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151.
Research suggests that end-stage renal disease patients with elevated body mass index (BMI) have superior outcomes on dialysis. In contrast, low and high BMI patients represent the highest risk cohorts for kidney transplant recipients. The important question remains concerning how to manage transplant candidates given the potentially incommensurate impact of BMI by treatment modality. We conducted a retrospective analysis of waitlisted and transplanted patients in the United States from 1990 to 2003. We constructed Cox models to evaluate the effect of BMI on mortality of waitlisted candidates and identified risk factors for rapid weight change. We then assessed the impact of weight change during waitlisting on transplant outcomes. Decline in BMI on the waiting list was not protective for posttransplant mortality or graft loss across BMI strata. Substantial weight loss pretransplantation was associated with rapid gain posttransplantation. The highest risk for death was among listed patients with low BMI (13-20 kg/m(2), adjusted hazard ratio = 1.47, p < 0.01). Approximately one-third of candidates had a change in BMI category prior to transplantation. While observed declines in BMI may be volitional or markers of disease processes, there is no evidence that candidates have improved transplant outcomes attributable to weight loss. Prospective trials are needed to evaluate the efficacy of weight loss protocols for candidates of kidney transplantation.  相似文献   
152.
Deceased donor factors associated with poor graft outcome are well known, but how often these factors lead to livers left untransplanted is poorly defined. A nested, case-control study was conducted using the United Network for Organ Sharing (UNOS) database from 1987 to 2005. Only those donating >/=1 solid organ were included. Primary outcome was livers not transplanted (LNT, cases) versus transplanted (LT, controls). Primary variables for multivariate analysis were donor age and obesity. Covariates included donation after cardiac death (DCD), cerebral vascular accident death, viral serologies, cancer, ALT and bilirubin. There were 23 373 (26%) LNT's from 91 362 donors who donated at least one organ. Percent LNT fell over time (1987-1990: 48%; 1991-1995: 29%; 1996-2000: 21%; 2000-2005: 16%; p < 0.01). Increased age (odds ratio: 4.2, 95% confidence interval 3.6-4.9, p < 0.01) and obesity (2.1, 1.9-2.3, p < 0.01) were significantly associated with LNT across all time periods. Other significant factors included DCD and elevated ALT. For 2001-2005, population attributable risk indicate that age >40, abnormal ALT and obesity account for 32.6%, 25.3% and 9.2% of untransplanted livers, respectively. Use of expanded criteria livers has pushed LNT lower in spite of an aging and heavier donor population. Nevertheless, age and obesity still account for a significant portion of untransplanted livers.  相似文献   
153.
Antibody-mediated rejection (AMR) frequently causes refractory graft dysfunction. This randomized controlled trial was designed to evaluate whether immunoadsorption (IA) is effective in the treatment of severe C4d-positive AMR. Ten out of 756 kidney allograft recipients were included. Patients were randomly assigned to IA with protein A (N = 5) or no such treatment (N = 5) with the option of IA rescue after 3 weeks. Enrolled recipients were subjected to tacrolimus conversion and, if indicated, 'anti-cellular' treatment. All IA-treated patients responded to treatment. One death unrelated to IA occurred after successful reversal of rejection. Four control subjects remained dialysis-dependent. With the exception of one patient who developed graft necrosis, non-responders were subjected to rescue IA, however, without success. Because of a high graft loss rate in the control group the study was terminated after a first interim analysis. Even though limited by small patient numbers, this trial suggests efficiency of IA in reversing severe AMR.  相似文献   
154.
目的探讨治疗儿童难治型系统性红斑狼疮(SLE)积极、有效的方法.方法对2例病程分别为5年和7年,狼疮肾Ⅲ级和Ⅳ级,主要表现为持续性血小板减少、蛋白尿和浆膜炎的患儿进行CD34+细胞分选的自身干细胞移植.首先经惠尔血动员、CS-3000血细胞分离机获取单个核细胞,通过CliniMACS CD34+细胞分选仪分别得到了1.7×106/kg及1.0×106/kg CD34+细胞,采集物中分别尚存2×105/kg和1×104/kg的CD3+细胞.用CTX 50 mg/kg·d×4 d+ATG(Fresennius S 5 mg/kg·d×3 d)预处理.结果两患者分别于+9 d和+7 d获粒细胞重建,自+15 d起血小板维持于正常水平.现已分别随访13月和6月,原发病症状完全消失,自身免疫相关抗体全部转阴,但细胞免疫功能仍未恢复,CD4细胞仍处于低水平.结论CD34+细胞分选的自身干细胞移植治疗儿童难治型红斑狼疮近期疗效满意.  相似文献   
155.
Thrombotic microangiopathy is a rare but important finding in the context of organ transplantation. Acute renal insufficiency in the setting of hemolysis and thrombocytopenia, a triad that constitutes 'hemolytic uremic syndrome', can be associated with, or triggered by, conditions such as verocytotoxin-producing Escherichia coli, viral infections, malignant hypertension, scleroderma, allograft rejection, lupus erythematosus, pregnancy, and medications including mitomycin C, calcineurin inhibitors, and oral contraceptives. After renal transplantation, it can occur, as either a de novo episode, or recurrent disease. Calcineurin inhibitors have long been associated with post-transplantation thrombotic microangiopathy. Sirolimus has been used as a primary immunosuppressant in patients transplanted with a history of earlier hemolytic-uremic syndrome, and also as rescue therapy in patients with calcineurin-inhibitor-associated thrombotic microangiopathy. We describe four cases where there was significant thrombotic microangiopathy in the context of contemporaneous or contiguous calcineurin inhibitor and sirolimus usage. As the intrarenal cyclosporin concentration is thought to be significantly elevated when cyclosporin and sirolimus are used together, this may explain these findings, and mandates caution in their co-administration.  相似文献   
156.
