Exogenous insulin-derived acanthosis nigricans: could it be a cause of increased insulin requirement?

Acanthosis nigricans is a cutaneous manifestation of insulin resistance. We herein present a case of localized acanthosis nigricans over the abdomen in a 14-year-old boy with type 1 diabetes mellitus. The acanthosis nigricans appeared secondary to repeated insulin injection over same site. After advising the patient about rotating the injection site there was better disease control along with drop in insulin requirement and a significant reduction in the size of the lesion.