrhea if identified.