Differential Diagnosis for the 18-year-old African-American Man

• Single most likely diagnosis
  • Sickle Cell Disease: This is the most likely diagnosis given the patient's history of hemoglobinopathy, anemia, episodes of musculoskeletal pain, and the presence of an ankle ulcer. The patient's age, ethnicity, and clinical presentation are consistent with sickle cell disease, which is a common cause of hemoglobinopathy in African-American individuals.
• Other Likely diagnoses
  • Sickle Cell Trait with another underlying condition: Although less likely, it's possible that the patient has sickle cell trait rather than the full disease, combined with another condition that could explain his symptoms and the ankle ulcer.
  • Sickle Beta-Thalassemia: This is another form of hemoglobinopathy that could present similarly to sickle cell disease, with anemia, pain episodes, and potentially ulcers due to sickling crises.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Osteomyelitis: The presence of a painful, undermined ulcer could indicate osteomyelitis, especially if the ulcer is not healing. This condition requires prompt diagnosis and treatment to prevent serious complications.
  • Deep Vein Thrombosis (DVT): Although less common in this age group, DVT could present with pain and swelling in the affected limb and is a potentially life-threatening condition if not diagnosed and treated promptly.
• Rare diagnoses
  • Other Hemoglobinopathies (e.g., Hemoglobin C Disease, Hemoglobin E Disease): These are less common forms of hemoglobinopathy that could potentially present with similar symptoms, although they are less likely given the patient's ethnicity and clinical presentation.
  • Pyoderma Gangrenosum: A rare skin condition that could cause ulcers, although it would be an unusual diagnosis in this context without other supporting evidence.