群体反应性抗体在肾移植中的意义

目的 研究群体反应性抗体（ＰＲＡ０在肾移植中的意义。方法 对１７８例肾移植患者进行了术前、术后ＰＲＡ检测。结果 肾移植术前ＰＲＡ阳性患者有２３例,肾移植术后发生急性排斥反应的为２０例。术后ＰＲＡ阳性受者５８例,发生排斥反应的有３４例。移植前后ＰＲＡ阴性患者有１０８例,有８例发生排斥。在肾移植患者中所产生的抗ＨＬＡ抗体的频率和ＨＬＡ抗原的分布不同。结论 ＰＲＡ检测对预测移植肾排斥有重要意义。     

肾移植受者群体反应性抗体监测的临床意义

目的 分析群体反应性抗体（PRA）监测对预测肾移植受者排斥反应发生的意义及探讨对高水平PRA受者的临床处理.方法 应用酶联免疫吸附分析法（ELISA法）动态监测肾移植受者的PRA水平,以PRA≥10%为阳性,10%≤PRA＜50%为低致敏、PRA≥50%为高致敏,并对37例术前高致敏患者行血浆置换.结果 1527例肾移植受者中,PRA阳性350例（22.9% ）,其中高致敏 94例（26.8% ）;PRA阳性组排斥反应发生率（21.1% ）高于PRA阴性组（3.8% , P〈0.01）, 术后PRA转为阳性组排斥反应发生率高于PRA无变化组（P〈0.01）,行血浆置换受者与未行血浆置换受者排斥反应发生率无差异（P〉0.05）,接受过移植、多次妊娠、多次输血受者易致敏,HLA-A、B、DR配型错配抗原〉3个受者急性排斥的发生率（16.9% ）明显高于错配抗原≤3个受者（1.7% , P〈0.01）.结论 动态监测PRA水平有助于预测排斥反应的发生.     

Plasmapheresis with intravenous immunoglobulin G is effective in patients with elevated panel reactive antibody prior to cardiac transplantation.

BACKGROUND: Patients with a PRA >10% are considered to be at greater risk for the development of not only acute cellular and humoral rejection but also increased mortality when compared to nonsensitized patients following transplantation. All patients with a PRA >10% at our institution are treated with plasmapheresis and intravenous immunoglobulin G immediately prior to cardiac transplantation. METHODS: Sixteen (Group 1) of 118 patients awaiting cardiac transplantation were found to be sensitized. These patients underwent plasmapheresis followed by 20 gm of intravenous immunoglobulin G (IVIG) immediately prior to cardiac transplantation. Group 1 was compared to the remaining 102 patients with a PRA <10% (Group 2). RESULTS: Despite more patients in Group 1 having a positive crossmatch, pulmonary hypertension, and requiring mechanical circulatory support, there was no statistically significant difference in length of stay or mortality at a mean follow-up of 21.6+/-15.0 months. There was no difference in the occurrence of mild, moderate or severe cellular rejection or humoral rejection in these sensitized patients when compared to Group 2. CONCLUSIONS: Pretransplant plasmapheresis followed by intravenous immunoglobulin G may be an effective therapy that obviates the need for a prospective crossmatch and allows sensitized patients to undergo cardiac transplantation. There is no increase in the post transplant length of stay, occurrence of rejection or short term mortality. Long term follow up is necessary to evaluate whether there is a difference in the development of late rejection, transplant vasculopathy and survival.     

大剂量免疫球蛋白对群体反应性抗体水平的影响

目的 研究大剂量免疫球蛋白对群体反应性抗体（PRA）的作用。方法 取15例PRA值较高的等待肾移植的患者血清，加入大剂量免疫球蛋白，进行体外抑制实验；其中5例患者静脉注射大剂量免疫球蛋白，进行了体内抑制实验，4例患者用药1个疗程（每周0.5g/kg，共4周），另一例用药2个疗程，2例PRA降至10％左右的患者分别接受了肾移植和胰、肾联合移植。结果 体外实验显示，患者血清中加入大剂量免疫球蛋白的淋巴细胞死亡率和淋巴细胞毒实验的阳性率均较对照组低；接受静脉注射大剂量免疫球蛋白的患者，PRA下降2％－51％，平均降幅为23％；接受肾移植的患者，术后给予常规免疫抑制治疗方案，曾发生急性排斥反应，经冲击逆转，肾功能正常；接受胰、肾联合移植的患者，术后未发生排斥反应，移植胰、肾功能正常。结论 静脉注射大剂量免疫球蛋白可降低部分高敏患者的PRA值，其作用与用药量大小成正比。     

Late cardiac reoperation after cardiac transplantation

BACKGROUND: The intermediate and long-term results of cardiac transplantation continue to improve. Subsequent cardiac procedures may be required to extend patient survival and protect graft function. METHODS: The medical records of all adult and pediatric cardiac transplant recipients who underwent a subsequent cardiac procedure at our institution were reviewed. RESULTS: Three hundred sixty patients have undergone primary orthotopic transplantation in our institution. Seventeen patients (12 adults, 5 children) underwent a subsequent procedure requiring cardiopulmonary bypass including cardiac retransplantation (10), coronary artery bypass grafting (3), ascending aortic replacement (2), tricuspid valve repair (1), and myotomy and myomectomy (1 patient). Mean interval from time of transplantation to second procedure was 8.3 years. There was one perioperative death. Two patients, both retransplants, died late postoperatively at 22 and 84 months, respectively. Overall mean follow-up in the late survivors is 26.6 months. All survivors are currently asymptomatic and doing well. CONCLUSIONS: A variety of subsequent cardiac procedures, in addition to retransplantation, can be performed safely in carefully selected cardiac transplant recipients. The intermediate term results are gratifying in terms of survival and freedom from symptoms.     

