CC: tongue swelling, drooling
ID: 40 yo woman with HTN, GERD, anxiety disorder presents with throat swelling, subjective fevers, and drooling for 3 days. She presented to an urgent care clinic 2 days ago with the same complaints and was given clindamycin without any improvement in her symptoms. Home medications included amlodipin, omeprazole, and paroxetine. She denied a family history of any swelling. A thorough workup, including C4, auto-antibodies, C1 esterase inhibitor levels and function all returned normal. She was finally deemed to have idiopathic angioedema after extensive evaluation for underlying rheumatologic and malignant disease
Don’t forget:
- Anaphylaxis can be diagnosed if any of the following 3 clinical criteria are met (this confers 95% specificity for anaphylaxis). Remember that respiratory compromise or hypotension are notable features in anaphylaxis.
- acute onset skin/mucosal involvement AND respiratory compromise or hypotension
- exposure to a likely allergen AND 2 of the following 4
- skin/mucosal involvement
- respiratory compromise
- hypotension
- persistent GI symptoms
- exposure to a known allergen AND hypotension
- Urticaria is localized areas of edema associated with pruritis and affects the superficial dermis. It is usually transient and evanescent (< 24 hrs). Angioedema is a deeper form of localized urticaria and affects the subcutaneous tissue, typically lasting slightly longer (48-72 hrs).
Pearls from morning report:
- Mast cell mediated angioedema is associated with urticaria, pruritis, flushing, bronchospasm, throat tightness and hypotension. Bradykinin mediated angioedema is NOT associated with urticaria or pruritis.
- Initial laboratory workup for angioedema should include: CBC, CMP, CRP, ESR, C4. Decreased C4 levels should prompt evaluation for C1 inhibitor deficiency – consider measuring levels of C1 inhibitor antigen and C1 inhibitor functional levels.
- Early complement deficiencies (C1, C2, C3) can predispose to autoimmune disease. Late complement deficiencies (C5 – C9) cause recurrent bacterial infections.
Random trivia:
Trauma can sometimes precipitate angioedema in a patient taking ACEi by way of direct tissue injury activation of bradykinin. Angioedema was first described by Dr. Heinrich Quincke (of “Quincke’s pulse” – a sign of aortic insufficiency) in 1882 and was postulated to have a hereditary basis by Sir William Osler in 1888.
Want to read more?
Urticaria and angioedema (Allergy, Asthma, & Clinical Immunology)
Urticaria and angioedema: A practical approach (American Family Physician)
References:
Zuraw BL. Clinical practice: Hereditary angioedema. N Engl J Med. 2008;359(10):1027-36.
Zuraw B, Bingham CO. An overview of angioedema: Pathogenesis and cause. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. (Accessed on February 1, 2017)