Clinical and Histopathological Characteristics of Biopsy-Proven Kidney Graft Rejection in Latvia

Kidney transplantation has become a preferred treatment for many patients with end-stage renal disease, leading to increased quality of life. In recent decades, results in kidney transplantation have been improving, but allograft rejection remains an important clinical problem. This retrospective study reviewed all kidney allograft biopsies performed at Pauls Stradiņš Clinical University Hospital from January 2014 to December 2022, with the aim to determine clinical and histopathological characteristics, treatment, and short-term outcomes of biopsy-proven kidney graft rejection in Latvia. Rejection was diagnosed according to clinical, laboratory, and biopsy-proven acute rejection histological criteria; classified and subdivided using Banff criteria (a total five groups). Treatment strategies, laboratory data at the time of biopsy and after one-year follow-up were analysed. A total of 153 allograft biopsies were included. The majority of the grafts were from deceased donors. Besides augmented maintenance immunosuppression for almost all patients, pulse steroids were the most administered treatment, followed by plasma exchange, rituximab, immunoglobulins, and anti-thymocyte globulin in different, mainly non-homogenous combinations. Acute antibody-mediated rejection was diagnosed most often. The most favourable outcomes considering allograft function were in the acute cellular rejection group after one-year treatment compared to the worst outcome chronic-active antibody mediated rejection (caAMR) group (p = 0.03). Furthermore, the caAMR group had the highest number of patients who returned to dialysis or died after one year.