Localized bullous pemphigoid after knee replacement surgery.

Bullous pemphigoid (BP) most commonly presents as widespread, itchy, tense blisters in older patients. Localized bullous pemphigoid is a less common form of BP that can be more difficult to diagnose because of its similarity to more common conditions such as allergic contact dermatitis or bullous cellulitis. Prompt recognition of localized BP is important so that appropriate treatment can be started. We present a 57-year-old woman who presented with pruritic tense bullae overlying the surgical scar from a knee replacement 6 months prior on her anterior right knee. This case illustrates the potential for localized BP to be triggered by surgical procedures.