Hailey-Hailey disease: A fold (intertriginous) dermatosis.

Hailey-Hailey disease, also called benign familial pemphigus, is a late-onset blistering disorder that affects the flexures. There are typically painful erosions and cracks in affected areas. Lesions generally begin between 20 and 40 years of age. In two third of all cases, positive family history is detected. In pathogenesis, there is a defect in keratinocyte adhesion due to ATP2 C1 gene mutation. The result of the desmosomal decomposition is acantholysis. Menstruation, pregnancy, skin infections, physical trauma, excessive sweating and exposure to ultraviolet radiation are important triggering factors. Histopathologic changes are suprabasal acantholysis and formation of intraepidermal bullae. In the epidermis, a partial acantholysis that looks like broken bricks is observed.