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What is Hailey–Hailey disease and explain in detail?
Hailey–Hailey disease, or familial benign chronic pemphigus: 559  or familial benign pemphigus,: 622  was originally described by the Hailey brothers (Hugh Edward and William Howard) in 1939. It is a genetic disorder that causes blisters to form on the skin.

Signs and symptoms
HHD is characterized by outbreaks of rashes and blisters on the skin. Affected areas of skin undergo repeated blistering and inflammation, and may be painful to the touch. Areas where the skin folds, as well as the armpits, groin, neck, buttocks and under the breasts are most commonly affected