HLA markers in familial Lichen sclerosus.

BACKGROUND

Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co-etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti-thyroid peroxidase autoantibodies (anti-TPO), a hallmark of autoimmune thyroid diseases.

PATIENTS AND

METHODS

In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR-SSP, and measurement of anti-TPO, free thyroxine and thyroidstimulating hormones (TSH) levels.

RESULTS

There were 8 cases of LS, 50 % of them anti-TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS.

CONCLUSION

New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti-TPO antibodies strongly suggests autoimmune thyroiditis. There is intra-familial association between the haplotype HLA-B*15 -DRB1*04 -DRB4* and anti-TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.