Abstract: 【Abstract】 To report 4 cases of skin infections caused by Neoscytalidium dimidiatum. Case 1, a 56-year-old female, presented with keratosis and thickening of both palms accompanied by mild pruritus for 20 years; case 2, a 50-year-old female, exhibited keratosis and desquamation of both soles and toes for 1 year; case 3, a 59-year-old male, presented with desquamation of both palms and soles accompanied by toenail damage for over 10 years; case 4, a 49-year-old male, manifested desquamation of both hands and feet accompanied by nail changes and mild pruritus for more than 10 years. Direct microscopic examination of fungi in the 4 cases showed elongated, branched, and septate hyphae, and the pathogen was identified as Neoscytalidium dimidiatum by fungal culture and DNA sequencing. A diagnosis of superficial neoscytalidiosis was made. The case 1 and case 2 were cured after treatment with topical antifungal agents, and the case 3 and case 4 were cured after combination therapy with topical and oral antifungal agents. This article indicated that Neoscytalidium dimidiatum-caused skin infections of the hands and feet mainly manifested as diffuse skin roughness, mild keratosis and thickening, dryness and desquamation of the palms and soles, which were similar to tinea pedis and tinea manuum; Neoscytalidium dimidiatum could also cause nail infections, with clinical manifestations similar to onychomycosis, mainly presenting as distal and lateral subungual onychomycosis.

Key words: Dermatomycoses, Neoscytalidium dimidiatum, Superficial neoscytalidiosis, Skin manifestutions, Onychomycosis, Therapy