ABSTRACT

Certain dermatophyte infections are more common in different age groups. Scalp ringworm is found in children, but seldom persists beyond 16 years of age, whereas athlete’s foot often begins in late childhood, and is more frequent between the ages of 20 and 50 years, where there is often current infection of the groin as well, particularly in males.3 Dermatophytes are acquired from other humans (anthropophilic), either directly or indirectly, from animals such as cats, dogs, and rodents (zoophilic), or, uncommonly, from the soil (geophilic), where farm workers and gardeners may be exposed to these fungi.4 Anthropophilic dermatophyte infections, such as those of the toes and feet, are acquired by contact with infected desquamated skin scales. They are typically acquired in damp communal environments, such as swimming pools and any other shared bathing area. Inadequate drying of the toes allows the infection of tinea pedis (‘athlete’s foot’) to become established, resulting in for some individuals a chronic and distracting infection; there may be a genetic susceptibility to this infection. Fungi such as Scopulariopsis brevicaulis can be considered as ‘secondary invaders’, and infect toe nails that are dysmorphic, having been damaged by preceding or ongoing infection caused by a dermatophyte such as trichophyton.