Lichen Sclerosus Et Atrophicus

Lichen sclerosus et atrophicus is a relatively uncommon cutaneous disorder that may affect any area. There is a particular predilection, however, for involvement of the female genitalia. Although typically the patient is a middle-aged female, prepubertal females may also develop this disorder. Shirer and Ray (1987) stated that about 18 cases of familial LSA had been reported. They concluded that 'heredity plays a role in some, if not all, cases.' They and others reported instances of affected mother-daughter pairs. The eruption of LSA consists of ivory-colored, polygonal, flat-topped lichenoid papules. These papules may coalesce into plaques, which then become atrophic. Adults with vulvar LSA may have an increased risk of developing squamous cell carcinoma of the vulva. Carcinoma has not been known to occur in extragenital lesions. Friedrich and MacLaren (1984) found 13 instances of familial lichen sclerosis in the literature and added 2 families.

Clay et al. (1994) found an association between lichen sclerosis and a specific variable number tandem repeat (VNTR) polymorphism in intron 2 of the gene encoding interleukin-1 receptor antagonist (IL1RN; 147679).

Oyama et al. (2003) noted that HLA-subtype susceptibility and high rates of other autoimmune disorders suggest that autoantibodies to specific mucocutaneous antigens may be involved in the etiology of lichen sclerosis. The clinicopathologic similarities between lichen sclerosis and lipoid proteinosis (247100), which results from mutations in the ECM1 gene (602201), suggested that this protein may be an autoantigen in lichen sclerosis. By immunoblotting, IgG autoantibodies to ECM1 were found in 20 of 30 lichen sclerosis serum samples. The highest titer was 1 in 20. These samples, and those from 56 other patients with lichen sclerosis, showed immunoreactivity to the recombinant ECM1 protein; 6 of 85 control serum samples were positive. The findings suggested that specific humeral immune response to ECM1 may be involved in the etiology of lichen sclerosis and may offer help in disease diagnosis, monitoring, and approaches to treatment.