Introduction

Familial benign pemphigus, also called Hailey–Hailey disease, is a blistering disease caused by mutations in the ATP2C1 gene, with autosomal-dominant inheritance. The ATP2C1 gene is vital for keratinocyte adhesion and differentiation. Usually, the clinical presentation starts during the second or the third decade. The main affected areas are the skin folds, with moist fissured malodorous plaques and blisters. The course of the disease is variable, and treatment is mainly symptomatic.

Histology of benign familial pemphigus

In benign familial pemphigus, acantholysis affects the whole epidermis, giving the classic description of the dilapidated brick wall (figures 1–4). The hair follicles are usually spared, typically, with acanthosis and dyskeratosis.

Figure 1

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Special studies for benign familial pemphigus

Direct immunofluorescence is applied to fresh tissue to exclude an immunobullous disease, particularly pemphigus vulgaris.

Differential diagnosis of benign familial pemphigus

Grover disease: usually more focal histologically.

Pemphigus vulgaris: positive direct immunofluorescence and more likely to involve hair follicles.