Invasive Fungal Infections in Heart Transplants: A 10‐Year, Single Centre Retrospective Cohort Study From Subtropical Australia

BACKGROUND: Invasive fungal infections (IFIs) are a major cause of morbidity and mortality in solid organ transplant recipients. However, their epidemiology in Australian heart transplant cohorts remains poorly defined. We aimed to determine the incidence, microbiological profile, diagnostic performance, and survival outcomes associated with IFIs in heart transplant recipients. METHODS: We conducted a retrospective cohort study of all heart transplant patients who were diagnosed with an IFI between January 1, 2014 and February 29, 2024 at a single center in Queensland, Australia. Patient characteristics, details of transplant hospitalization, antifungal prophylaxis, microbiology, and treatment of fungal infections were described. RESULTS: Of 73 patients with suspected IFI, 48 met criteria for possible 19% (n = 9), probable 27% (n = 13), or proven 54% (n = 26) infection. Aspergillus 33% (n = 16), Candida 17% (n = 8), Scedosporium 13% (n = 6), and polymicrobial infections 8% (n = 4) were most common. Median time to IFI diagnosis was 7 months post-transplant. Of 148 patients who received heart transplants at the center between January 2014 and February 2024, 32 developed IFI; estimated incidence was 49 (95% CI: 35-70) per 1000 person years. Among those who died (n = 21), median time from transplant to death was 5.75 years. Baseline Charlson comorbidity index was the only variable significantly associated with all-cause mortality (p = 0.041). CONCLUSION: IFIs in heart transplant recipients frequently occur beyond the first year posttransplant. Higher Charlson scores were associated with reduced survival. These findings support the need for tailored prophylaxis strategies and improved diagnostic algorithms in preventing posttransplant IFI.