Delayed Graft Function Under the Microscope: Surveillance Biopsies in Kidney Transplantation

Abstract

Delayed graft function (DGF) is a common complication of kidney transplantation and frequently leads to the necessity of surveillance biopsies. The purpose of this study is to describe the histological findings in surveillance biopsies of deceased donor kidney transplant recipients and evaluate the risk factors for graft outcomes. This is a monocentric, retrospective study including kidney transplant recipients that underwent a graft biopsy during the DGF period between January 2006 and July 2019. 356 biopsies were performed in 335 deceased donor transplant recipients. Biopsies were analyzed according to the Banff classification. The main histological findings were: acute tubular necrosis in 150 biopsies (42.1%), acute rejection in 96 biopsies (26.9%), and borderline findings in 91 biopsies (25.5%). In the multivariate analysis, recipient age (p = 0.028) and DGF duration (p = 0.005) were associated with rejection, antibody-induction with anti-thymocyte globulin (ATG) was protective (p = 0.001). The occurrence of rejection was associated with lower death-censored graft survival (log-rank; p = 0.009). Surveillance biopsies of kidney grafts experiencing DGF remain an essential tool for the care of kidney transplant recipients. The recipient’s age and duration of DGF are independent risk factors for acute rejection, while antibody-induction therapy with ATG is associated with protection from its occurrence.

Prevalence of renal pathological disorders in kidney transplant recipients: an observational study in the north of Iran

“…In some other studies, the average age of transplant recipients was lower than the average age of our study (23,24). Moreover, Castro Filho et al study showed a significant relationship between recipient's age and acute transplant rejection, which was not consistent with our study (25). Whereas, Özkul et al did not find a significant relationship between age groups of older and younger than 65 years and the rate of graft survival.…”

“…The most common pathological disorder in patients studied by Castro Filho et al, was acute tubular necrosis, and most of the transplant rejections were of the acute cellular type. This study was close to our study in terms of acute cellular transplant rejection, with the difference that the population of this study were patients with delayed graft function (25). In general, the incidence of transplant glomerulopathy is increasing and occurs in approximately 20 cases up to 5 years after transplantation.…”

Lectin-mediated, time-efficient, and high-yield sorting of different morphologically intact nephron segments

“…This also applies when individual nephron segments are to be sorted into sub-segments (e.g., convoluted and straight PT segments) or for a clean separation of CNT and CD. In the clinic, the availability and molecular characterization of such individual nephron segments or subsegments could help to address unmet medical needs in delayed graft function [ 5 ] or toxic nephropathies [ 27 ], which could help to better guide clinical management and to define safe therapy endpoints with the aim to reduce the risk of organ rejection or loss of renal function, respectively. However, while highly desirable, a clinical application of our method using surveillance biopsies is at this stage very speculative.…”

Delayed Graft Function and the Renin-Angiotensin System

“…Castro Filho et al 104 utilized biopsies from 356 adult recipients of kidney transplants who were clinically suspected to have DGF and found that 42.1% of these cases exhibited indications aligning with AKI by ATN. Although the precise molecular mechanisms remain not fully elucidated, a growing body of evidence proposes an important role for an acute inflammatory response and activation of the RAS in the pathogenesis of ATN and AKI.…”