Background: End stage renal disease (ESRD) patients receiving RRT ( renal replacement therapy) either in the form of dialysis or renal transplant (RTx) have been identified as a high-risk group who are at increased risk of morbidity and mortality from Severe Acute Respiratory Syndrome Corona Virus 2 (SARS Cov-2) or COVID-19infection  Also there are mixed reports on vaccine response against COVID-19 in RRT subjects.Hence, this study was conducted to observe the immune response after two doses of vaccine against COVID-19 in a resource poor situation among a group of RTx recipients.
Methods: Data in this study is presented from 2 transplant centres starting in early part of 2022. Most of the RTX patients were from non-profit hospitals. Total 73 renal transplant recipients were included in this study. Detail information regarding COVID-19 infection, based on WHO criterion, recovery and vaccination was carried out in each patient. Relevant laboratory investigations was done. A quantitative measurement of IgG antibody against (S) protein of SARS-Cov-2 was done by CMIA developed by Abbott. A cut-off value ≥50 AIU/L of IgG against spike protein is considered a positive response.
Results: The mean age was 35±8 years; CKD duration 10±3 years; pretransplant dialysis duration 12±8 months; BMI 24±4 kg/m2; hemoglobin 13±2 g/dl;albumin 3.2±0.4 g/dl and IgG antibody against (S) protein, irrespective of vaccination status, was 2836±4227 AIU/L. The proportion of vaccinated subjects were   32%. A positive immune response in vaccinated   RTx subjects was 100%. On the other hand, a positive titer was also present in non-vaccinated subjects at a proportion of 94%. Comparisons of vaccinated vs. non-vaccinated showed no differences in age 35±8 &34±8  years; RTX duration 15±14 & 18±25 years; BMI 25±4 & 24±4  kg/m2; hemoglobin 13±2 & 13±1 g/dl; creatinine 1.3±0.9 & 1.3±0.9 mg/dl and IgG antibody against (S) protein as 4818±85337 & 3122±6713AIU/L; (p=NS).  The binary regression for immune response was not associated with any recorded clinical or laboratory parameters.
Conclusion: In this study a positive immune response with high titre was seen in all most all transplant subjects after two dose vaccination against CODID-19. At the same time the non-vaccinated subjects also showed a positive titre in nearly 95% indicating acquired passive immunity in them. Renal transplant patients were most likely exposed to high infection environment evident from a raised titer in all. The similar renal function in both groups could be related to the strong anti-covid titter prevailing in them.