Impacto da vacinação ou infecção por Covid-19 no painel de reatividade de anticorpos em pacientes com doença renal crônica na lista de espera para transplante

Abstract

Introduction: During the COVID-19 pandemic in Brazil, patients with chronic kidney disease (CKD) on dialysis were prioritized for vaccination. Previous studies, such as those in the H1N1 influenza pandemic, showed that vaccination of kidney transplant patients was associated with the emergence of anti-HLA antibodies. Objective: To investigate the occurrence of changes in the reactivity pattern of anti-HLA antibodies in chronic kidney patients enrolled in the national transplant list who were affected by COVID-19 and/or immunized. Method: This retrospective cohort study included 77 patients with CKD on hemodialysis, enrolled in the transplant waiting list allocated at CNCDO-OESTE and registered in the database of the Immunology and Transplant Laboratory of Uberlândia comparing the panel of antibody reactivity (PRA) before and after contact with SARS-CoV- 2 (infection) or with the antigen (immunization). The LABScreen MIXED assay was used as screening, considering a Mean Fluorescence Intensity (MFI)>300 positive. LABScreen SINGLE Antigen HLA Class I and SINGLE Antigen HLA Class II assays identified specificities of anti-HLA IgG antibodies in positive cases. Results: There was no significant difference in cPRA values between time points (pre: 0.00 (0.00 - 43.01); post: 0.00 (0.00 - 46.36); p=0.657). However, there was a significant increase in the percentage of positive cPRA cases at the time after infection and/or immunization (pre: 32 positive cases (41.6%); post: 34 positive cases (44.2%); p<0.001). Sixteen patients (20.8%) showed an increase in the final cPRA value, with two specific cases showing a significant change (increase of 52% and 79% at the time post-Covid-19). There was a change from negative to positive in 6 cases (7.8%). Eighteen patients (23.4%) showed a reduction in cPRA. In six specific cases, a reduction of 20% to 56% in the cPRA value was observed at the time post-Covid-19. Of the eight patients who showed significant changes, both an increase and a decrease in cPRA, three had previous infection with SARS-CoV-2 and five were immunized with the AZD1222 vaccine (Oxford/AstraZeneca), in addition to not presenting other sensitizing events. Furthermore, in this group of 8 patients, gender was not an important characteristic for these changes. Forty-three patients (55.8%) maintained the cPRA values. Conclusion: Although some changes in the antibody profile were observed after contact with SARS-CoV-2, these changes do not contraindicate vaccination in chronic kidney patients who are candidates for transplantation, reinforcing the importance of immunization in this risk group.