157.
Background Cold ischemia time and the presence of postoperative hepatic arterial thrombosis have been associated with biliary complications (BC) after liver transplantation. An ABO-incompatible blood group has also been suggested as a factor for predisposal towards BC. However, the influence of Rh nonidentity has not been studied previously. Materials Three hundred fifty six liver transplants were performed from 1995 to 2000 at our hospital. BC incidence and risk factors were studied in 345 patients. Results Seventy patients (20%) presented BC after liver transplantation. Bile leakage (24/45%) and stenotic anastomosis (21/30%) were the most frequent complications. Presence of BC in Rh-nonidentical graft–host cases (23/76, 30%) was higher than in Rh-identical grafts (47/269, 17%) (P = 0.01). BC was also more frequent in grafts with arterial thrombosis (9/25, 36% vs 60/319, 19%; P = 0.03) and grafts with cold ischemia time longer than 430 min (26/174, 15% vs 44/171, 26%; P = 0.01). Multivariate logistic regression confirmed that Rh graft–host nonidentical blood groups [RR = 2(1.1–3.6); P = 0.02], arterial thrombosis [RR = 2.6(1.1–6.4); P = 0.02] and cold ischemia time longer than 430 min [RR = 1.8(1–3.2); P = 0.02] were risk factors for presenting BC. Conclusion Liver transplantation using Rh graft–host nonidentical blood groups leads to a greater incidence of BC.  相似文献   
158.
肝移植术后并发胆道狭窄和胆泥淤积影像诊断及介入治疗   总被引:1,自引:0,他引:1  
目的:评价肝移植术后胆道狭窄和胆泥淤积影像诊断及介入治疗的价值。方法:对39例肝移植术后并发胆道狭窄和胆泥淤积的影像诊断及介入治疗进行回顾性分析。结果:超声、T型管胆道造影、CT和MRI检查诊断胆道狭窄伴胆泥形成39例,38例介入治疗后胆道梗阻症状明显缓解;1例介入治疗后胆道梗阻症状未明显改善,后行外科胆管修补术。结论:T型管胆道造影或直接经皮胆道造影对肝移植术后胆道狭窄和胆泥淤积诊断特异性及敏感性最高,放射介入和内镜介入技术对其均发挥重要的治疗作用。  相似文献   
159.
目的:本研究的目的是观察注射疗法及复合小针刀疗法治疗肌筋膜疼痛综合征对自主神经系统功能的影响。方法:选择40例诊断明确的肌筋膜疼痛病人,随机分为两组,每组20例。Ⅰ组:采用注射疗法治疗;IS组:采用注射疗法加小针刀治疗。观察两组病人治疗前后心率变异(HRV)的频域变化,低频LF、超低频LLF、高频HF、低高频比LF/HF及心率变异指数HR-Ⅵ;用视觉模拟评分法(VAS)评定治疗前后疗效并随访观察其远期疗效。结果:①HRV频域指标组内比较:LF、LLF、HF以及HRVI治疗前舆治疗后1min比较有显着性差异(P〈0.05),与5min、10min比较有非常显着性差异(P〈0.01)。LF/HF治疗前与治疗后5min、10min比较有显着性差异(P〈0.05)。组间治疗后1、5、10min,两两比较无显着性差异。②组间比较:病人治疗后临床症状、VAS评分均较治疗前降低.治疗前后IS组有非常显着性差异(P〈0.01)。两组VAS降低率有非常显着性差异(P〈0.01)。③回访病例中,两组治疗有效率比较有显着性差异(P〈0.05)。结论:注射疗法以及复合小针刀疗法均可有效改善肌筋膜疼痛病人的自主神经功能,其机制可能是通过调节、稳定自主神经系统功能达到缓解疼痛。注射疗法复合小针刀疗法的远期疗效优于单纯注射疗法。  相似文献   
160.
目的 探讨靶心图上心肌灌注缺损区定量分析方法的可靠性、重复性及应用价值。方法 16例急性心肌梗死(AMI)行自体骨髓单个核细胞移植治疗的住院患者,于治疗前、治疗后45和90d行^99Tc^m-MIBI静息心肌灌注显像。在靶心图上勾画缺损区(在左心室靶心图中放射性计数低于40%的区域),并进行定量分析。结果 (1)不同操作者所得ROI结果之间的差异无统计学意义(t=0.52,P〉0.05)。(2)治疗后45d心肌灌注缺损区面积较治疗前缩小34.32%,差异有统计学意义(t=2.83,P〈0.05);治疗后90d心肌灌注缺损区面积较治疗后45d缩小14.77%,差异有统计学意义(t=2.51,P〈0.05)。示自体骨髓单个核细胞移植对缺血心肌的恢复有一定疗效,能够缩小梗死面积,且自体骨髓单个核细胞冠状动脉内移植治疗AMI的疗效在移植后早期(45d内)即有体现。(3)面积百分比是观察心肌灌注变化的重要定量指标。结论 该方法对心肌病变范围及严重程度能准确定量;对评价AMI骨髓于细胞移植术疗效有一定的价值。  相似文献   
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