A 32-year-old woman with a history of hypothyroidism presented to the emergency department after two days of worsening facial swelling and associated pruritus. The swelling began after resolution of a five-day episode of sinus congestion and severe pharyngitis while visiting family in another state. Her facial symptoms started with redness and left periorbital swelling (Figure 1) and gradually progressed to generalized facial swelling.

The patient’s family physician treated her with amoxicillin/clavulanate and a steroid. However, her symptoms worsened, and she went to the emergency department. She tested positive for group A streptococcal infection and COVID-19. The facial swelling continued to increase, and she returned to the emergency department the next day.

Physical examination revealed bilateral peri-orbital edema that was worse on the right side and mild facial erythema that had spread overnight (Figure 2).

Question

Which one of the following is likely causing this patient’s symptoms?

• A. Cellulitis.

• B. COVID-19.

• C. Myxedema.

• D. Poststreptococcal glomerulonephritis.

• E. Scombroid poisoning.