At age 1, a girl developed a blistery rash on the left side of her face. It was soon followed by a low-grade fever and modest malaise. All symptoms cleared within 2 weeks. Now, at age 4, she continues to experience similar, periodic outbreaks in the same location.
She has already been seen by various providers, including a dermatologist, and received several different diagnoses. The dermatologist scraped the rash and determined it to be a fungal infection. However, the recommended topical antifungal cream had no effect. At least 3 other providers (all nondermatology) called it cellulitis and treated with oral antibiotics, but these attempts also failed.
There are no active lesions at the time of this initial examination and no palpable adenopathy in the region. There is a large area of erythema in a macular pattern over the right cheek. No scarring is visible.
The patient later returns when a new outbreak occurs. This time, there are distinct blisters and reactive adenopathy in the adjacent nodal areas.
What’s the diagnosis?