体重<15kg儿童DCD单侧供肾用于成人肾移植的临床观察

目的评估体重15kg的儿童DCD(公民逝世后器官捐献,包括脑死亡捐献和心脏死亡捐献)供者单侧供肾用于成人肾移植的早期安全性及临床效果。方法回顾分析本院2013年2月至2015年2月间行体重15kg的儿童供肾成人肾移植18例(儿童供肾组),与同期成人供肾成人肾移植62例(成人供肾组)的临床资料,分析两组患者术后并发症;1个月、3个月、6个月及1年移植肾eGFR;术后6个月及1年人、移植肾存活率;儿童供肾组术后移植肾长径、eGFR的变化情况,蛋白尿、血尿发生情况。结果儿童供肾组DGF、AR、血管及泌尿系并发症发生率分别为22.22%、5.56%、5.56%和5.56%,成人供肾组为20.03%、3.26%、0%和0%(P均0.05);所有受者观察期间均未死亡,术后1个月儿童供肾组eGFR明显低于成人供肾组(P0.05),术后3个月、6个月及1年,两组eGFR无差异(P0.05)。儿童供肾组术后6个月及1年移植物存活率分别为93.80%和93.80%,而成人供肾组为98.20%和98.20%(P0.05);儿童供肾组移植肾eGFR、长径与术后时间呈正相关增长,观察期内儿童供肾组蛋白尿发生率与成人组相当,血尿发生率高于成人组。结论本组体重15kg的儿童DCD单侧供肾成人肾移植术后并发症、功能(依据eGFR评价)与成人组相当,供肾长径及移植肾eGFR在术后3~6个月可增至成人水平,低体重儿童单侧供肾成人肾移植手术并发症率低,近期效果满意,远期效果有待进一步观察。     

Sirolimus Versus Cyclosporine in Kidney Recipients Receiving Thymoglobulin®, Mycophenolate Mofetil and a 6-Month Course of Steroids

To evaluate the efficacy and tolerance of a calcineurin inhibitor (CNI)-free regimen, 145 renal recipients were prospectively randomized to receive either sirolimus (n = 71) or cyclosporine (CsA; n = 74). All patients received polyclonal antilymphocyte antibodies, mycophenolate mofetil (MMF) and steroids (6 months). The primary endpoint, estimated glomerular filtration rate (eGFR) was not significantly different at 12 months comparing sirolimus- and CsA-treated patients (60 +/- 27 vs. 57 +/- 21 mL/min). At 12 months, patient and graft survival, incidence of biopsy-proven rejection and rates of steroid withdrawal were not statistically different (97% vs. 97%; 90% vs. 93%; 14.3% vs. 8.6% and 82.8% vs. 84.1%, respectively). Delayed and slow graft function (SGF) was not significantly different (18.6% vs. 12.3% and 11.4% vs. 13.7%, respectively). In patients who remained on treatment according to protocol at 12 months, eGFR was significantly higher with sirolimus (69 +/- 19 vs. 60 +/- 14 mL/min, p = 0.01). Overall study drug discontinuation rates were 28.2% with sirolimus and 14.9% with CsA. Adverse events (wound complications, mouth ulcers, diarrhea, hypokalemia, bronchopneumonia) and proteinuria >0.5 g/24h (38.8% vs. 5.6%, p < 0.001) were significantly more frequent in sirolimus-treated patients. Cytomegalovirus (CMV) infections were significantly less frequent with sirolimus (6% vs. 23%, p < 0.01). A CNI-free regimen using sirolimus-MMF can achieve excellent renal function, but patients on sirolimus experienced a high rate of adverse events and study drug discontinuation.     

Early Subclinical Coronary Artery Calcification in Young Adults Who Were Pediatric Kidney Transplant Recipients

Coronary artery disease (CAD) is the leading cause of death in adults after successful kidney transplantation. Children who have undergone successful kidney transplantation are entering young adulthood; however, the prevalence and extent of CAD in this population is unknown. We conducted a pilot study in young adults with stable allograft function, who received kidney transplants as children to measure coronary artery calcification (CAC), a marker of coronary artery atherosclerosis and CAD. We evaluated 19 young adults after successful pediatric kidney transplantation for known CAD risk factors; these patients underwent noninvasive imaging with electron-beam computed tomography (EBCT) for measurement of CAC. Prevalence and quantity of CAC were then compared to asymptomatic individuals from the community. All patients had multiple risk factors for CAD. Mean age at evaluation was 32 years (range: 21-48 years). CAC is uncommon in individuals in the community in this age range; however, nearly half of our patients had CAC detected with the quantity of CAC comparable to asymptomatic individuals from the community 10-40 years older. These data suggest young adults who received pediatric kidney transplants are at increased risk for developing early CAC and need close monitoring to detect early CAD so as to prevent premature cardiac morbidity and mortality.     

Prospective Monitoring of Polyomavirus BK Replication and Impact of Pre-Emptive Intervention in Pediatric Kidney Recipients

Polyoma BK virus (BKV)-associated nephropathy (PVAN) is a relevant cause of poor renal allograft survival. In a prospective analysis, we monitored BKV DNA in blood and urine samples from 62 consecutive pediatric kidney recipients. In patients with BKV replication, we analyzed the impact of reduction of maintenance immunosuppression on viral load kinetics and PVAN in patients with BKV replication. BKV-specific immunity was concomitantly evaluated on blood samples of viremic patients, by measuring the frequency of BKV-specific interferon-gamma-producing and cytotoxic T cells, and BKV IgG antibody levels. At a median follow-up of 24 months, BK viruria was observed in 39 of 62 patients, while BK viremia developed in 13 patients (21%). In all viremic patients, immunosuppression reduction resulted in the clearance of viremia, and prevented development of PVAN, without increasing the rate of acute rejection or causing graft dysfunction. As a consequence of immunosuppression adjustment, an expansion of BKV-specific cellular immunity was observed that coincided with viral clearance. We conclude that treating pediatric kidney transplant patients pre-emptively with immunosuppression reduction guided by BKV DNA in blood is safe and effective to prevent onset of PVAN. BKV-specific cellular immunity may be useful to guide this intervention.     

