A 31-year-old woman presented with multiple necrotic skin lesions on her nose, ears, and legs that had developed over a period of a few days. The lesions had begun as erythematous-bluish macules that soon became bullous and finally, after approximately 10 days, developed into thick necrotic plaques.
She had no history of underlying diseases or infections, but she described several days of exposure to cold after the heating in her home failed and outside temperatures dropped to 50°F (10°C).
What is the most likely cause of these necrotic plaques ?
