Subcutaneous infection by Ochroconis mirabilis in an immunocompetent patient

Abstract

Recently, the taxonomy of Ochroconis (Ascomycota, Pezizomycotina, Venturiales, Sympoventuriaceae) has been revised with the recognition of an additional genus, Verruconis. Ochroconis comprises mesophilic saprobes that occasionally infect vertebrates which mostly are cold-blooded, while Verruconis contains thermophilic species which is a neurotrope in humans and birds. On the basis of molecular data it is noted that only a single Ochroconis species regularly infects immunocompetent human hosts. Here we report a subcutaneous infection due to Ochroconis mirabilis in a 50-year-old immunocompetent female patient. In vitro antifungal susceptibility tests revealed that terbinafine was the most effective drug. The patient was successfully cured with oral administration of terbinafine 250 mg daily in combination with 3 times of topical ALA-photodynamic therapy for 9 months.

Keywords: Cutaneous infection; Ochroconis; Ochroconis musae; Terbinafine.

Fig. 1

(A) Erythematous, nodular lesions in the face. (B) Skin lesions markedly recovered after 3 months of oral administration of terbinafine combined with 3 times of topical ALA-photodynamic therapy. (For interpretation of the references to color in this figure, the reader is referred to the web version of this article.)

Fig. 2

(A) Dematiaceous fungi in PAS stained slides. Hypha and yeast cells appear PAS positive. The fungal forms are within giant cells.(PAS stain, original magnificent, 400×). (B)Direct examination of 10% potassium hydroxide wet mounts of the scales of the lesions revealed abundant light-brown, branched and septatehyphae(original magnificent, 400×). (C and D) On Sabouraud dextrose agar, colonies of Ochroconis musae are smooth, dry, flat, and dark brown to-brown on the surface and reverse, and produce a characteristic red pigment. (D and F) Lactophenol cotton blue (LPCB) stain shows slender, pointed conidiophores with one or two clavate, conidia at the tip of the denticles. Conidia are two-celled, smooth-walled, subhyaline, and cylindrical (E original magnificent, 400×). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Fig. 3

Neighbor-joining analysis with 1000 boostraps of ITS sequences from Ochroconis reference strains and patient's isolate.