The prevalence of HLA-B7 in presumed ocular histoplasmosis in patients with peripheral atrophic scars.

Patients identified in the Walkersville, Maryland, epidemiologic study of presumed ocular histoplasmosis as having only peripheral atrophic scars showed no increase in frequency of HLA-B7 over a control population. Because this antigen is increased in patients with a history of active macular or peripapillary lesions, these findings indicate an inherent predisposition in some patients to develop posterior pole lesions after an ocular infection with Histoplasma capsulatum. The precise mechanisms by which the histocompatibility complex participates in the pathogenesis of these lesions is unknown, but our data are compatible with previous suggestions that alterations in the immune response of these individuals are in some way important in the development of disciform scarring in the posterior pole.