Painful red patches that suddenly appear on the face or neck can have many causes.
They may be related to an allergic reaction, an infection, or another inflammatory skin condition.
In one documented medical case, however, doctors eventually identified a much rarer explanation: Sweet syndrome, also known as acute febrile neutrophilic dermatosis.
The patient sought medical care after developing tender, raised red lesions that spread rapidly across the face and neck.
Because the rash was painful and appeared suddenly, dermatology specialists became involved.
Reviewing the patient’s recent history, the medical team noticed that a new medication had been started shortly before the symptoms developed.
Since certain medications are known to trigger inflammatory skin reactions, the drug was discontinued while further testing began.