Applications and new understandings of protocol biopsy during kidney transplantation / 中华器官移植杂志

Protocol biopsy (PB) is a planned needle biopsy of transplanted kidney and pathological observation for timely diagnosing the potential complications in transplanted kidney and guiding clinical interventions and adjusting immunosuppression regimen before an onset of dysfunction of transplanted kidney.With accurate information, it may grasp the baseline data of transplanted kidney histopathology.If detected early, timely measures may avert the existence of subclinical rejection or viral infection, avoid inflammation or injury and prevent various complications to ensure a better prognosis of transplanted kidney.At the same time, it is imperative to recognize the disadvantages of procedural biopsy, such as invasiveness, time consuming, greater patient discomfort and medical expenditure.This review focused upon the advantages and disadvantages of PB and its clinical application value.In light of the latest advances of clinical researches, favorable factors of PB are optimized for better long-term functional survival of transplanted kidney.

Application progress in classification of puncture biopsy after kidney transplantation / 器官移植

Renal allograft biopsy (biopsy) remains the "gold standard" for the diagnosis of renal dysfunction after kidney transplantation. Puncture biopsy after kidney transplantation could be divided into indicative biopsy and protocol biopsy according to renal function of the patients. Indicative biopsy is mainly applied to diagnose postoperative complications of kidney transplantation, evaluate the severity of disease and guide subsequent treatment. Protocol biopsy is primarily employed to regular monitor renal allograft function of kidney transplant recipients and exclude subclinical rejection and other complications. Due to the willingness of patients and other reasons, protocol biopsy has not been widely applied in China. Currently, indicative biopsy is the main biopsy pattern. At present, the indications of puncture of indicative biopsy, the timing and necessity of puncture of protocol biopsy remain controversial. In this article, the classification of puncture biopsy after kidney transplantation and research progress on tissue biomarkers based on biopsy were reviewed, aiming to assist clinical diagnosis and targeted treatment of complications after kidney transplantation and provide reference for further improving the survival of renal allografts and recipients.

Clinical Significance of Protocol Biopsy Soon after Renal Transplantation / 대한이식학회지

BACKGROUND: Several studies reported that sub-clinical rejection (SCR) detected by a protocol biopsy soon after renal transplantation does permanent damage to a renal allograft, contributing to chronic allograft nephropathy (CAN). This article investigated the risk factors involved in SCR and the effects of treating SCR, and evaluated the clinical significance of a protocol biopsy soon after renal transplantation. METHODS: From January 2007 to June 2010, 253 patients received renal transplantation. Patients were divided into two groups according to whether or not they had undergone a protocol biopsy. To analyze the effect of SCR treatments, patients who were diagnosed with SCR were divided into two groups according to whether or not they had been treated with SCR. The patients who did not undertake a protocol biopsy were included in the untreated groups. RESULTS: Among 138 patients who undertook protocol biopsies, 65 patients (47.1%) showed SCR. In univariate analysis, both the number of HLA-DR mismatches (P=0.003) and not using Simulect (P=0.01) were identified as risk factors of SCR. In multivariate analysis, not using Simulect (P=0.006) was identified as an risk factor independent of SCR. deltaGFR, subtracting GFR at 1 week from GFR at that point, showed significant differences between SCR-treated patients and untreated patients at 1, 3, 6, 9, 12, 24, and 36 months with a P value of less than 0.05. CONCLUSIONS: A protocol biopsy can detect SCR, especially in patients with risk factors such as a high number of HLA mismatches or not using Simulect. Treatment of SCR detected by protocol biopsy will help to improve long-term renal function.

Clinical Significance of Protocol Biopsy Soon after Renal Transplantation / 대한이식학회지

BACKGROUND: Several studies reported that sub-clinical rejection (SCR) detected by a protocol biopsy soon after renal transplantation does permanent damage to a renal allograft, contributing to chronic allograft nephropathy (CAN). This article investigated the risk factors involved in SCR and the effects of treating SCR, and evaluated the clinical significance of a protocol biopsy soon after renal transplantation. METHODS: From January 2007 to June 2010, 253 patients received renal transplantation. Patients were divided into two groups according to whether or not they had undergone a protocol biopsy. To analyze the effect of SCR treatments, patients who were diagnosed with SCR were divided into two groups according to whether or not they had been treated with SCR. The patients who did not undertake a protocol biopsy were included in the untreated groups. RESULTS: Among 138 patients who undertook protocol biopsies, 65 patients (47.1%) showed SCR. In univariate analysis, both the number of HLA-DR mismatches (P=0.003) and not using Simulect (P=0.01) were identified as risk factors of SCR. In multivariate analysis, not using Simulect (P=0.006) was identified as an risk factor independent of SCR. deltaGFR, subtracting GFR at 1 week from GFR at that point, showed significant differences between SCR-treated patients and untreated patients at 1, 3, 6, 9, 12, 24, and 36 months with a P value of less than 0.05. CONCLUSIONS: A protocol biopsy can detect SCR, especially in patients with risk factors such as a high number of HLA mismatches or not using Simulect. Treatment of SCR detected by protocol biopsy will help to improve long-term renal function.

Calcineurin inhibitor toxicity in renal allografts: Morphologic clues from protocol biopsies.

Background: Calcineurin inhibitors (cyclosporine and tacrolimus) are important constituents of post renal transplant immunosuppression. However, renal toxicity limits their utility. Histological features of calcineurin inhibitor toxicity (CNIT) have been the subject of few studies using protocol biopsy samples, and consensus on diagnostic criteria is still evolving. Aims: To analyze the spectrum of histological changes in protocol renal allograft biopsies with evidence of CNIT and identify additional features that are likely to help the pathologist in arriving at a diagnosis. Materials and Methods: One hundred and forty protocol allograft biopsies performed at 1, 6 and 12 months post renal transplant were studied. The defining features of CNIT included: isometric vacuolization of proximal tubular cells, arteriolar hyalinosis with medial/peripheral nodules and striped pattern of tubular atrophy/interstitial fibrosis. Other features such as global glomerulosclerosis, vacuolization of smooth muscle cells of arterioles, tubular microcalcinosis, ischemic shrinkage of glomeruli and hyperplasia of juxtaglomerular apparatus (JGA) were also analyzed and graded semiquantitatively. Results: CNIT was seen in 17/140 protocol biopsies (12.1%). In addition to the diagnostic criteria, arteriolar hyalinosis, smooth muscle cell vacuolization of arterioles and hyperplasia of JGA were found to be useful indicators of CNIT. Conclusions: There is a relatively high incidence of CNIT in protocol allograft biopsies. A critical analysis of renal biopsy in adequate number of serial step sections to identify these features is mandatory, as many of these features are subtle and are likely to be missed if not specifically sought.