Kaposi varicelliform eruption in patients with autoimmune bullous dermatoses

Background: Viral superinfection of skin affected by preceding dermatosis has been studied extensively in eczema and reported anecdotally in pemphigus. Little is known about its involvement and complications in patients with other immunobullous diseases. Methods: To investigate clinical features and complications of viral superinfection in patients with immunobullous diseases, we performed a retrospective chart review. Results: We identified 12 patients with immunobullous diseases (linear immunoglobulin A bullous dermatosis, n = 2; pemphigoid, n = 3; pemphigus, n = 7) and superinfection by herpes simplex virus 1 (n = 9) or 2 (n = 3). Complications included inpatient hospitalization for intensive management of skin lesions during viral flare (n = 6), herpes keratitis (n = 1), and death due to sepsis (n = 1). Five patients previously had a skin swab negative for herpes simplex virus polymerase chain reaction before a positive test. Nine patients were taking systemic corticosteroids or corticosteroid-sparing agents at herpetic infection; two with linear immunoglobulin A bullous dermatosis and one with a new diagnosis of pemphigus vulgaris had not. Conclusions: Viral superinfection is a potentially serious complication in patients with immunobullous diseases. Clinicians should have a high index of suspicion for this phenomenon, even when patients are not otherwise immunosuppressed or when previous viral skin assays have been negative.