Endemic tinea imbricata--a study on Goodenough Island, Papua New Guinea.

Tinea imbricata was studied in 102 patients on Goodenough Island, Papua New Guinea. Trichophyton concentricum was isolated from 98 skin samples. Seven different clinical patterns of infection were distinguished: concentric, lamellar, lichenified , plaque-like, annular, palmar/plantar, onychomycosis. Hypopigmentation was a prominent feature of the infection. The disease was most common in male children or adult women. Relapse after therapy, including oral griseofulvin, in patients remaining in the area was the rule. There was no evidence to suggest that those affected were abnormally susceptible to skin infections. An ineffective immune response to the infection may well explain the high relapse rate after treatment and the extensive nature of the lesions. Other susceptibility factors, such as a genetic predisposition, may also be involved and account for the high prevalence of the infection in this area.