The evolving understanding of prurigo nodularis.

Prurigo nodularis (PN) is a chronic, highly pruritic inflammatory skin disease that, until recently, was poorly understood. PN was first described in the late 1800s, but awareness of the disease remained low, probably because of its low prevalence and resemblance to other diseases. Interest in the research and therapeutic advancement of PN has grown in recent years, leading to a greater understanding by the medical community of its natural history, pathophysiology, diagnosis and treatment. We describe how our understanding of PN has evolved in recent years and how current therapeutic advancements have facilitated a greater appreciation of PN as a unique disease with a distinct pathophysiology.