For several months, a 60-year-old woman has had a rash on the right side of her groin, which her primary care provider diagnosed as a “probable yeast infection.” The patient was given a prescription for nystatin cream; when this did not help, she was prescribed a combination clotrimazole/betamethasone cream. Initial signs of improvement prompted her to continue application daily.
However, although the original rash cleared, other skin changes occurred in the area. These alarmed the patient’s primary care provider, who observed them during a follow-up exam. In response, the patient requested a referral to dermatology.
EXAMINATION
The entire right crural area is bright red and shiny. Multiple blood vessels are seen coursing over the surface of the area. There is no edema, increased warmth, or tenderness on palpation.
Punch biopsy shows marked epidermal atrophy and fails to show any evidence of cellular atypia.
What is the diagnosis?