Acrodermatitis continua.

A 54-year-old woman presented with a 5-year history of erythema and pustules on the distal portion of her left index finger. Acrodermatitis continua of Hallopeau is a rare, chronic, sterile pustular eruption affecting the distal aspects of the digits. It is often considered to be a variant of pustular psoriasis that tends to be resistant to both topical and systemic treatments for psoriasis.