When "Candida ciferrii" Isn't Candida: Sequencing reveals multidrug-resistant Blastobotrys adeninivorans PD peritonitis.

Fungal peritonitis is a severe complication of peritoneal dialysis (PD), increasingly involving rare yeasts that challenge routine diagnostics. We report PD-associated peritonitis caused by Blastobotrys adeninivorans, initially misidentified as Candida ciferrii by automated platforms (VITEK 2 and MALDI-TOF MS). Persistent neutrophilic inflammation and elevated effluent β-D-glucan prompted multilocus sequencing, which confirmed B. adeninivorans. Susceptibility testing showed markedly elevated MICs to amphotericin B, azoles, and echinocandins, interpreted cautiously because validated breakpoints are unavailable. This case illustrates how persistent culture-positive PD peritonitis with discordant or unusual yeast identification should prompt molecular confirmation. Clinical resolution followed PD catheter removal and transition to haemodialysis, underscoring the importance of early source control in refractory PD-associated fungal peritonitis.