Dipeptidyl peptidase-4 inhibitors have been suspected to induce bullous pemphigoid (BP). The objective of this study was to compare the observed frequency of gliptin intake in a large sample of 1,787 BP patients diagnosed between 2012 and 2015 in France, with the expected frequency after indirect age standardization on 225,412 individuals extracted from the database of the National Healthcare Insurance Agency. The secondary objective was to assess the clinical characteristics and the course of gliptin-associated BP, depending on whether gliptin was continued or stopped. The observed frequencies of intake of the whole gliptin class and that of vildagliptin in the BP population were higher than those in the general population after age standardization (whole gliptin class: 6.0%; 95% confidence interval ¼ 4.9e7.1% vs. 3.6%, observed-to-expected drug intake ratio ¼ 1.7; 95% confidence interval ¼ 1.4e2.0; P < 0.0001; vildagliptin ¼ 3.3%; 95% confidence interval ¼ 2.5e4.1% vs. 0.7%, ratio ¼ 4.4; 95% confidence interval ¼ 3.5e5.7; P < 0.0001). The association of any gliptinþmetformin was also higher than in the general population, ratio ¼ 1.8 (95% confidence interval ¼ 1.3e2.4; P < 0.0001). Gliptin-associated BP had no specific clinical characteristics. Gliptin was stopped in 48 (45.3%) cases. Median duration to achieve disease control, rate, and delay of relapse were not different whether gliptin was stopped or continued. This study strongly supports the association between gliptin intake, particularly vildagliptin, and the onset of BP.

We report a case of major regression of multiple atypical melanocytic nevi with a vitiligoid reaction in a patient with metastatic melanoma who achieved long-lasting complete remission after ipilimumab therapy. In 2008, a 54-year-old man presented with a dysplastic nevus syndrome. The patient was diagnosed with a scalp ulcerated melanoma (Breslow index 5.1 mm and Clark level IV), which was removed surgically. Four years later in April 2012, the patient was diagnosed with a right parietal skin metastasis, brain, lymph nodes, and bilateral lung metastases. The patient was first treated with vemurafenib, which had to be stopped because of renal toxicity. Disease stabilization was achieved after the second line of treatment with immunotherapy (ipilimumab, four infusions). However, 6 months later, the lung metastases had progressed. The patient was treated with pulmonary stereotactic radiotherapy associated with a second cycle of ipilimumab. After 6 months, he achieved complete remission. Simultaneously, the patient presented a generalized regression of his nevi with a vitiligoid reaction, or halo nevus, associated with a vitiligo located on the hands and inguinal areas. Vitiligo is a frequent immune-related adverse event of immunotherapy. Immunotherapy-induced halo nevus reaction is much less frequent than vitiligo. It was associated in the two case reports from the literature and in our patient with a quick and long-lasting complete remission of nodes and visceral metastases. Therefore, it might correspond to a stronger antimelanocyte immune reaction, associated with a favorable prognosis. The generalized halo nevi reaction in our patient could be more important because of the two cycles of ipilimumab compared with a single one. In conclusion, this case report suggests that a major regression of multiple nevi on ipilimumab might be associated with immunotherapy response.