多瘤病毒BK的监测在肾移植中的应用

目的 探讨血浆中多瘤病毒BK(BKV)检测在肾移植后患者发生BKV感染以及多瘤病毒相关性肾病(PAN)中的诊断价值.方法 对80例行同种异体肾移植术的患者和20例健康对照血浆中BKV DNA进行聚合酶链反应检测和序列分析,对检测结果进行对比分析.结果 扩增出的目的DNA片段长度为181 bp,与预期的病毒基因片段大小一致,测序结果与该病毒大T抗原的保守区域完全同源.80例肾移植后患者BKV检测为阳性12例(15.0%),最终发展为PAN的患者2例(2.5%);20例健康人BKV检测结果全部为阴性.结论 血浆BKV DNA监测是反映肾移植后患者是否发生病毒复制感染,并评价其患肾病的高危性的一个良好指征.对肾移植后患者发生PAN的确诊,需要结合临床上各种因素来综合分析.     

肾移植后BK病毒感染者实时荧光定量PCR检测

背景：对于BK病毒感染、BK病毒相关性肾病的认识缺乏规范的实验室诊断程序和标准化的无创性检验方法。目的：建立肾移植后患者尿液和外周血BK病毒感染负荷实时荧光定量PCR检测方法。方法：针对BK病毒基因组,自主设计特异性引物BKV-F和BKV-R,Taqman荧光探针BKV-P,Taqman荧光探针BKV-P的5’端标记有荧光基团,在除5’端外的任意一个位置上标记有淬灭基团;然后处理待测样本,进行PCR反应。结果与结论：将检测阳性的扩增产物进行基因测序,测序结果经BLAST比对后证实为BK病毒基因序列;利用上述方法对56份样本进行检测,其中,20份BK病毒血清样本及20份BK病毒尿液样本检测均为阳性,有S型扩增曲线。动态范围测定显示在103～1010copies/mL之间标准曲线具有良好的相关性。5份健康人尿液样本,5份血液样本及6份临床常见的其他病原体血液样本检测均为阴性,无S型扩增曲线。结果表明该方法可进行定性、定量检测,特异性好,反应快速,一般30min即可得到反应结果,并且成本低、假阳性少。     

肾移植后BK病毒感染者实时荧光定量PCR检测

背景:对于BK病毒感染、BK病毒相关性肾病的认识缺乏规范的实验室诊断程序和标准化的无创性检验方法.目的:建立肾移植后患者尿液和外周血BK病毒感染负荷实时荧光定量PCR检测方法.方法:针对BK病毒基因组,自主设计特异性引物BKV-F和BKV-R,Taqman荧光探针BKV-P,Taqman荧光探针BKV-P的5'端标记有荧光基团,在除5'端外的任意一个位置上标记有淬灭基团;然后处理待测样本,进行PCR反应.结果与结论:将检测阳性的扩增产物进行基因测序,测序结果经BLAST比对后证实为BK病毒基因序列;利用上述方法对56份样本进行检测,其中,20份BK病毒血清样本及20份BK病毒尿液样本检测均为阳性,有S型扩增曲线.动态范围测定显示在103~1010 copies/mL之间标准曲线具有良好的相关性.5份健康人尿液样本,5份血液样本及6份临床常见的其他病原体血液样本检测均为阴性,无S型扩增曲线.结果表明该方法可进行定性、定量检测,特异性好,反应快速,一般30 min即可得到反应结果,并且成本低、假阳性少.     

Quantification and identification of polyomavirus DNA in blood and urine of renal transplant recipients

A cohort of 201 kidney transplant recipients (KTR) including 7 patients with evidence of renal function deterioration (as defined by creatinine levels >20% over baseline values) was analyzed for polyomavirus DNA in blood and urine samples by a new quantitative polymerase chain reaction method. Of 201 patients, 14 (6.9%) were positive for polyomavirus DNA in blood (median level, 500 copies per milliliter of blood) including all 7 patients with renal function deterioration. Polyomavirus DNA detection in blood for diagnosis of renal function deterioration in KTR showed a sensitivity of 100% and a specificity of 96%, whereas positive and negative predictive values were 50% and 100%, respectively. Diagnostic value of decoy cells detection and polyomavirus DNA quantification in urine samples was negligible.     

