[COVID-19 pandemic in a cohort of lung transplant recipients: Insights into immune system status].

OBJECTIVE

Lung transplant recipients represent a high-risk population for COVID-19, primarily due to long-term immunosuppressive therapy. The study aimed to describe the impact of COVID-19 in a cohort of lung transplant recipients during the pandemic and to identify selected risk factors associated with an unfavorable disease course.

MATERIAL AND

METHODS

This retrospective analysis included patients followed at a specialized post-transplant outpatient clinic of the Department of Respiratory Medicine, University Hospital Olomouc. All patients had undergone lung transplantation at the 3rd Department of Surgery, Motol University Hospital, and were followed within an inter-institutional collaborative care program. Data were obtained from the national infectious diseases information system (ISIN), outpatient and inpatient medical records, and were statistically analyzed with a focus on clinical and genetic risk factors.

RESULTS

A total of 87 patients (29 women, 58 men) were included in the study and followed from the beginning of the pandemic in 2020 through December 2023. COVID-19 was diagnosed in 65 patients (74.7%), while 22 patients (25.3%) remained uninfected. The overall mortality was 15.4% (10 patients), with the highest fatality rates observed during the early pandemic waves dominated by the original SARS-CoV-2 variants. Over time, the prognosis improved in association with the availability of vaccination, antiviral prophylaxis, and the emergence of the less pathogenic Omicron variant. Older age was identified as a significant risk factor for severe disease and mortality. Time since transplantation and the presence of a single native lung did not have a significant impact on disease severity. Genetic risk factors associated with severe COVID-19 included the polymorphisms rs16944G (IL1B), rs2069763A (IL2), and rs2076295*G (DSP).

CONCLUSIONS

COVID-19 had substantial clinical consequences in the evaluated cohort of lung transplant recipients, with an overall mortality of approximately 15%. Independent risk factors for an unfavorable course included older age and insufficient prophylaxis. Selected genetic polymorphisms may represent additional risk factors. These findings may contribute to improved risk stratification for viral infections and to a better understanding of immune status in lung transplant recipients.