Seen in the ED: Lower Extremity Rash Resists Treatment

A rash presumed to be a possible fungal or bacterial infection on the legs and feet of a 62-year-old man has failed to improve after 10 days of treatment. What's your Dx?

Patient history: A 62-year-old man presents to the emergency department (ED) for a rash. He has been using over-the-counter topical medications for possible fungal and possible bacterial infection in his legs for about 10 days but feels as though the condition is getting worse. He is having itching and scaling but no fever or pain except in his bilateral ankles where skin cracking is most prominent and there is some weeping. He has never had this before. He denies other complaints.

Vital sings & physical examination. Vital signs are normal. Physical exam is otherwise normal except for the rash shown below.

Initial diagnostic testing.
Laboratory studies--complete blood count and basic metabolic panel results both normal.


What is the most likely diagnosis?