A Case of Herpes Zoster Simulating Pemphigus Vulgaris Flare

Pemphigus vulgaris is an autoimmune bullous disorder caused by autoantibodies directed against desmogleins. There is an increased risk for developing herpes zoster in pemphigus vulgaris due to the prolonged and high doses immunosuppressant therapy. Here, we present a 52-year-old female patient with extensive pemphigus vulgaris who developed herpes zoster while on treatment which resulted in a diagnostic confusion and a Tzanck smear acted as a lifesaver revealing both multinucleated giant cells and acantholytic cells. Hence, a prompt decision of reducing the immunosuppressant and initiation of IV acyclovir helped the patient to recover faster. This case highlights the relevance of simple bedside investigation like Tzanck smear and reminds the clinician once again to be open to all possibilities.