Images in clinical medicine. "Half-half" blisters.

A 66-year-old man presented with an acute pustular eruption. On examination, an annular rash with multiple blisters was seen on the patient's trunk; the blisters contained both clear and yellow fluid. He had no associated cutaneous or systemic symptoms, and there was no facial or mucosal involvement. Examination of a biopsy sample taken from a representative blister revealed a subcorneal vesicle and other features characteristic of a subcorneal pustular dermatosis. Direct immunofluorescent staining showed IgA deposition in the superficial epidermis. Subcorneal pustular dermatosis is a chronic pustular dermatosis that frequently affects the flexures of the trunk and limbs. The face . . .