首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
The most effective strategy for the prevention of cytomegalovirus (CMV) disease in lung transplantation has not been conclusively established. The aim of this study was to determine the efficacy of preemptive ganciclovir therapy for this purpose. Twenty-five consecutive adult patients positive for CMV before transplantation and surviving more than 30 days after the procedure were studied. Mean follow-up was 732.2 days (range, 210-1125). All patients received intravenous (IV) ganciclovir prophylaxis for the first 21 days and subsequently underwent frequent CMV antigenemia monitoring: weekly for the first 3 months, every 15 days between 3 and 6 months, and monthly thereafter. IV ganciclovir was given when antigenemia results were greater than 10 infected cells per 100,000 polymorphonuclears. The study group was compared with a historical group of 30 consecutive patients who had received IV ganciclovir prophylaxis and continued on oral ganciclovir up to day 120 posttransplantation. Eighteen of the 25 patients (72.0%) presented episodes of CMV infection. Six of the 25 patients (24.0%) had CMV disease, including 3 viral syndromes and 3 cases of pneumonitis. Four patients debuted with CMV disease, 1 of them with pneumonitis. CMV resistance to ganciclovir was observed in 2 patients. The incidence of infection was higher than in the historical group (72.0% vs 46.7%; P < .05), but there were no significant differences in the incidence of CMV disease (24.0% vs 40.0%; P = not significant [NS]). Mean time before onset of the first episode of disease was lower in the preemptive therapy group than in the comparison patients (82.8 days; range, 42-240 vs 175 days; range, 90-243; P < .05). In conclusion, preemptive therapy for CMV disease is as effective a prevention strategy as oral ganciclovir prophylaxis. However, the early appearance of CMV disease with preemptive therapy can make this approach inadvisable.  相似文献   

2.
It is unclear whether antithymocyte globulin (ATG) induction therapy in hepatitis C-positive (HCVpositive) liver transplant recipients influences the risk of developing recurrent HCV disease. Multiple acute rejection episodes and high-dose steroids and/or OKT3 used to treat acute rejection increase the risk of graft loss from HCV. We studied the impact of ATG induction on graft and patient survival in HCVpositive liver transplants performed since 1990. Recipients who died or lost their grafts within 1 month of transplantation were excluded. Second, third, and fourth grafts were excluded, as were patients with stage III or IV hepatocellular carcinoma. There were 443 cadaveric liver transplants in adult recipients, of whom 142 (32%) were HCV positive. The incidence of biopsy-proven acute rejection was less in patients who received ATG induction, 34.2% (ATG induction) versus 66.6% (no ATG induction) (P = .01). ATG induction did not influence the risk of graft loss from HCV-related disease (P ≤ .75). When only HCV-related graft loss was considered, 10-year graft survival for HCV-positive recipients was 74% (ATG induction) versus 68.2% (no ATG induction). Whether ATG induction was given or not had no significant impact on either overall graft survival (P = .39) or patient survival (P = .11) in HCVpositive recipients. Presented at the Fifth Biennial Meeting of the American Hepato-Pancreato-Biliary Association, Fort Lauderdale, Florida, April 14–17, 2005  相似文献   

3.
The Toronto Lung Transplant Program has been using a peri-operative desensitization regimen of plasma exchange, intravenous immune globulin, and antithymocyte globulin in order to accept donor-specific antibody (DSA)-positive lung transplants safely since 2008. There are no long-term data on the impact of this practice on allograft survival or the development of chronic lung allograft dysfunction (CLAD). We extended our prior study to include long-term follow-up of 340 patients who received lung transplants between January 1, 2008 and December 31, 2011. We compared allograft survival and CLAD-free survival among patients in three cohorts: DSA-positive, panel reactive antibody (PRA)-positive/DSA-negative, and unsensitized at the time of transplant. The median follow-up time in this extension study was 6.7 years. Among DSA-positive, PRA-positive/DSA-negative, and unsensitized patients, the median allograft survival was 8.4, 7.9, and 5.8 years, respectively (p = .5908), and the median CLAD-free survival was 6.8, 7.3, and 5.7 years, respectively (p = .5448). This follow-up study confirms that long-term allograft survival and CLAD-free survival of patients who undergo DSA-positive lung transplants with the use of our protocol do not differ from other lung transplant recipients. Use of protocols such as ours, therefore, may improve access to transplant for sensitized candidates.  相似文献   

