Rare Mould Fungaemia at a Tertiary Academic Hospital in Athens, Greece: A 15-Year Survey and Literature Review

Invasive infections caused by rare moulds (RM) are increasingly reported and often exhibit resistance to antifungal agents. Their epidemiology varies regionally, yet data from Greece are scarce. To address this gap, we conducted a 15-year retrospective study of RM fungaemia at a tertiary academic hospital in Athens, Greece. All microbiologically confirmed cases in hospitalised patients between 2010 and 2024 were reviewed. Demographic and clinical data were retrieved from medical records. Incidence rates were calculated per 1000 admissions and 10,000 bed-days. Isolates were morphologically identified and, when available, molecularly characterised and tested for antifungal susceptibility according to EUCAST guidelines. Eight RM fungaemia episodes (0.8% of total fungaemias) were identified, with an incidence of 0.01/1000 admissions and 0.03/10,000 bed-days, without bacterial co-infections. Haematological malignancies (62%) were the most common underlying condition. <i>Fusarium</i> spp. were the predominant pathogens (6/8), followed by single cases due to <i>Lomentospora prolificans</i> and <i>Acremonium</i> spp. Amphotericin B showed the highest in vitro activity against <i>Fusarium</i> isolates (MIC 0.5-1 mg/L), followed by voriconazole (MICs 2-8 mg/L) whereas other azoles showed no in vitro activity (MICs ≥ 8 mg/L). Half of the infections were breakthrough, whereas in 3/8 cases, the diagnosis was established post-mortem (n = 2) or post-discharge. Among the five patients who received treatment, the crude mortality rate was 60%. This first epidemiological report on RM fungaemia in Greece highlights the predominance of <i>Fusarium</i> spp., the frequency of breakthrough infections, and the challenges in early diagnosis and management. Increased clinical awareness and regional surveillance are essential for optimising outcomes.