Candida nivariensis, an emerging fungus causing peritonitis in a patient receiving peritoneal dialysis

Timely diagnosis and management of Quambalaria cyanescens-induced peritoneal dialysis peritonitis: A rare case highlighting the role of galactomannan testing

Fungal peritonitis in peritoneal dialysis (PD) presents significant challenges. We report the second Quambalaria cyanescens-related PD peritonitis in a 53-year-old male. Negative bacterial cultures and a positive galactomannan (GM) index in both PD effluent (PDE) (0.65) and serum (0.98) prompted early PD catheter removal on day 5. Molecular sequencing confirmed Q. cyanescens, with antifungal susceptibility testing revealing resistance to azoles and echinocandins but susceptibility to amphotericin B and isavuconazonium. Treatment with amphotericin B and voriconazole resolved symptoms, with no relapses during a two-year follow-up. This case highlights GM testing's critical role in guiding catheter removal and adherence to the 2022 ISPD Peritonitis Guidelines, ensuring favorable outcomes for rare fungal PD infections.

Three cases of vulvovaginal candidiasis due to Candida nivariensis

Candida nivariensis is emerging as a highly resistant species of the Candida glabrata complex causing invasive and mucocutaneous infections. In this study, three cases of vulvovaginal candidiasis caused by C. nivariensis are described and identified by Internal Transcribed Spacer 1-2 sequencing. All isolates were susceptible in vitro to anidulafungin, micafungin, caspofungin, 5-flucytosine, posaconazole, voriconazole, itraconazole, amphotericin B, and showed dose-dependent susceptibility to fluconazole. In two patients, three doses of oral fluconazole were effective, while one patient developed clinical fluconazole resistance with a new relapse after 6 months. Increasing the weekly dose of fluconazole showed to be effective in this patient.

Peritoneal dialysis-associated peritonitis from pauci-septated mold: Life-threatening but curable

Two cases of PD-associated peritonitis due to Cunninghamella (C. bertholletiae and C. guizhouensis) were reported here with favorable outcomes, albeit presenting with septicemia. Both patients presented with classic features of bacterial peritonitis, cloudy effluent with a neutrophil predominance, followed by fever and septicemia/septic shock. The pathogen species were confirmed and verified by molecular phylogeny using universal and specific fungal primers. All isolations were susceptible/intermediately susceptible to amphotericin B but resistant to other antifungal agents, including triazoles, caspofungin, and terbinafine. Both cases were successfully treated with timely PD catheter removal and antifungal medications for 2-4 weeks.