IMPACT OF ACUTE REJECTION ON LONG-TERM PATIENT SURVIVAL & GRAFT OUTCOME IN KIDNEY TRANSPLANT RECIPIENTS IN A TERTIARY CARE CENTRE IN SOUTH INDIA

Introduction:

Renal transplantation is the best modality of renal replacement therapy as it increases longevity and improves the quality of life in patients with End Stage Renal Disease.  An episode of acute rejection increases the risk for late allograft failure and not all acute rejection episodes lead to chronic allograft failure. Timing of rejection, severity of rejection episodes, and response to therapy are known to affect long-term graft function. The present study was an attempt to determine the impact of the timing of acute rejection episodes on long-term patient survival and graft outcome among kidney transplant recipients.  

Methods:

A retrospective study was performed involving 201 cases of renal transplantation with biopsy-proven rejections from January 2015 to December 2018 in the Institute of Nephrology, Madras Medical College, Chennai, Tamil Nadu, India. Age less than eighteen years, patients with multiple organ transplants, repeated renal transplantation, primary nonfunctioning transplants and graft loss or death to surgical causes were excluded from this study. The risk factors such as age, gender, hepatitis C status, dialysis vintage, history of blood transfusion, type of transplant, usage of induction agents, graft function, and follow-up period, presence of acute rejection and management, serum creatinine levels, and eGFR were recorded. We analyzed the impact of timing of rejection (Early and late) on long-term patient outcome & death censored graft outcome when compared to patients with no rejection. We describe the total incidence of acute rejection and classify the patients into three groups; No Acute Rejection (No AR), Early Acute Rejection (EAR), and Late Acute Rejection (LAR). EAR & LAR are defined as acute rejection before and after 6 months respectively. The clinical characteristics of the three groups were compared using the Chi-Square test or Exact Fisher t-test for categorical variables and the ANOVA test for continuous variables. The recipient’s age/sex, donor’s age/sex, Hepatitis C status, Dialysis vintage, Blood transfusion, and delayed graft function were used as independent variables in risk factor analysis. Treatment response, overall graft survival and patient survival were used as independent variables in outcome analysis. The proportions of early acute rejection and late acute rejection were determined and 1,3 and 5 years of patient survival and death-censored graft survival rate were analyzed using Kaplan Meier curves and Cox regression analysis. 

Results:

Among 201 cases, 48 cases (23.88%) had biopsy-proven AR (Early AR = 66.66%, late AR = 33.34%). The five-year patient survival rate was 96.7%, 87.5%, and 81.3% among No AR, early AR, and late AR cases. The five-year graft survival rate was 92.2%, 87.5%, and 68.8% respectively among no AR, Early AR, and Late AR cases. Immediate graft function and donor age of less than thirty years were found to be protective factors for No rejection cases. The mean patient survival time for Early acute rejection and Late AR was 4.75 years (95% CI 4.363 – 5.137) and 4.667 years (95% CI 4.150 – 5.183) respectively after five years of the follow-up period. The mean graft survival time for Early acute rejection and Late AR was 4.798 (95% CI 4.475 – 5.120) and 4.438 years (95% CI 3.759 – 5.116) respectively. The Cox regression model shows a hazard ratio of 6.6 in recipient age with patient mortality.   

Conclusions:

Acute rejection episodes regardless of their timing, significantly worsened graft and paient survival. Late acute rejection had a high impact on graft failure and had a detrimental effect on long-term graft survival whereas early acute rejection had a better prognosis when compared to late acute rejection. 

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.