Recalcitrant Primary Subcutaneous Phaeohyphomycosis Due to Phialophora verrucosa

Abstract

Phialophora verrucosa has rarely been reported for causing phaeohyphomycosis, which tends to occur in immunocompromised individuals. The case of primary subcutaneous phaeohyphomycosis due to P. verrucosa in an otherwise healthy Chinese female is presented. The girl presented with asymptomatic skin lesions when she was only 16 year old. Histological examinations revealed multiple dematiceous hyphael elements in the dermis and subcutaneous tissues. Fungal cultures were identified as P. verrucosa repeatedly based on the morphological features and confirmed by the internal transcribed spacer region nucleotide sequencing. The infection was so extremely recalcitrant that prolonged systemic antifungal regimens for 12 years revealed limited effect. The skin lesions slowly progressed and caused marked disfigurement despite the encouraging results of in vitro susceptibility. However, no relevant side effects have been reported in the course, and the patient gave birth to a healthy baby while under the maintenance treatment of itraconazole and terbinafine. This case is special in terms of the early onset, the rare clinical aspect of the pathogen, the discrepancy between in vitro and in vivo antifungal activities and especially the prolonged and recalcitrant course in such an otherwise healthy host.

Black Molds and Melanized Yeasts Pathogenic to Humans

“…Infections by P. verrucosa can be destructive and refractory to therapy (Saunte et al 2011). Other species, such as Phialophora europaea are colonizers of human skin and nail without causing major symptoms (Gao et al 2013). The natural habitat of most species is unknown, although some are regularly found in bathing facilities and similar humid, nutritionally poor environments.…”

1,10-Phenanthroline-5,6-Dione–Based Compounds Are Effective in Disturbing Crucial Physiological Events of Phialophora verrucosa

“…Due to the chronic nature and the well-known multidrug-resistance profile, it is very difficult to treat patients with CBM using currently available therapies (Queiroz-Telles and Santos, 2012 ). Prolonged treatment and disease relapsed are huge concerns, and antifungal therapies especially for Phialophora infections have generally been disappointing (Gao et al, 2013 ). For these reasons, new antifungal agents should be studied in order to find out alternative therapeutic ways to treat CBM and other infections caused by P. verrucosa .…”

In Vitro Activities of Nine Antifungal Drugs and Their Combinations against Phialophora verrucosa

“…With the chronic repetitious nature of the infections, traditional drugs and physical therapies cannot deal with the relapse, resistance, and incomplete cures of chromoblastomycosis and phaeohyphomycosis (1). Currently, clinical P. verrucosa infection cases and antifungal therapies, including drug combination therapies, have been reported (2,(4)(5)(6)(7)(8)(9)(10), but effective therapies are still limited. Previous studies have indicated that terbinafine combined with itraconazole, amphotericin B, or voriconazole showed synergy against dematiaceous molds such as Fonsecaea pedrosoi and Exophiala jeanselmei (11); amphotericin B combined with terbinafine also showed synergy for six P. verrucosa isolates (12).…”