Cutaneous indurated plaque on the abdomen associated with diabetes mellitus

A woman, 74 years of age, presented to the emergency department with a lesion on the lower abdominal wall that had started a month earlier and was not associated with any other symptoms. Her family physician had treated it with emollient creams. Relevant past medical history included congestive heart failure, hypertension, hypertensive heart disease, pulmonary hypertension, mitral regurgitation, chronic atrial fibrillation, rosacea and diabetes mellitus that was being treated with oral hypoglycaemics (metformin). Physical examination revealed an area of skin on the lower abdominal wall that was ill-defined and indurated, with whitish papules and a 'cobblestone' appearance (Figure 1).