BG10 Herpes simplex virus infection in bullous pemphigoid: diagnostic and management implications

Abstract

Bullous pemphigoid (BP) is an autoimmune blistering disorder that may be complicated by concomitant infections, particularly herpes simplex virus (HSV)-1. BP predominantly affects older adults, with incidence increasing significantly with age. This presentation explores two cases of extensive severe BP where swabs taken from cutaneous bullous lesions tested positive for HSV-1. We also highlight the importance of considering early detection of secondary viral infection in extensive disease. One of the two cases had involvement of the oral cavity, where an oral swab was also positive for HSV-1. Both patients were subsequently treated with a combination of antiviral therapy and systemic corticosteroids, with clinical improvement observed. One of the two patients had difficult-to-treat disease with persistent positivity of HSV-1 on swabs from cutaneous bullae and she was put on aciclovir prophylaxis alongside her BP treatment. These cases raise the question of whether clinicians should maintain a high index of suspicion for HSV-1 infection in patients presenting with BP and adopt a low threshold for early lesion swabbing. It might be difficult to differentiate between HSV reactivation and occult colonization of HSV of the affected skin and mucosa. On the other hand, previous analytical studies suggest that early identification of HSV-1 in BP is crucial, as patients are often commenced on immunosuppressive therapies that may precipitate HSV reactivation, dissemination and associated complications if infection is unrecognized. Emerging evidence suggests that patients with BP may benefit from a prolonged antiviral course of up to 2 weeks to achieve complete viral eradication, instead of the standard 5-day antiviral course. Early recognition and appropriate management of HSV-1 may therefore improve outcomes in patients with BP.