Differential Diagnosis

The patient's symptoms, including cobblestone tongue, skin malar rash, chronic right-sided abdominal pain, thickening of the bladder wall, previous anal fistula, and poluria, suggest a complex condition with multiple system involvement. Here's a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • Crohn's Disease: This condition is a type of inflammatory bowel disease (IBD) that can cause chronic abdominal pain, anal fistulas, and extraintestinal manifestations such as skin rashes and bladder issues. The cobblestone appearance of the tongue can be associated with oral manifestations of Crohn's disease.

• Other Likely Diagnoses

  • Ulcerative Colitis: Another form of IBD, which primarily affects the colon and can cause similar symptoms, including abdominal pain and extraintestinal manifestations. However, the presence of a previous anal fistula and the specific pattern of abdominal pain might lean more towards Crohn's disease.
  • Systemic Lupus Erythematosus (SLE): This autoimmune disease can cause a malar rash, kidney issues (potentially leading to poluria), and various other systemic symptoms. However, the gastrointestinal symptoms and anal fistula are less typical for SLE.
  • Behçet's Disease: A form of vasculitis that can cause a wide range of symptoms, including oral ulcers (which might resemble a cobblestone tongue), skin lesions, gastrointestinal symptoms, and genitourinary issues. However, the specific combination of symptoms, especially the chronic abdominal pain and anal fistula, is less characteristic.

• Do Not Miss Diagnoses

  • Cancer (e.g., Colon or Bladder Cancer): Chronic abdominal pain, changes in bladder wall thickness, and previous anal fistula could be indicative of a malignancy. Although less likely given the patient's other symptoms, missing a diagnosis of cancer could be devastating.
  • Infectious Diseases (e.g., Tuberculosis): TB can cause a wide range of systemic symptoms, including chronic abdominal pain, bladder issues, and skin rashes. It's essential to consider infectious causes, especially in areas where TB is prevalent.

• Rare Diagnoses

  • Ehlers-Danlos Syndrome: A group of disorders that affect connective tissues supporting the skin, bones, blood vessels, and many other organs and tissues. While it could potentially explain some of the patient's symptoms, it's a less likely cause for the specific combination presented.
  • Sarcoidosis: An inflammatory disease that affects multiple organs in the body, but it would be an unusual cause for the specific gastrointestinal and genitourinary symptoms described.