Increase in Serum Amylase and Resistive Index After Kidney Transplant Are Biomarkers of Delayed Graft Function

Background: Both amylase and resistive index (RI) are routinely measured after kidney transplant and proposed as markers of delayed graft function (DGF). Material and Methods: This retrospective cross-sectional study analyzed amylase and RI in 269 renal transplant recipients before and after transplantation, and at discharge. An increase above 20% of total amylase with/without RI>0.7 were evaluated as prognostic markers of DGF, hospitalization length and risk of rejection. Results: Serum amylase increase >20% was found in 103/269 (38.3%) patients who showed DGF (45.6% vs. 25.3%, p=0.001) and had lower estimated glomerular filtration rate compared to those with an amylase increase <20% (42.0 +/- 21.7 vs. 49.8 +/- 23.2 ml/min, p=0.007). The double condition consisting of concomitant amylase increase >20% and RI>0.7 was associated with higher DGF occurrence (65% vs. 24%, p<0.001), longer hospital stay, lower eGFR at discharge, and higher risk of rejection. Conclusion: Patients with concomitant amylase increase >20% and RI>0.7 might require closer monitoring to diagnose DGF early and modify the therapeutic approach accordingly.