Mycosis of the Plantar Surface of Foot Owing to Nondermatophyte Mold Nodulisporium griseobrunneum Mimicking a Tinea Pedis

Nondermatophyte molds (NDM) and dematiaceous molds are less frequently implicated as the etiological agents of tinea-like infections of the foot. Among the etiological agents, Hendersonula toruloidea (now, Nattrassia mangiferae), Scytalidium hyalinum, Alternaria species (spp.), and Fusarium spp. are infrequently associated with foot mycoses. Nodulisporium (N.) spp. is a mitosporic NDM, which has been implicated in human infections like cerebral phaeohyphomycosis and allergic fungal sinusitis. Here, we report N. griseobrunneum in a 9-year-old female with mycosis of the plantar surface of foot mimicking a tinea pedis. Potassium hydroxide mount of skin specimen demonstrated dichotomous branching septate hyphae. Fungal culture and molecular sequencing established N. griseobrunneum as the etiological agent. Antifungal susceptibility testing revealed lower MICs to all seven drugs tested including itraconazole (ITR). The patient was treated with ITR and topical terbinafine. To the best of our knowledge, this is the first communication depicting molecular confirmation of the etiologic agent and antifungal susceptibility data of the mycosis of the plantar surface of foot owing to N. griseobrunneum from India.

Keywords: Anamorph; Antifungal susceptibility; Hypoxylon griseobrunneum; ITS sequencing; Nodulisporium; Plantar dermatoses; Tinea-like.