Gastrointestinal carcinomas in renal transplant recipients

The development of malignancies in renal transplant recipients is well documented. Typically, these are cutaneous tumors or lymphomas. During the past 5 years, we have encountered six patients with documented carcinomas of the gastrointestinal tract, which developed after these patients received renal transplants. These carcinomas developed at an average of 10 years (range 2–16 years) after renal transplantation. There were three carcinomas of the colon, and one each of the esophagus, stomach, and anal canal. In many instances, the patients had examinations prior to transplantation which were normal. Several surveys of transplant recipients indicate there is an increased incidence of gastrointestinal tract malignancies after transplantation. These studies also recommend that screening of the gastrointestinal tract in long-term transplant recipients be performed. Since these patients are often imaged in the radiology department, radiologists must be aware of this possible complication.     

荧光定量聚合酶链反应检测移植受者的巨细胞病毒DNA载量

目的评价实时荧光定量聚合酶链反应(PCR)检测移植后受者的巨细胞病毒感染情况。方法应用定性PCR检测59例骨髓移植受者和9例肝移植受者的150份外周血标本中的巨细胞病毒DNA,比较外周血白细胞和血浆的检出差异;应用实时荧光定量PCR检测上述150份血浆样本和54份对照血浆中巨细胞病毒DNA载量。结果以实时荧光定量PCR为参照,定性PCR检测白细胞的敏感度和特异度分别为62·5%和95·5%;检测血浆的敏感度和特异度分别为57·5%和99·1%。所检测的150份血浆样本中,定量PCR阳性率为26·7%,阳性者其病毒拷贝数介于5·065×102~3·570×105/ml之间;对照组仅1例阳性,且拷贝数小于103/ml。临床调查显示病毒拷贝数大于5×103的患者具有较高的机会发展为巨细胞病毒病。结论实时荧光定量PCR是一个快速、敏感、特异的,可用于监测移植后患者巨细胞病毒感染的方法,帮助临床及早治疗,缩短治疗时间。     

Considerations for monitoring cyclosporine in transplant recipients

Cyclosporine (CsA) monitoring has remained controversial since the advent of the use of CsA in organ transplantation in the early 1980s. This article attempts to clarify for the clinical laboratory worker many of the vagaries associated with CsA monitoring by considering choice of sample matrix, the nature of metabolites, the technical specifications of the assay techniques used for therapeutic monitoring of CsA, comparison of results assessed by the various assays, and the pharmacokinetic considerations associated with choice of sampling time. Expectations for the degree of clinical usefulness achievable for CsA levels through further improvement in assay methodologies are also discussed.     

造血干细胞移植后BK病毒监测的临床意义

本研究旨在建立造血干细胞移植后BK病毒(BKV)感染的快速检测方法,探讨该方法的可行性和应用价值。根据BKV基因序列设计引物,构建用于检测的定量标准品,建立实时荧光定量PCR检测BKV的方法,并对36例造血干细胞移植术后患者的尿液标本中BKV含量进行检测。结果表明:成功构建了BKV的定量标准品和荧光定量PCR检测BKV的方法,并经过特异性、敏感性、稳定性和重复性验证;在36例造血干细胞移植患者中有20例尿液定量检测出BKV,阳性率为55.56%,尿液负荷量BKV拷贝数为2.46×104-7.8×109/ml。结论:BKV实时荧光定量PCR检测方法的建立对造血干细胞移植后出血性膀胱炎的早期诊断、预防、治疗具有重要意义。     

Virus infections in renal transplant recipients.