Pediatric cardiac transplantation

Pediatric cardiac transplant patients present many challenges to the medical community. These include such things as complex evaluations, preoperative heart failure support, complex operative interventions, and postoperative challenges in management. In spite of these challenges, survival outcomes for children undergoing a heart transplant have improved dramatically over the last two decades.     

BVS5000 support after cardiac transplantation

OBJECTIVE: This study examines short-term mechanical assist device support for cardiac transplant patients and compares their outcomes with nontransplant patients requiring similar support. METHODS: Of 350 cardiac transplant patients at our institution, 7 patients required mechanical ventricular assistance with the Abiomed BVS5000 assist device (Abiomed, Inc, Danvers, Mass) after transplant secondary to severe acute rejection with cardiogenic shock (n = 4) or primary graft failure (n = 3). Recovery of ventricular function, survival to discharge, and complications were determined for the transplant group and compared with a second group comprising all other patients supported with the BVS5000 at our institution (n = 15). Additionally, the results of prior series reporting mechanical ventricular support of the failing transplant heart are reviewed. RESULTS: Demographics and duration of support were similar between the groups. The transplant group had a higher wean rate from device relative to the nontransplant group (100% versus 13%; P < 0.01). Five of 7 in the transplant group achieved survival to discharge (71%), relative to 5 of 15 in the nontransplant group (33%). Complications between the two groups were similar, although the transplant group experienced a higher rate of renal insufficiency (57% versus 13%, P = 0.05). CONCLUSION: Severe acute rejection with cardiogenic shock and primary graft failure are two conditions that may warrant mechanical ventricular support in the cardiac transplant patient. Transplant patients with these conditions have a high rate of ventricular functional recovery, greater than nontransplant patients supported with the same device and for a similar period of time. Although the incidence of renal insufficiency was higher, the majority of transplant patients who were supported with the BVS5000 achieved survival to discharge.     

Orthotopic cardiac transplantation 30 months after successful dynamic cardiomyoplasty

Reports of cardiac transplantation after successful cardiomyoplasty are rare. We report the case of a 63-year-old man with intractable heart failure who underwent successful orthotopic cardiac transplantation 30 months after dynamic cardiomyoplasty.     

Long-term survival after pediatric cardiac transplantation and postoperative ECMO support

BACKGROUND: Graft failure after cardiac transplantation in children can be managed acutely with mechanical support, most commonly extracorporeal membrane oxygenation (ECMO). The purpose of this study was to evaluation the long-term outcome of ECMO support early and late after pediatric cardiac transplantation. METHODS: From February 1982 through October 2002, 168 patients underwent isolated cardiac transplantation. Twenty patients (11.9%) required mechanical support early or late after transplantation. Inpatient and outpatient records of these were reviewed. RESULTS: Indication for transplantation was complex congenital heart disease in 12, cardiomyopathy in 7, and graft failure (retransplant) in 1. One patient was also on ECMO preoperatively. Fifteen patients required circulatory support immediately or shortly (less than 6 weeks) after transplantation. The remaining 5 patients were placed on ECMO for ventricular dysfunction late (3 months to 7 years) after transplantation. In the perioperative ECMO group, 8 (53%) were successfully decannulated and subsequently discharged. Three of 5 (60%) patients placed on ECMO late were successfully decannulated, 1 of whom died in hospital 10 days later and 2 of whom are still alive. CONCLUSIONS: Mechanical circulatory support using ECMO can be a useful strategy is the management of graft dysfunction after pediatric cardiac transplantation both early and late postoperatively. The mortality rate is acceptable in this very high risk group of patients and long-term outcome is good.     

脱敏预处理对高致敏活体肾移植受者PRA水平和疗效的影响

目的分析双重滤过血浆置换(double filtration plasmapheresis,DFPP)等脱敏处理对等待活体肾移植的高致敏患者的群体反应性抗体(panel reactive antibody,PRA)滴度以及对移植术后疗效的影响。方法 11例PRA强阳性(人类白细胞抗原Ⅱ类抗体80%)患者为研究对象,所有患者既往均有肾移植史。其中5例为实验组,于手术前隔日行DFPP(3～7次),加用免疫抑制剂。实验组患者每次DFPP前后抽取的血清及滤过弃物均采用流式细胞法测定PRA滴度变化。其余6例患者为对照组,移植前未作脱敏预处理。术后观察排斥反应发生情况及临床疗效。结果实验组早期第1例患者做了7次DFPP并加其它免疫处理,前5次抗体滴度明显下降,但后两次处理后抗体出现反弹。其余4例患者经3～5次DFPP处理后,抗体滴度不断下降。移植术后11例患者均未发生超急性排斥反应,实验组中有1例(1/5)发生细胞性排斥反应,而无体液性排斥反应,对照组中有4例(4/6)发生细胞性排斥反应,有3例(3/6)并发体液性排斥反应。结论 DFPP结合其它免疫处理方法进行脱敏预处理,能有效降低肾移植术前PRA滴度,降低移植术后体液性排斥和细胞性排斥的发生风险。