Forty four years of dermatophytes in a Chicago clinic (1944-1988)

Data are presented on 39,270 cultures taken over a 44 year span (1944-1988) at the University of Chicago's Dermatology Clinic. In the mid 1940's Microsporum audouinii accounted for 60-80% of isolates. It gradually decreased over the next two decades and disappeared altogether in the 1970's. Trichophyton rubrum, rare in the 1940's accounted for over 60% of isolates in the mid-1960's only to be overtaken by T. tonsurans. This species, not isolated till the mid 1950's, became and remains the dominant dermatophyte at the present time. Both T. mentagrophytes and Epidermophyton floccosum increased in the 1970's and decreased later. Unusual circumstances resulted in clusters of T. verrucosum, T. terrestre, and T. schoenleinii isolates. Infections were associated with rural dairy workers, zoo handlers and immigrant families respectively. M. canis and M. gypseum were steady at a low rate throughout the entire period. Rare isolates included M. cookei, M. persicolor, M. racemosum, T. simii, T. soudanense, T. violaceum, and the soil keratinophile, Aphanoascus fulvescens.