4.
Presence of preformed lymphocytotoxic antibodies may represent a barrier to isolated intestinal transplantation (IITx). We developed an intravenous immunoglobulins (IVIg) based desensitization protocol for candidates with high panel-reactive antibodies (PRA). Six patients with a mean PRA of 72+/-22% were included in a four-level (L) protocol with escalating doses of IVIg (L1, L2), addition of mycophenolate mofetil (MMF) or plasmapheresis (L3); and anti-CD20 (Rituximab) (L4). Four of six candidates improved their PRAs (from a mean of 66.2% to 25.5%; P=0.01) and were successfully transplanted. At a mean follow-up of 8 months, number and severity of rejection episodes of protocol patients did not differ from patients with low PRA transplanted during the same period. These data support the use of IVIg to desensitize patients waiting for IITx. It increases the applicability of IITx, and reduces the waiting time and mortality on the waiting list with outcomes comparable to nonsensitized recipients.  相似文献   

5.
6.
OBJECTIVES: Rituximab, an anti-CD20 monoclonal antibody therapy, depletes B cells and suppresses antibody production. This study sought to describe the efficacy and safety of rituximab among seven highly sensitized kidney transplant patients. METHODOLOGY: A highly sensitized patient was defined as panel-reactive antibody (PRA) >30%, more than three pregnancies, or history of positive tissue crossmatch. Demographics, immunological risk profile, and immunosuppression were collected on all highly sensitized patients transplanted from March to July 2007 and given rituximab. We noted graft function as well as clinical events posttransplantation. RESULTS: The seven patients included in the study showed a mean age of 39 years (range = 17-60) and a mean follow-up of 3 months (range = 1.5-5). Their average PRA was 62% with mean HLA mismatches of three. Five patients (71%) were retransplantations; one had a history of a positive crossmatch, and two had multiple pregnancies. Two had donor-specific antibody, but negative tissue crossmatches. All had living donors. Six patients received a single dose of rituximab (375 mg/m(2)) 1 day prior to transplantation and one received two doses after 19 sessions of plasmapheresis. All were given tacrolimus, mycophenolate, and steroids combined with induction therapy using 30 mg alemtuzumab in 33%; two doses of 20 mg basiliximab in 33%; and seven doses of 1 mg/kg/dose of daclizumab in 14%. Mean shown creatinine levels were 1.1 and 1.2 mg/dL at 1 and 6 months posttransplantation. Two recipients experienced acute humoral rejections within 1 month after transplantation. Both were given steroid pulsing, one of whom was steroid-resistant necessitating alemtuzumab therapy and plasmapheresis. Graft function of both improved with creatinine values of 1.3 mg/dL on discharge. No episodes of infection were noted. CONCLUSIONS: Rituximab can be safely administered and may be effective to improve outcomes among highly sensitized kidney transplant patients.  相似文献   

7.
徐岳  胡小鹏 《器官移植》2021,12(6):676-681
人类白细胞抗原(HLA)致敏在过去被认为是肾移植的禁忌证,在过去的30年中,随着脱敏治疗策略和免疫抑制剂的不断进步,越来越多的高致敏患者跨过了这一障碍。然而,高致敏患者肾移植术后仍面临着较高的超急性排斥反应以及抗体介导的排斥反应发生率,制约着高致敏患者肾移植手术的成功及移植物的长期存活。寻找切实有效的脱敏治疗方案是目前器官移植研究的热点问题,本文将从目前的脱敏治疗策略、用于脱敏治疗的新型制剂以及脱敏治疗的获益与风险进行综述,对目前脱敏治疗的方法以及脱敏治疗未来的方向进行讨论,旨在为跨越免疫屏障、提高高致敏患者肾移植手术的成功率及术后受者生活质量提供参考。  相似文献   

