[Pemphigoid mimicking epidermolysis bullosa acquisita]

Subepidermal autoimmune bullous dermatoses form a clinical entity for which there is not always an individualized clinical and pathological description.

A patient presented with bullous skin disease of atypical nature. There was an almost total desepidermization of the legs, vast areas of erosion on the trunk and arms with a Nikolski sign in an area of healthy skin, buccal involvement, multiple milium cysts and ungueal dystrophies with nail loss.

This clinical presentation in this patient suggested acquired bullous epidermolysis. However, according to the recently defined clinical criteria for pemphigoid, the probability of correct diagnosis of pemphigoid was greater than 95 p. 100 since nearly three fourths of the major criteria were present. This diagnosis was confirmed by reference techniques (electron microscopy, indirect electron immunomicroscopy and immunoblotting). Thus, bullous autoimmune diseases of the dermoepidermal junction can be reliably differentiated on the bases of the clinical features, together with direct and indirect immunofluorescence on salt-split skin.