534 serum samples from 73 renal transplant recipients, 41 haemodialysis patients, and 99 blood and organ donors were examined serologically for antibodies against Cytomegalo, H. simplex (types 1 and 2), Varicella-zoster, Epstein-Barr, Adeno, Influenza, Parainfluenza, Respiratory syncytial, Measles, Picorna- and human Polyoma- Viruses. Serum specimens were stored in the lyophilized state until examined thus enabling a simultaneous testing of all samples belonging to one patient. All antigens, complement, and control antisera were prepared, lyophilized, and standardized in this laboratory. This has enabled the use of single batches of any preparation throughout the study. Serologic results with antigens of the Herpesvirus group (CMV, HSV and VZV) compared favourably with previous results showing that infections with these agents, especially with CMV, can frequently be encountered among transplant recipients. Our results have indicated a moderately increased incidence of infections with some Herpesviruses in haemodialysis patients as well. Infections with VZV, for instance, were as frequently demonstrated in these patients, as in transplant patients although the former received no immunosuppressive therapy. Serologic results with non-Herpesvirus antigens indicated an increased incidence of infections with Polyomavirus, Myxoviruses (Influenza, Parainfluenza and RS) and Picornaviruses among transplant recipients. The incidence of acute infections with RS virus among adults was unusually high and there is no evidence so far to indicate such a high frequency of RS infections in any other group of adults. We were unable to demonstrate acute infections with non-Herpesviruses among haemodialysis patients, even though most of the patients were followed over a period of more than 2 years. Virus isolation attempts were performed with samples of urines and biopsy or autopsy samples. 23 out of 28 cytopathic agents recovered from urines, throat-swabs and/or from organs of transplant recipients were identified as CMV. Two HSV type 1, 1 HSV type 2, and 2 Coxsackie B type 3 viruses were also isolated. No viruses were isolated from a series of 31 kidneys randomly selected among autopsy cases.     

Telmisartan pharmacokinetics in Japanese renal transplant recipients

BACKGROUND: Telmisartan is taken up into human hepatocytes by organic anion-transporting polypeptide (OATP/gene SLCO) and is glucuronized by uridine diphosphate-glucuronosyltransferases (UGTs) into the acylglucuronide, and it is then excreted by transporters such as multidrug resistance 1 (MDR1/gene ABCB1), multidrug resistance protein 2 (MRP2/gene ABCC2), or breast cancer resistance protein (BCRP/gene ABCG2). We elucidated the association of UGTs (1A1, 1A6, 1A7, 1A9 and 2B7), SLCOs (1B1, 1B3 and 2B1), ABCB1, ABCC2 and ABCG2 polymorphisms with steady-state telmisartan pharmacokinetics in 12 Japanese renal transplant recipients. METHODS: Recipients were given 40 mg of telmisartan for at least 6 months. Blood was sampled 1 y after transplantation. Plasma concentrations of telmisartan were measured by HPLC. RESULTS: In subjects with the ABCC2 -24C/T genotype, the maximum plasma concentration of telmisartan was significantly greater than that in C/C genotype (96.8 vs. 57.4 ng/ml, respectively, P=0.0094). In ABCC2 -24C/C, the second peak plasma concentration of telmisartan was observed 13 h after oral administration, but not ABCC2 -24C/T genotype group. There was no significant difference in the telmisartan pharmacokinetics between genotype groups of other transporters such as SLCO1B3, ABCB1 and ABCG2 or UGTs. CONCLUSIONS: ABCC2 genetic polymorphisms appear to strongly influence inter-individual variation of telmisartan pharmacokinetics. MRP2 may be predominantly involved in the telmisartan pharmacokinetics in humans.     

Urinary tract infection in renal transplant recipients

Urinary tract infection (UTI) is common in renal transplant recipients. Frequency of UTIs depend on many factors such as age, female gender, kidney function, co-morbidity, type and amount of immunosuppression, urological instrumentation and/or the follow-up period (short term or long term) after kidney transplantation. UTI may worsen graft and patient survival. A significant proportion of renal transplant recipients with UTIs may develop acute pyelonephritis (APN), which is an independent risk factor for deterioration of graft function. Renal transplant recipients with UTIs are often clinically asymptomatic as a consequence of immunosuppression. UTI, however, may progress to APN (particularly in the early post-transplant period), bacteraemia and the full blown picture of urosepsis. Strategies for long term prophylaxis and antimicrobial treatment of UTI in renal transplant recipients are discussed.     