8.
The use of OKT3 therapy is a major risk factor for opportunistic infections in liver transplant recipients. In the last 2 years, we prospectively randomized 100 patients receiving OKT3 therapy into either a control group (n = 50) or a prophylaxis group (n = 50). Prophylaxis consisted of six doses of intravenous immune globulin over 4 weeks and oral acyclovir for 3 months after OKT3 therapy. The two groups were comparable with respect to demographic, immunologic, and clinical characteristics. The regimen of prophylaxis resulted in (1) a significant reduction in the incidence of herpetic and Epstein-Barr viral infections; (2) no change in the incidence of cytomegalovirus infections; (3) a significant decrease in the incidence of fungal infections; and (4) fewer deaths due to sepsis. The incidence of viral and fungal infections was higher after OKT3 induction than after rescue therapy. Our conclusion is that opportunistic infections are frequent after OKT3 therapy in hepatic allograft recipients. Treatment with intravenous immune globulin and oral acyclovir is safe and effective in preventing non-cytomegaloviral and fungal infections in this setting, thus conferring a survival advantage with fewer deaths due to sepsis.  相似文献   

9.
Peri-operative immunoadsorption in sensitized renal transplant recipients.   总被引:10,自引:0,他引:10  
BACKGROUND: Re-transplanted kidney allograft recipients with high levels of panel reactive antibodies (PRA) are at increased risk of early immunologic graft loss. In these patients, prophylactic peri-operative antibody depletion by immunoadsorption (IA) could prevent humoral graft injury and thus, in combination with anti-cellular rejection therapy, improve graft survival. METHODS: Twenty re-transplanted and broadly immunized cadaver kidney recipients (median PRA reactivity 87%, range 55-100%) were treated with IA (protein A) immediately before transplantation and during the early post-transplantation period (median number of IA sessions 11, range 1-24). Patients received additional prophylactic anti-lymphocyte antibody therapy. Nineteen patients had a negative pre-transplant cross-match. In one patient, a positive cross-match was rendered negative by the pre-transplant IA session. RESULTS: One-year graft survival was 80% and patient survival 95%. Median (range) serum creatinine in functioning grafts was 1.6 (0.8-2.7) mg/dl at discharge and 1.5 (1.0-5.8) mg/dl at 1 year. Two grafts were lost due to acute vascular rejection, whereby one rejection occurred after withdrawal of immunosuppression due to septicaemia. One patient had acute cellular rejection, which was reversed by a second course of anti-lymphocyte antibody therapy. Thrombotic microangiopathy and surgical complications were the causes for one graft loss each. Retrospective immunohistochemistry revealed peritubular C4d staining, a presumed marker for humoral alloreactivity, in 12 out of 15 biopsies. CONCLUSIONS: These results suggest that prophylactic peri-operative IA and anti-lymphocyte antibody therapy might be an effective therapeutic strategy for the prevention of early graft failure in sensitized re-transplant recipients.  相似文献   

10.
Cytomegalovirus (CMV) infection remains a major complication in recipients of solid organ transplantation. Based on available evidence, most centers are committed to an aggressive strategy, especially in high-risk patients, consisting of the use of universal prophylaxis in the posttransplantation period of maximum risk (3 months). In seropositive recipients there is no ideal model for prevention, although there is more acceptance in the international community for preemptive therapy. This paper shows the results obtained after analysis of a cohort of 86 patients undergoing heart transplantation in 2005-2011 at the Virgen del Rocío University Hospital, Seville. The 86 patients followed a strategy of preemptive therapy for both high- and low-risk recipients based on the use of antivirals for a variable period of ∼3 weeks when rising antigenemia was detected, determined by polymerase chain reaction above a set threshold. The incidence of CMV disease in our cohort was 4.6%. There are no data available from randomized clinical trials to establish which of the 2 strategies is more effective and safer in these patients, although there is a little experience with preemptive therapy in high-risk patients. Given our positive results and considering the adverse effects of antiviral prophylaxis derivatives, together with the development of resistance and the economic cost, we suggest an individualized prevention strategy at each center.  相似文献   

