Noninvasive evaluation of renal allograft fibrosis by transient elastography - a pilot study

Abstract

Summary Chronic allograft injury (CAI) is the most common cause of graft failure after the first year of transplantation. To date, only protocol biopsies can reveal subclinical disease. Transient elastography (TE) is a novel noninvasive technique that has demonstrated high reliability in the assessment of liver fibrosis. This study evaluates the feasibility of TE for the assessment of renal allograft fibrosis. Fifty‐seven patients underwent TE by the FibroScan® device. Biopsies were performed in 20 patients. Measurement of parenchymal stiffness by TE was successful in 55 of 57 patients (96.5%). Stiffness was significantly correlated to the extent of interstitial fibrosis (Pearson r: 0.67, P: 0.002, R2: 0.45) and inversely related to estimated glomerular filtration rate (eGFR) (Pearson r: −0.47, P: 0.0003, R2: 0.22). Stiffness values of patients with an eGFR >50 ml/min were significantly lower than in patients with an eGFR ≤50 ml/min (22.2 ± 11.0 vs. 37.1 ± 14.2 kPa, P: 0.0005). The stiffness values of CAI Banff grades 0–1 differed significantly from grade 2 (P: 0.008) and grade 3 (P: 0.046). Parenchymal stiffness measured by TE reflects interstitial fibrosis in kidney allografts. A longitudinal assessment of parenchymal stiffness might be a powerful tool to identify patients with CAI who benefit from biopsy and consequent adaptation of the immunosuppressive regime.

Kidney Ultrasound Elastography: Review

“…Anyway, there is no adequate and reliable data about differentiating the grades of fibrosis [4][5][6][7][8][9][10][11][12][13][14] . Perhaps in near future these results should assist the clinicians to use elastography instead of biopsy.…”

“…We excluded these articles. The rest amount of related articles were 13 4,5,[8][9][10][11]13,14,25,[71][72][73][74] . But, pubmed search missed some articles 6,7,12,35,75 , that was mentioned in this paper (Table 1).…”

“…Some of them are functional, systemic and diffuse, while some are local and massy, and also vascular, congenital, hereditary and acquired 2,3 . Among all the disorders, chronic kidney disease (CKD) and transplanted kidneys are the subject of elastography in a majority of studies [4][5][6][7][8][9][10][11][12][13][14] . CKD is an important and costly health problem because of not only the increasing incidence and prevalence but also resulting in endstage renal failure.…”

Higher infiltration by Th17 cells compared with regulatory T cells is associated with severe acute T-cell-mediated graft rejection

“…Chronic injury is the most common cause of allograft failure after one-year from transplantation and is a significant determinant of long-term allograft outcome (Arndt et al, 2010;Nankivell et al, 2001). Accumulating evidence shows the role of Th17 cells in the progression of chronic injury in various disorders (Decraene et al, 2010;Syrjälä et al, 2010;Hammerich et al, 2011).…”

HMGB1, TGF‑β and NF‑κB are associated with chronic allograft nephropathy

“…The pathogenesis of CAN remains intricate and poorly understood, as the condition is caused by various immune and non-immune factors (5). For example, the immune factors include acute clinical rejection, human leukocyte antigen match, whereas non-immune factors consist of hypertension, glomerular hypertension, delayed graft function and acute calcineurin-inhibitor toxicity (6)(7)(8). These factors lead to cumulative damage to the kidney, which results in progressive allograft injury and consequently, dysfunction (9,10).…”