Histological changes associated with early and late renal allograft dysfunction in a large three-center transplant program in Iraq

Introduction: Transplantation is the sole viable option for the long-term survival of patients with end-stage renal disease (ESRD) in low-resourced countries. Objectives: To report the histopathological characteristics of kidney graft dysfunction in a large transplant program of a developing country. Patients and Methods: Renal transplant biopsies were analyzed by the Banff 2017 classification and subdivided into early (≤1 year) or late (>1 year) post-engraftment periods during the 12 months of 2019. Results: Here, 290 satisfactory graft biopsies were obtained on 290 patients for graft failure and/ or proteinuria. The median age of the recipient was 39 years (interquartile range 28-47), where 77% were male and 5.5% had been previously transplanted and 84% of donors were unrelated. Histological diagnosis was as follow; acute T-cell mediated rejection (A-TCMR; 23.1%), acute tubular necrosis (ATN; 14.8%), interstitial fibrosis and tubular atrophy (IFTA; 11.4%), recurrent or de novo kidney disease (R/DKD; 8.6%), transplant glomerulopathy (TG; 7.6%), calcineurin inhibitor toxicity (CNI; 6.9%), and active antibody-mediated rejection (A-AMR; 8.6%). Early graft dysfunctions were A-TCMR (29%) and ATN (22.4%). Late graft dysfunction included IF/TA, (20.2%), TG (20.2%), R/DRD (17%), and A-TCMR (9.5%). C4d+AMR was equally represented in early (5.6%) and late (6.3%) biopsies. Conclusion: A-TCMR was the most common cause of early graft dysfunction and was replaced by chronic conditions as the cause of 57.8% of late graft biopsies. The causes of graft dysfunction are not remarkably different from the west and TG will be a major cause of late graft failure in Iraq.