Trichophyton concentricum in skin lesions in children from the Salomon Islands

Aim of the paper was to report cases of Tinea imbricata, a mycosis caused by the anthropophilic dermatophyte Trichophyton concentricum, observed in 2012 in Guadalcanal, the largest of the Salomon islands.

During 2012, several cases of Tinea imbricata, called bakwa by local people, were observed in the Little Samaritan Hospital in Guadalcanal. Skin scrapings collected from three young patients were examined in Italy to confirm the clinical diagnosis. The fungus grown on culture was morphologically identified and submitted to sequencing of the ITS1-ITS2 region.

The diagnosis obtained by visual inspection of the skin lesions, characterised by concentric and lamellar plaques of scale often involving large part of the body, was confirmed mycological investigations. A prevalence of 15% of Tinea imbricata in this population was hypothesized. The fungus grown on culture was morphologically identified as Trichophyton concentricum and identification was confirmed sequencing the ITS1-ITS2 region. Patients were treated with potassium permanganate solution soaked gauze followed by colloidal sulfur and salicylic acid cream application. However, the efficacy of the antifungal treatment was difficult to evaluate due to the poor compliance of the patients and the remoteness of the villages.

Italian clinicians and mycologists should be aware of this fungal infection because the increased number of international travels and of migration rise the spread of infections previously restricted to limited geographical areas.