Mucocutaneous presentation of Kaposi sarcoma in an asymptomatic human immunodeficiency virus-positive man.

Kaposi sarcoma (KS) is a malignant proliferation of endothelial cells within the skin. The clinical presentation is characterized by clusters of violaceous macules and papules that often appear on the distal extremities or trunk with or without oral mucosal involvement. Mucocutaneous lesions are present at onset of diagnosis in a minority of cases.

Case report: acanthosis nigricans resulting from repetitive same-site insulin injections.

Although acanthosis nigricans (AN) may be associated with internal malignancies, a benign form is more common, and a subset of these is drug-induced. In this case, a solitary, hyperpigmented, acanthotic plaque developed on the right abdomen after daily, same-site injections of insulin over a six-month period. The lesion completely resolved eight months after insulin injections were rotated to other locations.