Differential Diagnosis for Facial and Tongue Swelling

The patient's presentation of facial and tongue swelling, followed by treatment with hydrocortisone, suggests an allergic reaction. Given the context, the likely culprit is a medication that the patient has been taking. Here's a categorized differential diagnosis:

• Single most likely diagnosis
  • B) Lisinopril: An ACE inhibitor, known to cause angioedema, a condition characterized by rapid swelling of the dermis, subcutaneous tissue, mucosa, and submucosal tissues. It's a well-documented side effect of ACE inhibitors, making Lisinopril a prime suspect in this scenario.
• Other Likely diagnoses
  • A) NSAIDS: Nonsteroidal anti-inflammatory drugs can cause allergic reactions, including angioedema. However, they are less commonly associated with this specific side effect compared to ACE inhibitors.
  • C) ARBs: Angiotensin II receptor blockers are less likely to cause angioedema compared to ACE inhibitors but cannot be entirely ruled out, especially if the patient has been switched from an ACE inhibitor to an ARB.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Hereditary Angioedema: A rare genetic disorder that can cause recurrent episodes of angioedema. Although unlikely, missing this diagnosis could be fatal due to the risk of airway obstruction.
  • Anaphylaxis: A severe, life-threatening allergic reaction that requires immediate medical attention. While the presentation might not fully align with anaphylaxis, the potential severity warrants consideration.
• Rare diagnoses
  • Allergic reactions to other medications: Various medications can cause allergic reactions, including angioedema. Examples include certain antibiotics, aspirin, and other drugs.
  • Idiopathic Angioedema: Angioedema without an identifiable cause, which could be considered if no medication or hereditary cause is found.