Persistence of antibody response to SARS-CoV-2 in a cohort of haemodialysis patients with COVID-19

Abstract

Background Haemodialysis patients are extremely vulnerable to COVID-19. Their immune response after infection is unclear. We have found high seroconversion rates in this population with 95% developing antibodies. It is unclear if and how long these antibodies persist. Here we investigate this with serial antibody testing. Methods We identified haemodialysis patients who had confirmed SARS-CoV-2 between March-May 2020 and measured monthly antibodies (IgG/IgM) in those who survived. We used a semi-quantitative cut-off index (COI) to create a qualitative result and plotted optical density (OD) over time. We used linear regression to examine the slope, as well as noting peak OD and time to peak OD. We correlated these against baseline demographics, markers of illness severity, and comorbidities. Results 122 patients were analysed. All remained antibody positive during follow-up; for a minimum of 148 days. 71% had a positive gradient indicating increasing antibody positivity over time. We found that age (p = 0.01), duration of PCR positivity (p = 0.06) and presence of symptoms (p = 0.05) were associated with a longer time to peak OD. Immunosuppression did not alter peak OD but did lead to a non-significant increase in time to peak OD and more patients had a subsequent fall in Ab levels (p = 0.02). Diabetic patients were more likely to have a positive slope (OR 2.26). Conclusions These results indicate that haemodialysis patients have a robust and sustained antibody response after confirmed COVID-19 infection with no suggestion that immunosuppression weakens this response. Although unclear what protection these antibodies confer, this encouraging that haemodialysis patients should respond to vaccination.

Serological Response to the BNT162b2 COVID-19 mRNA Vaccine in Adolescent and Young Adult Kidney Transplant Recipients

“… 26 , 27 Immunosuppressive treatment was shown to not influence the seroconversion rate over time, though it did lead to a slower rise in antibody levels and longer median time to peak antibody levels. 26 , 27 …”

Comparing Humoral and Cellular Adaptive Immunity during Convalescent Phase of COVID-19 in Hemodialysis Patients and Kidney Transplant Recipients

“…Further small studies also reported a 100% seroconversion rate in HD patients after COVID-19 [ 15 , 16 , 17 ]. Forbes et al published that 95% of hemodialysis patients mount an antibody response following COVID-19 [ 18 ]. No significant decline of antibody level over 145 days of observation was reported in that hemodialysis population.…”

Safety and Effectiveness of COVID-19 SPUTNIK V Vaccine in Dialysis Patients

“…The presence of SARS-Cov-2 infection was not associated with a higher frequency of ESAVI. Recent studies show that the majority of patients with COVID-19 prior to vaccination develop robust and durable immune responses at 6 months, with less than 5% no evidence of humoral and cellular immunity (29,30). However, preliminary studies carried out with another type of vaccine showed that in the case of those immunized without previous infection, there was a drop in antibody levels at six months, considering the need for a third dose (31,32).…”