Endocrine Abstracts

Introduction: Bullous pemphigoid (BP) is an uncommon chronic, autoimmune, and subepidermal disease. It can be associated with drugs, u.v. irradiation, and X-ray therapy. There is a number of reports on bullous pemphigoid (BP) induced by DPP-IV inhibitors (vildagliptin, sitagliptin, saxagliptin). The enzyme DPP-IV degrades glucagon like peptide 1 (GLP-1), which is a potent stimulator of insulin production and secretion. DPP-IV (CD26), present as a cell surface molecule on immune cells, also plays an important costimulatory role in immune activation. We present a case of BP induced by vildagliptin.

Case report: A 59-year-old male patient who was diagnosed type 2 DM had initial HbA1c level of 12.90%. Initial therapy with premix biphasic aspart insulin bid was switched to metformin and vildagliptin 50/1000 mg combo pill bid after A1c level dropped to 5.7% at 9 months of insulin therapy, Five months after vildagliptin was started, tense vesicles 8–10 in number with an erythematous base developed over forearms and cruris. Histologic examination of lesions yielded BP. Oral antidiabetics was discontinued. He was followed up with diet alone. He did not adhere to the therapy of oral flantadin and azathioprine and topical steroid. But the lesions regressed spontaneously after cessation of antidiabetics. Clobetasol propionate cream bid was continued. A1c was 5.7% 5 months after discontinuation of vildagliptin and metformin.

Conclusions: In the literature onset of BP lesions took 10 days to 2 years. Mostly the patients were on combo therapy with metformin. The lesions improved dramatically after cessation DPP-IV inhibitors avoiding necessity for systemic treatment for BP. Elder males predominate. This is the first case of BP induced by DPP-IV inhibitors in Turkey.