Bullous Pemphigoid in a Patient with Longstanding Hailey-Hailey Disease Complicated by Eczema Herpeticum: Managing the Coexistence of Three Different Blistering Conditions.

: Hailey-Hailey disease (HHD), or chronic benign familial pemphigus, is a rare inherited acantholytic dermatosis, characterized by chronic, recurrent vesicles, erosions, and maceration in intertriginous sites. We present a case of a male patient with longstanding HHD who presented with an acute exacerbation characterized by the worsening of pre-existing lesions but also with the appearance of new large, tense bullae on an erythematous base in the areas of the groin (i.e., inguinal region), trunk, and arms, associated with intense pruritus. Blood work revealed eosinophilia. Histopathology and direct immunofluorescence were compatible with the diagnosis of bullous pemphigoid (BP). Indirect immunofluorescence showed positivity for autoantibodies to BP antigen 180. We started oral methylprednisolone, oral antihistamines, and local care with potassium permanganate baths, a potent corticosteroid, and fusidic acid, with resulting improvement of the lesions. The case was further complicated by the occurrence of eczema herpeticum, which was successfully treated with acyclovir. At the time of discharge from the hospital, the patient was medicated with a low dose of oral steroid and oral doxycycline. During a later examination, the lesions had totally disappeared, but the skin had some residual hyperpigmented patches and excoriated papules. This case was a diagnostic challenge due to the simultaneous occurrence of three distinct bullous diseases with different etiopathogeneses. To our knowledge, there are no other reports of the coexistence of HHD and BP in the literature.