Raising a Brown Flag: An Unusual Presentation of Aspergillus Peritonitis

Introduction: Fungal peritonitis is a rare complication of peritoneal dialysis (PD), but one with high rates of mortality and technique failure. Candida species represent most causative organisms of fungal peritonitis while infection with Aspergillus is less common but associated with higher mortality. We present a rare case of asymptomatic Aspergillus peritonitis identified due to discoloration in the PD catheter transfer set. Case Description: A 71-year-old male with a history of liver transplant, diabetes, and end-stage kidney disease due to calcineurin inhibitor toxicity presented for his routine PD clinic visit. An area of brown discoloration was seen in the proximal portion of his catheter transfer set (see Picture 1). He noted the color change over 3 days prior without associated abdominal pain or fever. The transfer set was exchanged and sent to anatomical pathology to evaluate the cause of the brown discoloration. PD fluid was sent for cell count and culture. White cell count was elevated: 432 cell/mcL with 54% neutrophils and 11% eosinophils. Intraperitoneal vancomycin and ceftazidime were started for empiric peritonitis treatment. Last peritonitis episode was 7 months before and he had no recent antibiotic exposure. The pathologist’s evaluation of the transfer set revealed septate, acute angle branching hyphal elements consistent with mold. The patient was admitted to the hospital, treated with oral voriconzole, and underwent urgent PD catheter removal with transition to hemodialysis. Peritoneal catheter tip culture was positive for Aspergillus species. Discussion: Aspergillus peritonitis is a rare complication of PD. Even in the absence of classic peritonitis symptoms, brown discoloration in the PD catheter warrants evaluation for potential fungal infection. Early recognition and intervention, with prompt PD catheter removal, are crucial due to associated high mortality and morbidity.Picture 1: Bisected transfer set with brown discoloration