When two truths collide: overlapping herpes zoster and leukocytoclastic vasculitis in an atypical presentation

This case illustrates a diagnostically challenging presentation in which two distinct pathologies mimicked and masked one another. Anchoring on a unifying diagnosis led to premature closure, delaying antiviral therapy. Herpes zoster without vesicles is uncommon but documented, and VZV-induced vasculitis is rare. Together, they created a deceptive clinical picture. The case reinforces several key teaching points: the value of maintaining diagnostic flexibility, the importance of empiric antiviral treatment when herpes zoster is suspected, and the need to recognize cognitive biases that can distort clinical judgment. When findings are discordant or incomplete, clinicians should resist diagnostic simplification and remain open to diagnosing coexisting conditions.