Background pandemic SARS-CoV-2 is still ongoing. In this context, patients after organ transplantation are especially endangered due to their increased susceptibility to infections. Real effectiveness of vaccinations against SARS-CoV-2 and exposition to the virus in population after organ recipients is still being assessed. Methods We investigated 371 adult pts (17.3% women), aged 54 ±14 years, median time from transplantation 1296, IQR: 473-400 days after orthotopic heart transplantation consecutively admitted to Transplant Centre in the timeframe between February and September 2021. SARS-CoV-2 spike protein antibodies were assessed quantitatively by Elecsys® Anti SARS -CoV-2 S, Cobas – Roche. Data according past COVID-19 infection and vaccination were compared with the test results. Among the whole group, 59 pts were unvaccinated and had no past COVID-19 infection, full course of vaccination (two doses) with mRNA vaccine had 200pts, one patient received viral vector vaccine, after single dose of two-doses vaccine were 11 pts, after the infection were 99 pts. Median time from vaccination to antibodies’ assessment was 54 days, IQR: 30-76 days. Aim Determination of exposure to the virus among patients after HTx before the vaccination and humoral response to the vaccination. Assessment of the role of anti-spike antibodies in the prevention of infection. Results After vaccination 22.3% (45 pts) had no antibodies, 47.3% (95 pts) had titer between 0.8 U/ml (0.82 BAU/ml) and 250 U/ml (257.25 BAU/ml), 30.2% (61 pts) had titer above 250 U/ml (257.25 BAU/ml). After single dose of two-doses vaccine 63% pts had no antibodies. In the group of unvaccinated patients, 3 pts (5.1%) had the titer above 250 U/ml (257.25 BAU/ml), 12 pts (20.3%) had the titer up to 250 U/ml (257.25 BAU/ml). In the patients after COVID-19 only 2% did not show anti-spike antibodies, in 61.4% their titer was above 250 U/ml (257.25 BAU/ml). In the group of patients infected after the full course of vaccination (4 pts after single dose of two dose vaccine, 2 after two doses), none of the patients developed antibodies after the vaccination. Up to end of September 2021, none of the patients with antibodies against SARS-CoV-2 developed COVID-19. Conclusion we suppose, that presence of spike protein antibodies may be relevant marker of effective vaccination. In the HTx group exposition to SARS-CoV-2 is high.
Serologic status according SARS-CoV-2 in patients after orthotopic heart transplantation (HTx)