Subcutaneous phaeohyphomycosis caused by Hongkongmyces snookiorum in a kidney transplant patient: a case report

BACKGROUND: Morbidity and mortality in transplant patients is increased by infection caused mainly by rare opportunistic pathogens. The present study reports a case where Hongkongmyces snookiorum caused subcutaneous phaeohyphomycosis in a kidney transplant patient. CASE PRESENTATION: A 47-year old Chinese woman with chronic kidney disease 5 underwent kidney transplantation 3 years ago. Her regular medications included Tacrolimus (1 mg, two times daily), Mycophenolate Mofetil (two times 250 mg, twice daily) and Prednisone acetate tablets (5 mg daily). Eighteen months ago, her proximal right index finger was red, painful and swollen. After admission, a hard and fluctuating 1 cm × 1 cm abscess was found on the dorsal side of the right index finger. Gram and fluorescence staining of a direct smear of a syringe extraction from the abscess revealed presence of filamentous fungi. White velvet colonies (2–3 mm) were found on blood plate and Sabouraud glucose agar (SGA) after 1 week, and grey aerial hyphae were observed. After 15 days, a 26 mm gray colony was also observed on SGA. The homology between this filamentous fungus and Hongkongmyces snookiorum ILLS00125755 (Genbank Sequence ID: MH161189.1) was 99.66%. An in vitro antifungal susceptibility test showed that this filamentous fungus was sensitive to azoles such as itraconazole and voriconazole. CONCLUSIONS: We report an opportunistic fungus infection caused by Hongkongmyces snookiorum in a transplant patient. Our finding shows that prevention of subcutaneous fungal infection is necessary for kidney transplantation patients.