Бүліктің қабынуы (Bullous Pemphigoid)

Autoimmune disease of skin and connective tissue characterized by large blisters

Bullous pemphigoid (a type of pemphigoid) is an autoimmune pruritic skin disease that typically occurs in people aged over 60, that may involve the formation of blisters (bullae) in the space between the epidermal and dermal skin layers. It is classified as a type II hypersensitivity reaction, which involves formation of anti hemidesmosome antibodies, causing a loss of keratinocytes to basement membrane adhesion.

Clinically, the earliest lesions may appear as a hives like red raised rash, but could also appear dermatitic, targetoid, lichenoid, nodular, or even without a rash (essential pruritus). Tense bullae eventually erupt, most commonly at the inner thighs and upper arms, but the trunk and extremities are frequently both involved. Any part of the skin surface can be involved. Oral lesions are present in a minority of cases. The disease may be acute, but can last from months to years with periods of exacerbation and remission. Several other skin diseases may have similar symptoms. However, milia are more common with epidermolysis bullosa acquisita, because of the deeper antigenic targets. A more ring like configuration with a central depression or centrally collapsed bullae may indicate linear IgA disease. Nikolsky's sign is negative, unlike pemphigus vulgaris, where it is positive.

In most cases of bullous pemphigoid, no clear precipitating factors are identified. Onset of pemphigoid has also been associated with certain drugs, including furosemide, nonsteroidal anti inflammatory agents, DPP 4 inhibitors, captopril, penicillamine, and antibiotics. autoantibodies targeting dystonin, also called bullous pemphigoid antigen 1, and/or type XVII collagen, also called bullous pemphigoid antigen 2, which is a component of hemidesmosomes. A different form of dystonin is associated with neuropathy.]] Diagnosis consist of at least 2 positive results out of 3 criteria (2 out of 3 rule): (1) pruritus and/or predominant cutaneous blisters, (2) linear IgG and/or C3c deposits (in an n serrated pattern) by direct immunofluorescence microscopy (DIF) on a skin biopsy specimen, and (3) positive epidermal side staining by indirect immunofluorescence microscopy on human salt split skin (IIF SSS) on a serum sample. Routine H&E staining or ELISA tests do not add value to initial diagnosis.

Treatments include topical steroids such as clobetasol, and halobetasol which in some studies have proven to be equally effective as systemic, or pill, therapy and somewhat safer. Antibiotics such as tetracycline or erythromycin may also control the disease, particularly in patients who cannot use corticosteroids. A 2010 (updated in 2023) meta analysis of 14 randomized controlled trials showed that oral steroids and potent topical steroids are effective treatments, although their use may be limited by side effects, while lower doses of topical steroids are safe and effective for treatment of moderate bullous pemphigoid.

Bulbous pemphigoid may be self resolving in a period ranging from several months to many years even without treatment. Some sources report it affects men twice as frequently as women, while others report no difference between the sexes. Many mammals can be affected, including dogs, cats, pigs, and horses, as well as humans. It is very rare in dogs; on average, three cases are diagnosed around the world each year.

Animal models of bullous pemphigoid have been developed using transgenic techniques to produce mice lacking the genes for the two known autoantigens, dystonin and collagen XVII.