IntroductionLocalized involutional lipoatrophy of subcutaneous adipose tissue may develop due to subcutaneous injection of pharmaceutical preparations. The pathogenesis of this adverse drug reaction is unknown. The progression of localized involutional lipoatrophy ceases and occasionally it resolves after withdrawing the inducing agent. In case of localized involutional lipoatrophy due to subcutaneous insulin therapy, low-dose systemic corticosteroids may be curative despite ongoing insulin administration.Case presentationWe report a recurrence of insulin-induced localized involutional lipoatrophy at the abdominal wall in a 57-year-old Caucasian woman with type-1 diabetes on continuous subcutaneous insulin infusion. The first episode of insulin-induced localized involutional lipoatrophy two years previously had been cured by oral prednisone. The recurrence was treated immediately with 10mg prednisone once daily for five months, and was cured thereafter. The insulin analog preparation (Humalog™) and the insulin pump equipment (Accu-Chek Spirit™) applied were the same during both episodes. Both episodes were preceded by a temporary disturbance of the immune balance (the first episode by vaccination, the second episode through shingles).ConclusionsThis case confirms that insulin-induced localized involutional lipoatrophy in type-1 diabetes can occur again, and can be cured by systemic corticosteroids. We suggest that temporary disturbance of the immune balance may trigger this transitory idiosyncratic reaction in a susceptible individual.