Moesziomyces aphidis Bloodstream Infection in Oncologic Patient: First Report in Poland.

Moesziomyces spp. (Pseudozyma) is a genus recognized as a new opportunistic human pathogen, causing systemic infections including premature neonates and adult patients. These fungi's natural resistance to caspofungin enables them to spread through vascular catheter colonization, making them a new etiological agent associated with fungal bloodstream infections (FBIs) and a significant contributor to high mortality rates. In this report, we present a case of fungemia caused by Moesziomyces aphidis species in a patient with medical history that revealed pancreatic cancer infiltrating the duodenum and bile ducts. During hospitalization, the M. aphidis was cultured twice from peripheral blood samples on Sabouraud agar. The strain was sensitive to amphotericin B and voriconazole. In vitro susceptibility testing revealed resistance to fluconazole, caspofungin, anidulafungin, and micafungin. Antifungal therapy with voriconazole resulted in the resolution of clinical symptoms associated with fungal infection. Related to M. aphidis fungemia, we reviewed a total of three cases in Europe published in the PubMed database between 2003 and 2024. To the best of our knowledge, this is the first case of M. aphidis FBI in Poland and the fourth case in an adult patient in Europe.