11.
BACKGROUND: Lung transplant recipients are susceptible to complications from influenza infection. Antibody responses to influenza vaccination have been shown to be decreased in lung transplant recipients. Cellular immune mechanisms serve an important role in influenza clearance. The cellular immune response to influenza vaccination has not been studied in transplant populations. METHODS: Interleukin-2, interleukin-10, interferon-gamma, and granzyme B levels to the three viral antigens included in the 1999 to 2000 influenza vaccine were measured before and 4 weeks post-vaccination in 43 lung transplant recipients and 21 healthy adult controls. RESULTS: Interleukin-2, interleukin-10, interferon-gamma, and granzyme B levels did not increase from pre- to post-vaccination in the lung transplant group. Both pre- and post-cytokine levels were lower in the transplant group compared to the control group. Pre- and post-granzyme B levels did not differ significantly between the groups. The T-helper response in the control group varied with the different viral strains. A correlation between acute rejection episodes and the absence of both azathioprine and mycophenolate was found. CONCLUSIONS: Influenza vaccination does not stimulate a cell-mediated immune response in lung transplant recipients as judged by interleukin-2, interleukin-10, interferon-gamma, and granzyme B levels. Alternative prevention strategies may be needed.  相似文献   

12.
《Transplant immunology》2011,24(4):166-169
BackgroundReal-time PCR has emerged as the preferred diagnostic assay for CMV. However, its utility as a preemptive therapy tool for CMV disease and related outcomes in liver transplant recipients has not been fully defined.MethodsPatients comprised 117 consecutive liver transplant recipients who underwent CMV surveillance monitoring using real-time PCR. Preemptive therapy with valganciclovir was employed upon detection of viremia. Baseline viral load was considered high based on log values (median).ResultsCMV viremia developed in 54% (63/117) of the patients, including 77% of R−/D+, 63% of R+/D+, 43% of R+/D−, and 10% of R−/D− patients. Overall, 23% (15/63) of the patients had recurrent viremia; R− serostatus (p = 0.065) but not initial viral load correlated with recurrent viremia (p = 0.80). At 12 months post-transplant, CMV disease occurred in 0.85% (1/117) of the patients (R+/D + recipient). None (0/30) of the R−/D + patients had CMV disease. Patients with CMV viremia treated preemptively did not differ significantly from those who never developed CMV viremia with regards to bacterial or fungal infections, rejection, graft loss, mortality rate, and probability of survival at 12 months (p > 0.05 for all variables). The above outcomes also did not differ for patients with high (> 1.9 logs) vs. low viral load (< 1.9 logs) (p > 0.05 for all outcomes).ConclusionsPreemptive therapy guided by real-time PCR based monitoring led to outcomes in all patients or in those with high viral loads that were comparable to outcomes in patients who never developed viremia or had low viral loads, respectively. Late-onset CMV disease at 12 months was observed in < 1% of all patients.  相似文献   

13.
A high level of panel-reactive antibodies (PRA) in potential renal transplant recipients is associated with a long waiting time until transplantation and correlates inversely with graft outcome. We report our experience with the employment of immunoadsorption (IA) using a column composed to sepharose-bound staphylococcal protein A (which has a relatively selective affinity for binding IgG compared with other immunoglobulins) to decrease the PRA levels and expedite transplantation in 6 highly sensitized potential renal transplant recipients (1 primary and 5 awaiting second transplants). All patients had PRA levels of greater than or equal to 70% for a duration of 1 year prior to IA. Only patients with antibody specificity localized to 1 or 2 HLA A or B antigens were accepted for the study. IA procedures were performed on alternate days until a twofold decrease in antibody titer had occurred (maximum: 6 procedures). Repeat procedures were initiated if the HLA antibody titer returned to its baseline value. Intravenous cyclophosphamide (CY) (10 mg/kg/day every 3 weeks) and methylprednisolone (MP) (0.5 mg/kg/day) were provided as adjunctive immunosuppression until transplantation. A total of 44 immunoadsorption procedures were performed (27 primary and 17 repeat) with treatment of 2.49 +/- 0.02 plasma volumes per session. Serum IgG concentration decreased 95 +/- 3% and PRA activity decreased 75 +/- 16% after the primary treatment course. Four patients received cadaveric grafts within 3.7 +/- 1.2 months following the last IA procedure. Three grafts are functioning at 1 year, 8 months, and 8 weeks posttransplant. The remaining graft demonstrated primary nonfunction. All four patients had a past positive crossmatch using pre-IA sera with their respective donors. Patients not transplanted exhibited rapid resynthesis of IgG and a return of the PRA towards baseline levels within a few weeks after IA. We conclude that IA can effectively remove HLA antibodies and expedite graft availability in highly sensitized patients.  相似文献   

