Extra-Scalp Black Dot Ringworm Caused by Trichophyton tonsurans Among Contact Sports Players

Abstract

We describe here two patients with tinea corporis exhibiting black dot ringworm (BDR). A cluster of black dots was observed on the extensor surfaces of the extremities of two rather hairy male patients, a 15-year-old judo practitioner and a 26-year-old combined martial arts fighter, during treatment of tinea corporis with topical antimycotics. Direct KOH examination showed that the black dots were composed of degenerated hair with numerous arthroconidia and were indistinguishable from BDR of tinea capitis. Trichophyton tonsurans was isolated from the dots of both patients. Although they were diagnosed with tinea corporis, they required 2-3 months of treatment with oral terbinafine. Dermatologists should be aware that BDR can appear on areas of the skin other than the scalp.

Epidemiology of dermatophytosis in junior combat and non‐combat sports participants

“…tonsurans in 14 wrestlers in Adana, Turkey. The molecular type EvSO 3 (which corresponds to non‐transcribed spacer 1) has been previously described in the USA, Canada and Japan 10,22,23 . Notably, we reported that in both a clonal outbreak 10 and a longitudinal study, 19 the most common clinical presentation of T .…”

Tinea Gladiatorum: Epidemiology, Clinical Aspects, and Management

“…They substitute hair cells almost entirely and are visible inside the hair. Sometimes, it leads to hair breaking off at or below the mouth of the follicle, leaving the residual part inside the follicle, which gives an impression of black dots on a smooth, bald background and thus a black-dot ringworm” appearance [ 3 , 35 , 36 , 37 ].…”

“…In this particular region, TG can be divided into three major clinical types [ 6 ]: Black-dot ringworm type—a result of a hair invasion ( endothrix ) [ 37 ]. In dermoscopic assessment, they can be found as a “comma-shaped” hair—a short hair with homogenous pigmentation and thickness [ 49 , 50 , 51 ].…”

“…In dermoscopic assessment, they can be found as a “comma-shaped” hair—a short hair with homogenous pigmentation and thickness [ 49 , 50 , 51 ]. Rarely, it is reported on other body sites such as the trunk or extremities [ 37 , 52 , 53 ]; Seborrheic type—it can mainly be characterized by scalp scaling and the presence of crusts; Kerion celsi type—a rare inflammatory manifestation of tinea capitis which represents a delayed T cell-mediated hypersensitivity reaction. It is an intense immune response to the infection caused by dermatophytes which results in limited, infiltrated, suppurative, and tender lesions.…”

“…In dermoscopic assessment, they can be found as a “comma-shaped” hair—a short hair with homogenous pigmentation and thickness [ 49 , 50 , 51 ]. Rarely, it is reported on other body sites such as the trunk or extremities [ 37 , 52 , 53 ];…”