A Warm, Tender, and Erythematous Medial Ankle Rash

Introduction. A woman in her 50s presented to her primary care physician with a painful rash of her medial right ankle for the past 1 to 2 days.

History. The patient’s past medical history included well-controlled non-insulin dependent type 2 diabetes mellitus, obesity, and controlled hypertension. Oral ibuprofen and topical steroids did not improve her rash. She had increased exercise for weight loss, but otherwise reports no inciting events. She denied recent travel, sick contacts, trauma, or history of similar symptoms. She denied fevers, chest pain, dyspnea, palpitations, weeping or draining skin lesions, blisters, pain with ankle movement, swelling, weakness or joint pain.

Vital signs were stable. Examination revealed a tender, warm 10 x 6 cm area of poorly demarcated homogeneous erythema over the medial right ankle. No edema, abscess, or drainage was noted. She had full ankle range of motion and negative Homan’s sign bilaterally. The remainder of the physical examination was unremarkable. Her Wells’ score was -2 indicating low pretest probability for deep vein thrombosis (DVT).

Diagnostic testing. A clinical diagnosis was made without laboratory or imaging studies.