Donor hepatitis C antibody positivity misclassifies kidney donor profile index in non-hepatitis C-infected donors: time to revise the kidney donor profile index - a retrospective cohort study.

Abstract

The kidney donor profile index (KDPI) defines an hepatitis C (HCV) positive donor based on HCV antibody (Ab) and/or nucleic acid amplification test (NAT) positivity, with donors who are not actively infected (Ab+/NAT-) also classified as HCV positive. From Scientific Registry of Transplant Recipients dataset, we identified HCV-negative recipients, who received a kidney transplant from HCV Ab+/NAT- (n=116) and HCV Ab-/NAT- (n=25574) donor kidneys. We then compared recipients' estimated glomerular filtration rate (eGFR) at 6months in matched cohorts, using combined exact matching (based on KDPI) and propensity score matching. We created two separate matched cohorts: for the first cohort, we used the allocation KDPI, while for the second cohort we used an optimal KDPI, where the HCV component of KDPI was considered negative in Ab+/NAT- patients. The mean±SD age of the allocation KDPI-matched cohort at baseline was 59±10years, 69% were male, 61% were white. Recipients' eGFR at 6months after transplantation was significantly higher in the HCV Ab+/NAT- group compared to the HCV Ab-/NAT- group (61.1±17.9 vs. 55.6±18.8ml/min/1.73m2 , P=0.011) in the allocation KDPI-matched cohort, while it was similar (61.8±19.5 vs. 62.1±20.1ml/min/1.73m2 , P=0.9) in the optimal KDPI-matched cohort. Recipients who received HCV Ab positive, but NAT-negative donor kidneys did not experience worse 6-month eGFR than correctly matched HCV Ab-/NAT- recipients.