Defining dipeptidyl peptidase-4 inhibitors-related bullous pemphigoid: A single-centre retrospective study

Background Many studies have corroborated the association of dipeptidyl peptidase-4 inhibitors (DPP4i) use with bullous pemphigoid (BP). It has been speculated that this drug-induced variant presents with a different clinical spectrum than conventional BP. Objective To determine the prevalence of DPP4i-induced cases of BP and to evaluate whether gliptin-related BP has specific clinicopathological and immunological features. Methods We conducted a retrospective, observational study of BP cases attended at our centre between January 2000 and June 2020. Epidemiological, clinical, histopathological and laboratory data were collected. Results A total of 257 cases of BP were collected; 51 (24.3%) were on treatment with DPP4i. When analysing DPP4i-induced BP cases, generalized BP was the predominant pattern and scalp/mucosal involvement was found in 13 patients. Gliptin-related BP cases were associated to a decrease in the eosinophilic infiltrate (p = 0.000) and both the detection rate and concentration of anti-BP180 IgG were lower (p = 0.004, p = 0.001, respectively) than non-DPP4i cases. Limitations Retrospective, single-centre study. Conclusion Our large DPP4i-induced BP case series has highlighted that DPP4i-induced BP is characterized by generalized lesions and scalp involvement. Lower titres of anti-BP180 antibodies and a decrease in eosinophils infiltrating into the skin may be distinct features of DPP4i-related BP.