Diltiazem use in tacrolimus-treated renal transplant recipients

BACKGROUND: Calcium channel blockers are widely used in the treatment of post-transplant hypertension but have the potential for drug interaction with calcineurin inhibitors. Renal allograft outcomes when diltiazem is used with cyclosporine have been reported, but similar data with tacrolimus are not available. METHODS: We performed a retrospective analysis of all our renal transplant recipients from March 1997 to March 2002 who were given tacrolimus, mycophenolate mofetil and prednisone. Patients were divided into two groups based on whether diltiazem was started in the first postoperative week. Outcome measures included renal function up to 2 years post-transplant, blood pressure (BP) control, tacrolimus exposure, and costs related to tacrolimus monitoring. RESULTS: Sixty-four patients constituted the diltiazem group and 32 the control group. Their baseline characteristics were similar. The mean average daily dose of diltiazem used was 213.95 mg/day. There was no difference in renal function, graft survival, or patient survival over 2 years. BP control was similar although the diltiazem group required more medication. Diltiazem was discontinued in four patients due to side-effects. There was no difference in tacrolimus-related side-effects between the two groups. There was also no difference in tacrolimus exposure, cost related to tacrolimus monitoring, or combined costs when the expense of diltiazem was added. CONCLUSION: Diltiazem use is acceptably safe and efficacious in renal transplant recipients treated with tacrolimus-based immunosuppressive therapy. It can be considered as a first-line antihypertensive in these patients and is cost neutral for tacrolimus use.     

Stressors in renal transplant recipients at six weeks after transplant

The purpose of this study is to identify stressors that renal transplant recipients report experiencing 6 weeks posttransplantation and compare them with stressors reported by Hayward et al. (1989). The sample consists of 48 adult renal transplant recipients. Stressors are measured by the Kidney Transplant Recipient Stress Scale. The most stressful item identified is the possibility of repeated hospitalizations, different from the Hayward Study in which possibility of rejection was the most frequently reported stressor. Nurses can use this information to better understand the stressors related to the renal transplant experience and to then develop appropriate interventions that can enhance clients' self-care actions.     

Detection of cytomegalovirus-specific IGM in renal transplant recipients

We have compared two IgM-specific cytomegalovirus (CMV) antibody assays, an immunofluorescence assay (IFA-M) and an enzyme-linked antigen immunoassay (ELA-M), with an assay for CMV total antibody (ELISA) and viral culture for the detection of active CMV infection in renal transplant recipients. Of 75 patients (49 ELISA negative pretransplant, 26 ELISA positive), CMV-specific IgM was detected in 35 (27 ELISA negative pretransplant, 8 ELISA positive) using the IFA-M assay and in 25 (16 ELISA negative pretransplant, 9 ELISA positive) using the ELA-M test. Of the 25 patients identified as positive by ELA-M, 21 had positive viral cultures post-transplant, two seronegative patients had evidence of infection indicated by post-transplant seroconversion, and two patients were seropositive pretransplant but remained viral culture negative throughout the follow-up period. ELA-M and CMV total antibody ELISA detected primary infection in renal transplant recipients equally well, but ELA-M was found to be superior to ELISA and IFA-M for detecting reinfection and reactivation infections.     

Emerging trends in infections among renal transplant recipients

Outcomes following renal and simultaneous kidney-pancreas transplants have improved significantly due to better surgical techniques and improved modalities of antirejection therapy. However, infection remains a significant cause of morbidity and mortality. The use of new modalities of immunosuppression and routine use of antimicrobial prophylaxis has changed the pattern of infections post-transplantation. Cytomegalovirus remains a significant problem and BK virus has emerged as an important pathogen. New antimicrobial agents are now available to treat infection, however, antimicrobial resistance remains a concern.     

