Impact of HLA Alleles on COVID-19 Severity in Kidney Transplant Recipients: A Single-Center Study.

Introduction The coronavirus disease 2019 (COVID-19) pandemic has significantly impacted global health, particularly affecting vulnerable populations, such as organ transplant recipients. Human leukocyte antigens (HLAs) play a critical role in immune response regulation, and understanding their association with COVID-19 can provide insights into disease susceptibility and severity. This study aims to explore the association between HLA allele variability and COVID-19 susceptibility and severity among kidney transplant recipients. Methods In 2023, we conducted a study on 73 kidney transplant recipients who tested positive for COVID-19 via polymerase chain reaction. This study included assessments of clinical status, immunosuppressive drug levels, HLA allele frequencies, and donor-recipient tissue compatibility. Molecular analyses were performed using sequence-specific oligonucleotide typing, and statistical analysis was conducted using IBM SPSS Statistics, version 20.0 (IBM Corp., Armonk, NY). Results Among the participants, 31 were hospitalized and 42 were treated as outpatients. Significant differences were observed in HLA allele distributions, particularly the HLA-A*11 allele, which was more prevalent in outpatient-treated patients, suggesting a potential protective effect. No significant age differences were observed between hospitalized and outpatient groups. Serum tacrolimus levels were notably higher in outpatients. Statistical analyses revealed significant associations between certain HLA groups and the severity of COVID-19 infection. Conclusions This study highlights the importance of HLA allele compatibility in influencing the clinical outcomes of COVID-19 in kidney transplant recipients. The findings suggest that specific HLA alleles may reduce susceptibility or moderate the severity of COVID-19, indicating a need for broader genetic studies across diverse populations to validate these observations and improve management strategies for transplant recipients during pandemics.