Hailey-Hailey disease is a rare genetic condition that is characterized by blistering or scaling of the skin, usually over the neck, skin folds, armpits and genitals. The condition usually becomes apparent between the ages of 15 and 40 years, although symptoms may develop at any age.

Hailey-Hailey disease occurs in 1 in 50,000 people, and affects men and women equally. The condition is inherited in a dominant pattern - there is a 50% risk that any child born to an affected parent will inherit it.

Hailey-Hailey disease is caused by the loss of adhesion between skin cells. This leads to the separation of cells in the epidermis, particularly in areas of skin that rub together, such as in the groins and underneath the arms.

The condition occurs due to a genetic mutation on chromosome 3. It affects the ATP2C1 gene that codes for a calcium-magnesium pump protein which is important to ensure that cells in the epidermis stick together properly. The condition is aggravated by factors such as heat, sweating, sunlight and friction.

Symptoms

Also referred to as familial benign pemphigus, Hailey-Hailey disease is characterized by blistering symptoms that are very similar to those seen in the pemphigus family. However, the pemphigus conditions are autoimmune diseases, whereas Hailey-Hailey disease is a genetic condition and does not involve the formation of autoantibodies.

Signs and symptoms of Hailey-Hailey disease include:

• A blistering skin rash that most commonly develops in the groin, armpits and neck
• Red scaly areas of skin
• Crusting of the exudate forming a fibrinous pseudomembrane over the lesion
• Itching and burning sensations of the affected areas
• Painful and cracked skin
• Infection of the lesions that may give rise to an unpleasant odor

The condition is one which remits and relapses, or in other words, the symptoms may resolve and then recur periodically. The period between a relapse and a remission varies. When lesions heal, they do not usually leave scars, and the skin appears completely normal between periods of disease activity.

Diagnosis

Hailey-Hailey disease may often be mistaken for eczema, a sweat rash, impetigo, or contact dermatitis. To confirm whether the condition is Hailey-Hailey disease, a skin biopsy is taken from the affected skin and examined under a microscope. A biopsy will show abnormal keratinization and separation of skin cells.

Treatment

Hailey-Hailey disease cannot be cured, but symptoms can be managed with treatment. Flare-ups tend to settle down within a few days with appropriate treatment. In many cases, the lesions resolve without any treatment if triggering factors are avoided.

When medication is required, a combination of a corticosteroid cream and an antibiotic may be used. When an exacerbation is imminent, immediate application of the corticosteroid cream is recommended to prevent the rash from worsening. Other treatment approaches include use of the botulinum toxin, which reduces sweating; surgical removal of affected skin areas; and laser treatment.

References

• http://www.britishskinfoundation.org.uk/SkinInformation/AtoZofSkinDisease/HaileyHaileydisease.aspx
• http://www.bad.org.uk/for-the-public/patient-information-leaflets/hailey-hailey-disease/?showmore=1#.VvFfdzG2B9k
• http://rarediseases.org/rare-diseases/hailey-hailey-disease/