Cryptococcus laurentii Bloodstream Infection in an Immunocompetent Adult: A Rare Central Line-Associated Infection...

Cryptococcus laurentii (Papiliotrema laurentii) is a rare opportunistic yeast traditionally considered non-pathogenic in humans. We present a case of a 54-year-old immunocompetent male with a history of osteomyelitis and an indwelling peripherally inserted central catheter (PICC) who developed bloodstream infection with extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae, followed by catheter-associated fungemia with C. laurentii. The patient had no history of diabetes mellitus, malignancy, organ transplantation, or immunosuppressive therapy, and HIV testing was negative. He had been receiving intravenous vancomycin at a rehabilitation facility and admitted to tampering with his catheter, including showering without protection. Upon hospital transfer, empiric therapy with piperacillin-tazobactam and vancomycin was initiated. Blood cultures grew ESBL-producing K. pneumoniae, prompting a switch to meropenem. Transthoracic echocardiography showed no vegetations. Subsequent blood cultures grew C. laurentii. The PICC line was removed upon confirmation of fungal growth. Lumbar puncture revealed clear cerebrospinal fluid with normal cell counts, glucose, protein, and negative cultures, excluding central nervous system involvement. Fluconazole 400 mg daily was initiated intravenously and transitioned to oral therapy. The patient completed a total of two weeks of fluconazole and meropenem, with documented blood-culture clearance prior to discharge. This case highlights the emerging pathogenicity of C. laurentii in immunocompetent hosts with indwelling catheters and emphasizes the importance of catheter hygiene and early fungal identification in catheter-associated bloodstream infections.