IMPACT OF ONE-YEAR SERUM CREATININE ON LONG -TERM RENAL GRAFT SURVIVAL IN RENAL TRANSPLANT RECIPIENTS: SINGLE CENTRE STUDY

Introduction:

Renal transplantation is widely recognized as the optimal treatment for patients with end-stage renal disease (ESRD). Despite advances in short-term graft survival and reduced rejection rates, long-term graft survival still remains a challenge. Serum creatinine at the end of the first year appears to be an ideal time point as the graft has stabilized after events of drug toxicity, rejections, and infections. This study analyses the key factors influencing long-term graft outcomes, highlighting first-year serum creatinine as an indicator of long-term graft survival

Methods:

This single-Center retrospective cohort study involved patients who underwent renal transplants at our Center. Among 424 patients transplanted from 2009 to 2019, 201 patients who were in regular follow-up for at least 5 years were included. Patients lost to follow-up were excluded. Of the screened patients, 25 had graft loss within the first year (22 deaths, 3 graft nephrectomies). The remaining 176 patients were stratified into four cohorts based on first-year serum creatinine values: G1: <1 mg/dL; G2: 1-1.4 mg/dL; G3: 1.5-1.9 mg/dL; G4: ≥2 mg/dL. Baseline characteristics and  first-year rejection episodes were compared among these groups. Long-term graft survival was measured by deaths and death-censored graft loss (patients requiring hemodialysis, patients with 5-year e-GFR <30, and patients with 5-year e-GFR between 30 and 45). Outcomes were compared to determine the correlation between first-year serum creatinine and long-term graft outcomes.

Results:

The study involved 176 patients (72.16% males). Deceased donor transplants accounted for 57.96% (n=102). Mean recipient age was 31.3 years. Patients were divided into four cohorts, with the majority in G2 (68.18%, n=120), followed by G3 (19.88%, n=35), G1 (9.09%, n=16), and G4 (2.84%, n=5). The mean donor age was 37.7 years, with significant differences across groups (p=0.028). Donor sex and recipient age differences were not significant (p=0.268, p=0.721). Out of 176 patients, 40 had delayed graft function, predominantly from cadaveric donors. Delayed graft function significantly affected one-year graft survival (p=0.021). There were 23 first-year rejection episodes, predominantly acute cellular-mediated rejection (n=17). Rejections were significantly lower in G1 (6.25%) and G2 (7.5%) compared to G3 (28.57%) and G4(60%) (p<0.05). Long-term follow-up showed 17 deaths, with more deaths in G3 (n=10) than in G1 (n=2) and G2 (n=5) (p=0.01). Nine patients are currently on hemodialysis, with significant differences among groups (p<0.05). Five-year e-GFR values varied significantly, with better preservation in G1 and G2 compared to G3 and G4. Mean and median graft survival at 5 years were highest in G1 (137 and 125 months) and lowest in G4 (80 and 68 months)

Conclusions:

The study reveals that donor age, delayed graft function, and first-year rejection episodes significantly influence both one-year and long-term graft survival. However, donor gender, donor relationship, infections within first year  and recipient age do not significantly affect these outcomes. Additionally, one-year serum creatinine levels are identified as an independent and cost-effective biomarker for predicting long-term renal allograft outcomes.

I have no potential conflict of interest to disclose.

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