14.
Eight female lung transplant recipients, all of whom became pregnant after transplant, were reported to the National Transplantation Pregnancy Registry from US transplant centers. Outcomes of the 8 pregnancies were 4 live births, 3 therapeutic abortions, and 1 spontaneous abortion. Three of the 4 newborns were premature, with low birth weight (< 2500 grams). Rejection during pregnancy occurred in 3 pregnancies (38%). All 8 transplant recipients reported at least 1 complication during pregnancy, including shortness of breath, rejection, and infection. Two of the 4 deliveries were by cesarean section. At follow-up, all children were developing well with no residual problems. Female lung transplant recipients may face higher risks during pregnancy than other solid organ transplant recipients.  相似文献   

15.
16.
Steroid resistant rejection, confirmed histologically, occurred in 35 of 187 consecutive cadaveric renal transplants treated with triple therapy (cyclosporin, azathioprine and prednisolone) in the Oxford Transplant Unit. Twenty-seven of these were treated with a rabbit antithymocyte globulin (ATG) and 19 showed recovery of function. The level of serum creatinine, the renal biopsy appearance and the requirement for dialysis at the start of ATG treatment did not predict which patients would respond to the therapy. One year after transplantation there was no significant difference between the mean plasma creatinine levels of those patients with steroid resistant rejection who had been given ATG and responded (151.6 μmol/l) and those who had responded to steroids alone (165.0 μmol/l). Adverse effects of ATG treatment included a mean fall in white cell count of 62.2% and a mean fall in platelet count of 45.1%. Two of the 27 patients who received ATG died (7.4% mortality). ATG would appear to be an effective treatment of steroid resistant rejection in patients receiving triple therapy immunosuppression, and graft function may subsequently be excellent in those patients who respond to treatment.  相似文献   

17.
BACKGROUND: Post-lung transplant infection is one of the leading causes of morbidity and mortality. The cause and incidence are similar in many series; however, infections such as Mycobacterium tuberculosis are influenced by the epidemiologic situation. The authors present a prospective and observational study to define the incidence, clinical presentation, and course of tuberculosis in a cohort of lung transplant patients at a single center in Spain. METHODS: Between 1990 and 2002, cutaneous delayed-type hypersensitivity testing and pathologic and microbiologic study of explanted lungs were conducted in 187 lung transplant patients. Serial bronchoscopies with transbronchial biopsy and bronchioalveolar lavage were performed during follow-up. The diagnosis of tuberculosis was established only when M. tuberculosis was identified in any sample or when histopathologic study was conclusive. RESULTS: Forty-eight patients were classified as anergic (25.6%) and 61 (32.6%) were classified as having a positive tuberculin skin test. Of the 109 patients, 95 received latent tuberculosis infection prophylaxis. Tuberculosis was diagnosed in 12 patients (6.41%); in six of them, diagnosis was determined from the explanted lungs. The remainder were diagnosed during follow-up. Fever and dyspnea were the most common symptoms. Chest radiographic findings presented an alveolar pattern. All patients responded well to antituberculous therapy; no deaths were attributable to tuberculosis. CONCLUSIONS: In the authors' experience, tuberculosis is not rare in lung transplant patients and can be managed successfully with antituberculous therapy without rifampin. A systematic protocol for diagnosing tuberculosis of the explanted lung is useful for reducing tuberculous complications of the implanted lung.  相似文献   

