S.A White

Sub‐clinical acute rejection detected using protocol biopsies in patients with delayed graft function

Abstract Acute rejection in renal transplants is difficult to diagnose when patients have delayed graft function (DGF) in the early post‐transplant period. In this study protocol, renal transplant biopsies were performed in an attempt to detect sub‐clinical acute rejection episodes. Eighty‐three patients were eligible for the study, of whom 33 had DGF. All had protocol renal transplant biopsies performed under ultrasound control at 7 days post‐transplant, and those with DGF had further biopsies weekly until the graft functioned. All histologically confirmed acute rejection episodes were treated. Sub‐clinical acute rejection was detected in 6/33 (18%) patients with DGF compared to 2/50 (4 %) in the other patients (P < 0.05). Borderline rejection was present in 4/33 (12 %) and 4/50 (8 %) patients, respectively. Because of the high detection rate of sub‐clinical acute rejection and the low morbidity of renal transplant biopsies, their use is recommended in patients with DGF.

Primary endoluminal stenting of transplant renal artery stenosis from cadaver and non-heart-beating donor kidneys

Abstract:  This study evaluated the efficacy of primary endovascular stenting in cases of transplant renal artery stenosis (TRAS) from cadaver and non‐heart‐beating donor kidneys. Patients with TRAS (n = 13) from a single‐centre transplant population (n = 476) were treated by primary percutaneous angioplasty and endovascular stenting. The short‐term efficacy of this intervention is demonstrated in terms of serum creatinine, glomerular filtration rate (GFR) biochemical, anti‐hypertensive medications and mean arterial blood pressure control. Stenting for TRAS was performed in male (n = 10) and female (n = 3) recipients. The median age at transplantation was 55 yr (range 10–67 yr). Stenting occurred at a median duration of 410 d post‐transplantation (range 84–5799 d). Mean serum creatinine (pre, 247 μmol/L; post, 214 μmol/L; p = 0.002), GFR (pre, 82.6 mL/min; post, 100.9 mL/min; p<0.001), arterial blood pressure (pre, 104 mmHg; post, 97 mmHg; p = 0.036) and the number of anti‐hypertensive medications required (pre, 3.4; post, 3.0; p = 0.002) showed significant improvement after post‐endovascular therapy. There were no serious complications encountered. Primary endovascular stenting of TRAS produces a significant improvement in biochemical parameters of renal graft function and in blood pressure stability, with the benefit of low patient morbidity and single arterial puncture. Primary endoluminal stenting of TRAS is a safe and effective procedure for the treatment of TRAS.

Fibrosis-associated gene expression in renal transplant glomeruli after acute renal allograft rejection.

Acute allograft rejection is thought to be a risk factor for chronic allograft nephropathy, the cardinal features of which are vasculopathy, interstitial fibrosis and glomerulosclerosis. Fibrosis‐associated genes might act as ad interim surrogate markers for chronic allograft nephropathy. The aim of this study was to determine mRNA expression of fibrosis‐associated genes in glomeruli plucked from protocol renal transplant biopsies, in patients with or without a history of acute rejection.

Pancreatic islet cell transplantation: Progress in the clinical setting

Pancreatic islet cell transplantation as a treatment for diabetes has hitherto been confined to small patient cohorts with limited success. This article summarizes the results of islet cell transplantation before and after the advent of the new ‘Edmonton protocol’ of immunosuppression and management of the donor pancreas. Adopting this regimen has achieved unprecedented success and renewed interest in this potential cure for diabetes. Central to recent improvements in the technique has been the transplantation of an adequate islet mass. Improved methods to procure, isolate, and purify islets for clinical use are now being adopted as a new ‘gold standard’. The use of new immunosuppressive drugs has further improved clinical results. Corticosteroid sparing-based regimens, and agents such as humanized monoclonal antibodies, are likely to form the mainstay of immunosuppressive protocols with the aim of achieving donor-specific tolerance. Alternative sources of islet cells are also required to expand the technique in an era of reduced numbers of donor pancreata. Manipulation of stem cells and xenotransplantation may yet yield sufficient islets to overcome the problem of donor shortage. Islet cell transplantation now forms the basis of a prospective multicenter trial under the aegis of the Immune Tolerance Network. The results of this are awaited, but it appears that islet cell transplantation may yet emerge as an effective treatment option for some members of the diabetic population.