Clinical and Histopathologic Spectrum of Primary Nonfunction in Renal Allografts

Background: Primary non-function (PNF) is a serious complication of renal allografts, occurring in a subset of patients with delayed graft function (DGF), where patients never have freedom from dialysis and may develop sensitization. Prior studies have examined donor and recipient variables implicated in DGF and PNF, but data on the underlying pathology is largely lacking. Methods: Data from the Scientific Registry of Transplant Recipients (SRTR) was merged with our biopsy database at Arkana Laboratories. Biopsies in patients with a history of DGF or PNF were identified. We compared all patients with PNF (n=57) and 500 patients with DGF to identify factors associated with PNF. Donor and recipient variables from the SRTR and kidney biopsy data were used to identify factors associated with PNF compared to those with DGF with >1 year of allograft function. Unpaired t-tests and Chi-Square analysis were used to evaluate for changes among groups. Results: Primary non-function was significantly associated with deceased donors with an older age, history of hypertension, terminal creatinine > 1.5 mg/dL, and cardiac death. Recipients with a higher BMI and history of diabetes were more likely to develop PNF. There was no impact of age, sex, race, or cause of ESKD. Kidney pathology on allograft biopsies (n=813 DGF without PNF, n=101 PNF), showed an increase in acute tubular injury, cortical necrosis, thrombotic microangiopathy, arterionephrosclerosis, oxalate nephropathy, and recurrent IgA nephropathy compared to patients with DGF who did not progress to PNF, and more often were without allograft rejection (Table 1). Conclusion: In patients with DGF progressing to PNF compared to DGF with recovery, vascular insults, oxalate nephropathy, and recurrent IgA nephropathy were more common. Therefore, identification of these entities on biopsy may identify patients at highest risk of graft failure.Table 1. Factors associated with PNF in renal allografts