Serologic Evaluation for Severe Acute Respiratory Syndrome Coronavirus 2 in Pediatric Heart Transplantation Recipients and Patients on a Pediatric Heart Transplantation Waiting List in a Quaternary Hospital.

Background: The Coronavirus disease 2019 (COVID-19) pandemic has been a global reality for longer than 3 years. Serologic studies have great importance for understanding the virus's behavior in populations, as it can suggest the status of the epidemic in a community. This cross-sectional study aimed to analyze the serologic profile for COVID-19 in patients before and after pediatric heart transplantation.

Methods: Serology data on IgG and IgM antibodies for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were collected in patients of the Pediatric Cardiology and Congenital Heart Diseases unit of a Brazilian hospital between January and August 2022. A total of 174 patients were recruited, including 28 on the transplantation waiting list and 146 heart transplant recipients. Information for each patient, including demographics (age, sex, state of origin), type of heart disease (congenital or acquired), and time after transplantation, was analyzed.

Results: Overall, 72 patients had a positive serology for anti-N antibodies (48.0%), including 62 heart transplant recipients and 10 patients on the transplantation waiting list, The positivity rates in these 2 groups were 48.1% and 47.6%, respectively. Positivity rates for previously infected individuals were 62.5% and 62.1%, respectively.

Conclusions: Approximately one-half of our study sample had IgM or IgG antibodies against the SARS-CoV-2 virus. Serologic studies on the duration and level of protection provided by these antibodies are relevant public health tools for health promotion of vulnerable groups and can be useful for future studies on antibody behavior.