Histopathological findings, viral DNA distribution and lymphocytic immunophenotypes in vesicular and papular types of herpes zoster.

The characteristics rash of herpes zoster begins as erythematous macules and papules, progressing to vesicles within 12-24 h. Patients with persistent papules without vesicular change are occasionally found. Our aim was to elucidate differences in vesicular and papular types of herpes zoster. Biopsy specimens from 21 patients were examined by an in situ hybridization method to observe viral distribution, and lymphocytic immunophenotypes were evaluated immunohistochemically. There was no differences in cell-mediated immunity or immunophenotypes in lymphocytic infiltrates between vesicular and papular types of herpes zoster. DNA of varicella-zoster virus was detected in the epidermis and hair follicles in the vesicular type but was found in the pilosebaceous unit in the papular type. This indicates that the appearance of clinical types of herpes zoster depends on the infected site of varicella-zoster virus in the tissue.