Humoral Response To SARS-CoV-2 Is Well-Preserved And Symptom-Dependent In Kidney Transplant Recipients.

Magicova, Maria; Fialova, Martina; Zahradka, Ivan; Rajnochova-Bloudickova, Silvie; Hackajlo, David; Raska, Petr; Striz, Ilja; Viklicky, Ondrej

Data on immune response to SARS-CoV-2 in kidney transplant recipients are scarce. Thus, we conducted a single-center observational study to assess the anti-SARS-CoV-2 IgG seroprevalence in outpatient kidney transplant recipients (KTR; n=1037) and healthcare workers (HCW; n=512) during the second wave of covid-19 pandemic in fall 2020 and evaluated the clinical variables affecting antibody levels. Antibodies against S1 and S2 subunit of SARS-CoV-2 were evaluated using immunochemiluminescent assay (cut off 9.5 AU/mL, sensitivity of 91.2% and specificity of 90.2%). Anti-SARS-CoV-2 IgG seroprevalence was lower in KTR than in HCW (7% vs. 11.9%, p=0.001). Kidney transplant recipients with SARS-CoV-2 infection were younger (p=0.001) and received CNI-based immunosuppression more frequently (p=0.029) than seronegative KTR. Anti-SARS-CoV-2 IgG positive symptomatic KTR had higher BMI (p=0.04) than asymptomatic KTR. Interestingly, anti-SARS-CoV-2 IgG levels were higher in KTR than in HCW (median 31 AU/ml, IQR 17-84 vs. median 15 AU/ml, IQR 11-39, p<0.001). The presence of moderate to severe symptoms in KTR was found to be the only independent factor affecting IgG levels (beta 37.36, 95% CI 19.9-54.8, p<0.001) in multivariable model. In conclusion, KTR exhibit a well-preserved symptom-dependent humoral response to SARS-CoV-2 infection.