西罗莫司对肾移植受者的转换治疗

背景:新一代的强效免疫抑制剂西罗莫司具有肾毒性少、抗增殖、抗肿瘤等作用,能够减少肾移植受者的肝肾毒性和严重感染等不良反应.目的:验证以神经钙蛋白抑制剂为主要免疫抑制方案出现一种或多种危险因素时,应用西罗莫司转换治疗方案的有效性及其安全性.设计、时间和地点:回顾性病例分析,于2003～06/2006-12在解放军南京军区南京总医院解放军肾脏病研究所完成.对象:肾移植后转换以两罗莫司为主的免疫抑制剂治疗的患者93例,男59例,女34例,年龄(38±11)岁.神经钙蛋白抑制剂肾中毒者13例、神经钙蛋白抑制剂肝毒性者26例、移植后糖尿病11例、慢性移植肾肾病33例、移植后并发肿瘤10例.方法:所有患者治疗方案都采用快速转换法,即2周内撤除神经钙蛋白抑制剂,口服环孢素A或他克莫司后4 h,口服西罗莫司,单次首剂负荷剂量6mg,之后维持剂量1.0～2.0mg/d.在服用第1剂西罗莫司后的5～7d检测第1次西罗莫司浓度,目标质量浓度6～10 μg/L.主要观察指标:动态观察西罗莫司转换后的血肌酐水平、急性排斥反应发生率、移植肾的丢失率、肺部感染和死亡率等.结果:西罗莫司转换治疗后,神经钙蛋白抑制荆肾毒性和肝毒性患者症状明显好转,血浓度维持在(5.1±1.2)μg/L,血肌酐由(297.72+150.28)μmol/L.降至(123.76±44.2)μmol/L,转换后肝功能恢复(24例,92.3%).高糖血症患者9例恢复正常,2例改善;17例血肌酐下降大于原肌酐水平的25%,有效率为51.5%;10例肿瘤发生于肾移植后6～43个月,8例稳定无复发,2例死亡.西罗莫司转换治疗6个月内发生急性排斥反应3例.并发症主要包括高脂血症和蛋白尿.3例死亡,6例返回透析治疗,2例移植肾摘除.转换治疗3年人肾存活率分别为90.9%和75.8%.结论:使用神经钙蛋白抑制剂的肾移植受者时出现一种或多种危险因素时,切换成西罗莫司和霉酚酸酯免疫抑制方案后不良反应减少.     

Acute bone-marrow oedema in cyclosporin-treated renal transplant recipients

Transient musculoskeletal pain may occur in renal transplant patients on cyclosporin (CyA). Of 28 consecutive patients transplanted in this unit between 20 January 1995 and 2 May 1996, eight (two published elsewhere) developed this problem. Before transplantation, three of the patients had received prednisone intermittently or continuously for 15, 5 and 2 years, for asthma, crescentic GN and SLE, respectively. All patients had normal hand radiographs prior to transplantation. Five developed acute rejection following transplantation requiring treatment with methylprednisolone; one also required OKT3 (7 days). Weight- bearing joints of the lower limbs became affected at 3-40 weeks (mean 14) following transplantation. MRI changes (T1-, T2-weighted and STIR images) were consistent with acute bone-marrow oedema. Bone scintigrams showed enhanced tracer uptake in affected joints. A spontaneous complete remission occurred in five patients within 4-16 weeks, and this was supported by serial imaging. The other patient underwent core decompression of the femoral heads with relief of symptoms, but MRI showed bilateral avascular necrosis (AVN) of the femoral heads. MRI proved useful in detecting acute bone-marrow oedema and its possible progression to AVN. The former may be either a distinct entity or a forerunner of AVN.      

Emerging trends in infections among renal transplant recipients

Outcomes following renal and simultaneous kidney–pancreas transplants have improved significantly due to better surgical techniques and improved modalities of antirejection therapy. However, infection remains a significant cause of morbidity and mortality. The use of new modalities of immunosuppression and routine use of antimicrobial prophylaxis has changed the pattern of infections post-transplantation. Cytomegalovirus remains a significant problem and BK virus has emerged as an important pathogen. New antimicrobial agents are now available to treat infection, however, antimicrobial resistance remains a concern.