Hailey-hailey disease on sun-exposed areas

Hailey-Hailey disease: clinical, diagnostic and therapeutic update

Hailey-Hailey disease is a rare genodermatosis described in 1939, with an autosomal dominant inheritance pattern, characterized by compromised adhesion between epidermal keratinocytes. It has an estimated prevalence of 1/50,000, with no gender or race predilection. It results from a heterozygous mutation in the ATP2C1 gene, which encodes the transmembrane protein hSPA1C, present in all tissues, with preferential expression in keratinocytes. Mutations in the ATP2C1 gene cause changes in the synthesis of junctional proteins, leading to acantholysis. It usually begins in adulthood, with isolated cases at the extremes of life. It manifests as vesico-bullous lesions mainly in the flexural areas, which develop into erosions and crusts. Chronic lesions may form vegetative or verrucous plaques. Pruritus, a burning feeling and pain are common. It evolves with periods of remission and exacerbation, generally triggered by humidity, friction, heat, trauma and secondary infections. The diagnosis is based on clinical and histopathological criteria: marked suprabasal acantholysis, loosely joined keratinocytes, giving the appearance of a "dilapidated brick wall", with a few dyskeratotic cells. The acantholysis affects the epidermis and spares the adnexal epithelia, which helps in the differential diagnosis with pemphigus vulgaris. Direct immunofluorescence is negative. The main differential diagnoses are Darier disease, pemphigus vegetans, intertrigo, contact dermatitis, and inverse psoriasis. There is no cure and the treatment is challenging, including measures to control heat, sweat and friction, topical medications (corticosteroids, calcineurin inhibitors, antibiotics), systemic medications (antibiotics, corticosteroids, immunosuppressants, retinoids and immunobiologicals) and procedures such as botulinum toxin, laser and surgery. There is a lack of controlled clinical trials to support the choice of the best treatment.

Hailey-Hailey Disease: An Update Review with a Focus on Treatment Data

Hailey-Hailey disease is a rare blistering dermatosis first described in 1939 by the brothers Howard and Hugh Hailey. Its incidence is estimated at 1/50,000. The inheritance is autosomal dominant with complete penetrance, but a variable expressivity in affected family members. Clinically, Hailey-Hailey disease presents between the third and fourth decade as flaccid vesicles and blisters on erythematous skin, giving rise to erosions, fissures, and vegetations. Maceration and superinfections are frequent. The lesions are typically distributed symmetrically within intertriginous regions such as the retroauricular folds, lateral aspects of the neck, axillae, umbilicus, inguinal, and perianal regions. The disease is characterized by a chronic relapsing course with spontaneous remissions and multiple recurrences. Severe disease can be very frustrating and have a major psychological and social impact. Given the dearth of evidence-based guidelines and large clinical trials, the assessment of the efficacy and safety of treatments is difficult. Treatments include topical and systemic agents, and procedural therapy such as lasers and surgery. This review provides a systematic search of the literature with a focus on classical and emerging treatment options for Hailey-Hailey disease.