Wahab, Abdul

Abstract Rationale Fungal infections remain a major cause of morbidity and mortality post lung transplant due to unique exposure of the allograft to the external environment and the intensity of immunosuppression. Single-center studies have described variable rates of fungal infections. Contemporary population-level data with temporal trends, pathogen distribution, and associated outcomes are limited. Leveraging a large multicenter real-world dataset, we aimed to characterize incidence, prevalence and clinical outcomes of fungal infections among adult lung-transplant recipients. Methods Data were obtained from the TriNetX Global Collaborative Network (160 HCOs). Adult lung-transplant recipients (≥18 years) were identified between 2005 and 2024, using ICD and CPT procedure codes. Patients with solid organ transplants other than lung, combined-organ transplant or stem-cell transplant and HIV patients were excluded. Patients with pre transplant fungal infections were also excluded. Pre-transplant characteristics included demographics, comorbidities within a year, laboratory values within seven days, and medication within 90 days before transplantation. Post-transplant fungal infections were identified using ICD-10 codes for Aspergillus, Candida, Cryptococcus, Mucorales, Histoplasma, Blastomyces, Coccidioides, and Pneumocystis. TriNetX platform was utilized for statistical analysis. Incidence and prevalence of infections, all-cause mortality and transplant rejection were analyzed. Results A total of 12,857 adult lung-transplant recipients were identified. The mean age at transplantation was 57.6 ± 13.4 years, with a male predominance of (57%) and majority were white (65%). Average BMI was 26.8 ± 5.7 kg/m². The most common pulmonary conditions were COPD (15%), pulmonary fibrosis (17%), pulmonary hypertension (9%), bronchiectasis (3%), and cystic fibrosis (3%). Pre-transplant fungal and viral screening assays were rarely available (<1%). Medication exposure within 90 days prior to transplant demonstrated prednisone prescription (17%) methylprednisolone (7%), tacrolimus (6%), and mycophenolate mofetil (7%). Azathioprine and basiliximab were used in 2% each. Systemic antifungals (voriconazole, posaconazole, or fluconazole) in approximately 1% each.The overall incidence of post-transplant fungal infection was 3 % across full study period, rising to 7% in the modern era (2015-2024). Most frequently identified pathogens were Candida spp. (4.8%) and Aspergillus spp. (2.9%), followed by Pneumocystis Jirovecii (0.5%). Infection rates increased from 22 per 1,000 (2005-2014) to 75 per 1,000 (2015-2024) suggestive of improved diagnostic sensitivity and data capture, and longer post-transplant survival. All-cause mortality 5-year post transplant was 22.1%, and rejection rate was 22.5%. Conclusion Our study highlights a rising burden of fungal infections among lung-transplant recipients with potential implications for early post-transplant surveillance and antifungal prophylaxis strategies. This abstract is funded by: None

Abstract Rationale Fungal infections are common after lung transplantation and may adversely affect graft function and survival, but long-term outcomes remain incompletely defined. Using a large multicenter real-world dataset, we aimed to study the impact of post-transplant fungal infections on clinical outcomes of lung transplant recipients. Methods We conducted a retrospective, cohort study using the TriNetX Global Collaborative Network, which aggregates de-identified electronic health records from >160 healthcare organizations across North America, Europe, and Asia. Adult lung transplant recipients (≥18 years) between 2005 and 2024 were identified using ICD-10 and CPT codes. Patients with post-transplant fungal infection (aspergillosis, candidiasis, mucormycosis, histoplasmosis, coccidioidomycosis, blastomycosis) and matched controls without fungal infection within one year before or any time after transplant were identified. The index date was the date of transplantation. Propensity-score matching was performed on demographics, comorbidities, laboratory values, procedures and immunosuppressive medications. Outcomes included all-cause mortality (primary), allograft rejection, and chronic lung allograft dysfunction (CLAD) at 6 months, 1 year, 3 years, and 5 years. Kaplan-Meier and Cox proportional hazards models were used to estimate risk ratios (RRs), hazard ratios (HRs), and 95% confidence intervals (CIs). Analyses were conducted in TriNetX Analytics (v25.0, Cambridge, MA). Results A total of 3,083 patients with post-transplant fungal infection and 11,625 patients without infection were identified. Mean age was 58 ± 13 years, and 56% were male. The most common pulmonary comorbidities were chronic obstructive pulmonary disease, unspecified pulmonary fibrosis, idiopathic pulmonary fibrosis and bronchiectasis. Immunosuppression exposure was similar across groups. After propensity score matching across 56 clinical variables, both groups (1,790 per group) were well balanced. Mortality was higher in the fungal infection cohort at all follow-up points: 13.% vs 9% at 6 months (RR 1.45, 95% CI 1.2-1.75, p = 0.001), 17.8% vs 13% at 1 year (RR 1.36, p = 0.0001), 27.7% vs 21% at 3 years (RR 1.28, p < 0.0001), and 33 % vs 25% at 5 years (RR 1.32, p < 0.0001). Allograft rejection remained consistently higher (46-61% vs 22-34%), while CLAD occurred two- to three-fold more frequently (1.8-5.7% vs 0.7-2%). Conclusion Post-transplant fungal infection is independently associated with significantly increased mortality, acute rejection, and CLAD following lung transplantation. These findings underscore the need for early fungal surveillance, optimized antifungal prophylaxis, and individualized immunosuppression strategies to improve long-term patient outcomes. This abstract is funded by: None