Lichen sclerosus and granuloma annulare of the foreskin: a significant association.

Lichen sclerosus (LS) is considered to be a disease resulting of local immune dysregulation. A delayed-type hypersensitivity reaction and cell-mediated immune response are hypothesized to be the pathogenesis of granuloma annulare (GA). The case is presented of an uncircumcised 45-year-old man who developed lesions of LS and GA in his foreskin. Both processes were treated with circumcision. GA is rarely located in the foreskin. As far as we are aware, only one previous case presented this location. We describe herein for the first time LS associated with GA in the foreskin. Both processes have a common autoimmune pattern suggesting a link between them. Although we cannot exclude that comorbidity may be a coincidence, we think this combination of lesions is not just coincidental but significantly associated through immunopathological mechanisms.