Considerations for defining and diagnosing generalized pustular psoriasis.

Generalized pustular psoriasis (GPP) is a rare, chronic skin disease, characterized by widespread pustules and erythema, often accompanied with systemic signs and symptoms. GPP flares occur episodically but may be protracted. Left untreated, GPP can be life-threatening. Despite being first reported over 100 years ago, definitions and diagnostic criteria for GPP have been inconsistent and varied due, in part, to its rarity and a limited understanding of its pathogenesis. As such, many patients with GPP face delays in diagnosis and subsequent treatment. This manuscript aims to increase the recognition of GPP and provide foundational considerations to aid in the definition and diagnosis of this disease.