18.
Hypogammaglobulinemia in lung transplant recipients   总被引:6,自引:0,他引:6  
BACKGROUND: Infectious complications continue to represent a significant source of morbidity and mortality in lung transplant recipients. Identifying specific, remediable immune defects is of potential value. After one lung transplant patient with recurrent infections was noted to be severely hypogammaglobulinemic, a screening program for humoral immune defects was instituted. The objectives were to define the prevalence of hypogammaglobulinemia in lung transplant recipients, assess levels of antibody to specific pathogens, and correlate infectious disease outcomes and survival with immunoglobulin levels. METHODS: All lung transplant recipients followed at a single center between October 1996 and June 1999 underwent a posttransplant humoral immune status survey as part of routine posttransplant follow-up. This survey consists of total immunoglobulin levels (IgG, IgM, IgA), IgG subclasses (IgG1-4), and antibody titers to Pneumococcus, diphtheria, and tetanus. Since February 1997, this survey has been incorporated into the pretransplant evaluation as well. Humoral survey results for October 1996 through July 1999 were recorded, and clinical information on major infectious disease outcomes was obtained from chart reviews, discharge summaries, the Cleveland Clinic Unified Transplant Database, and review of all microbiological studies and pathology results for each patient. RESULTS: Of 67 patients with humoral immune surveys drawn posttransplant, 47 (70%) had IgG levels less than 600 mg/dl (normal 717-1410 mg/dl), of which 25 (37%) had IgG levels less than 400 mg/dl ("lowest IgG group") and 22 (33%) had IgG levels between 400 and 600 mg/dl ("moderately low IgG group"). A total of 20 patients (30%) had IgG levels of more than 600 mg/dl ("normal IgG group"). Infections that were significantly more common in the lowest IgG group, and more common in the moderately low IgG group than the normal IgG group, included: number of pneumonias (P=0.0006), bacteremias (P=0.02), total bacterial infections (P=0.002), tissue-invasive cytomegalovirus (P=0.01), invasive aspergillosis (P=0.001), total fungal infections (P=0.001), and total infections (P=0.006). Median hospital days per posttransplant year was significantly different in the three groups (11.0 vs. 7.4 vs. 2.8 days, P=0.0003.) Invasive aspergillosis occurred in 44% of the lowest IgG group, 9% of the moderately low IgG group, and 0% of the normal IgG group (P<0.001). Survival was poorest in the lowest IgG group and intermediate in the moderately low IgG group. IgG subclass deficiencies occurred in a variety of patterns. Hypogammaglobulinemic patients lacked protective responses to Pneumococcus in 14/47 (30%), diphtheria in 15%, and tetanus in 19%. In a group of 48 patients screened pretransplant, 90% had normal immunoglobulin levels. CONCLUSIONS: Hypogammaglobulinemia in lung transplant recipients is more common than has been previously recognized. An IgG level of less than 400 mg/dl identifies a group at extremely high risk of bacterial and fungal infections, tissue-invasive cytomegalovirus, and poorer survival. Immunoglobulin monitoring may offer an opportunity for intensive surveillance, tapering of immunosuppression, and preemptive therapy for infection.  相似文献   

19.
20.
In lung transplant recipients, cytomegalovirus (CMV) has been associated with direct ie, organ and systemic infection/disease, and indirect effects, including predisposition to develop acute rejection episodes and chronic allograft dysfunction. Cellular immune responses have been demonstrated to play a role in the control of CMV replication. We evaluated CMV-specific cellular responses among lung transplant recipients associated with the onset of organ infection/disease. Cellular responses were evaluated by an Elispot assay of 48 specimens from 24 patients. All samples were evaluated beyond 1 year after transplantation; CMV DNA was concomitantly detected in bronchoalveolar lavage (BAL) and whole blood specimens. Each patient received a combined prolonged antiviral prophylaxis with CMV Ig for 12 months and gancyclovir or valgancyclovir for 3 weeks after postoperative day 21. Nine patients (37.5%) showed transient or persistent CMV nonresponses including donor-recipient negative serologic matching in 2 cases. Positive CMV DNA results were observed in 18/48 BAL specimens (37.5%) from 12 patients (50%). A viral load of >104 copies/mL was observed in only 3 cases, 2 of whom were positive also on whole blood. Among these 3 patients, 2 were responders and BAL (as well as whole blood) specimens collected subsequently were negative for CMV DNA; 1 nonresponder patient exhibited a viral load of 426,492 copies/mL BAL (DNAemia, <2,000 copies/mL), developed CMV pneumonia (confirmed by histopathology and immunohistochemistry) and died within 28 days. The prevalence of CMV DNA positivity on BAL did not differ in relation to the immune response; the mean viral load on BAL showed significantly higher results among nonresponders than responders, namely, 1.4 × 105 ± 2.4 × 105 copies/ml versus 7.9 × 103 ± 1.4 × 104 (P = .02). Evaluation of CMV-specific cellular immune responses by in vitro immunologic monitoring complements virologic monitoring, helping to identify lung transplant recipients at risk of developing organ infection/disease.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号