Survival Advantage of Pediatric Recipients of a First Kidney Transplant Among Children Awaiting Kidney Transplantation

The mortality rate in children with ESRD is substantially lower than the rate experienced by adults. However, the risk of death while awaiting kidney transplantation and the impact of transplantation on long‐term survival has not been well characterized in the pediatric population. We performed a longitudinal study of 5961 patients under age 19 who were placed on the kidney transplant waiting list in the United States. Of these, 5270 received their first kidney transplant between 1990 and 2003. Survival was assessed via a time‐varying nonproportional hazards model adjusted for potential confounders. Transplanted children had a lower mortality rate (13.1 deaths/1000 patient‐years) compared to patients on the waiting list (17.6 deaths/1000 patient‐years). Within the first 6 months of transplant, there was no significant excess in mortality compared to patients remaining on the waiting list (adjusted Relative Risk (aRR) = 1.01; p = 0.93). After 6 months, the risk of death was significantly lower: at 6–12 months (aRR = 0.37; p < 0.001) and at 30 months (aRR 0.26; p < 0.001). Compared to children who remain on the kidney transplant waiting list, those who receive a transplant have a long‐term survival advantage. With the potential for unmeasured bias in this observational data, the results of the analysis should be interpreted conservatively.     

Laparoscopic Live Donor Nephrectomy: A Risk Factor for Delayed Function and Rejection in Pediatric Kidney Recipients? A UNOS Analysis

The impact of laparoscopic (vs. open) donor nephrectomy on early graft function and survival in pediatric kidney recipients (< or =18 years) is unknown. We studied 995 pediatric live donor txs reported to UNOS from January 2000 to June 2002, in two recipient age groups: 0-5 years (n = 212, 44% laparoscopic donors [LapD]) and 6-18 years (n = 783, 50% LapD). Delayed graft function (DGF) rates were higher for LapD versus open donor (OpD) txs (0-5 years, 12.8% vs. 2.5% [p = 0.004]; 6-18 years, 5.9% vs. 2.8% [p = 0.03]). Acute rejection incidence for LapD versus OpD txs was higher at 6 months for recipients 0-5 years (18.6% vs. 5.9%, p = 0.01) and 6-18 years (22.5% vs. 15.6%, p = 0.03), and 1 year for recipients 0-5 years (24.3% vs. 7.9%, p = 0.004). In multivariate analyses, significant independent risk factors for rejection at 6 months and 1 year were recipient age 6-18 years, pretx dialysis, LapD nephrectomy and DGF. Graft survival was similar for LapD versus OpD txs. In this retrospective UNOS database analysis, LapD procurement was associated with increased DGF and an independent risk factor for rejection during the first year, particularly for recipients 0-5-years old. Future investigations must confirm these findings and identify strategies to optimize procurement and pediatric recipient outcome.     

Acute Tubular Injury in Protocol Biopsies of Renal Grafts: Prevalence, Associated Factors and Effect on Long-Term Function

Acute tubular injury (ATI) is commonly observed in renal allografts, especially early after transplantation. This study analyzes prevalence and associated clinical conditions of ATI in serial protocol biopsies (pBx) and indication biopsies (iBx), and its impact on long-term graft function.
612 pBx from 204 patients taken at 6 weeks, 3 and 6 months, and 151 iBx performed within the first year of transplantation were evaluated. Prevalence of ATI in pBx was 40% (6 weeks), 34% (3 months) and 37% (6 months), and 46% in iBx. ATI was associated with delayed graft function and prolonged cold ischemia time in pBx, and with acute rejections in iBx. The GFR at 1 and 2 years after transplantation correlated inversely with the frequency of ATI in both pBx and iBx (p < 0.001). Prevalence of chronic changes at 6 months was not significantly related to ATI (patients without ATI: 36%, patients with multiple ATI findings: 54%).
ATI is linked to inferior long-term graft function. While this suggests lack of recovery from ATI with permanent allograft damage, the underlying molecular mechanisms need yet to be uncovered. Prevention of the potential pathogenetic factors identified in this study might be the key point to attain good long-term graft function.     

Conversion of Twice‐Daily Tacrolimus to Once‐Daily Tacrolimus Formulation in Stable Pediatric Kidney Transplant Recipients: Pharmacokinetics and Efficacy

The pharmacokinetics, efficacy and safety of once‐daily tacrolimus formulation (Tac‐OD) were assessed in 34 stable pediatric kidney transplant recipients. Enrolled patients received their dose of twice‐daily tacrolimus formulation (Tac‐BID) on study Days 0 through 7. On the morning of study Day 8, the total daily doses for patients were converted to Tac‐OD on a 1:1 basis and maintained on a once‐daily morning dosing regimen. Tacrolimus pharmacokinetic profiles were obtained on study Days 7, 14 and 28 (after dose adjustment). Although the mean C₀ concentrations (4.10 ± 1.16–3.53 ± 1.10 ng/mL, p = 0.004), and AUC_0–24 (151.8 ± 41.6–129.8 ± 39.3 ng h/mL, p < 0.001) were decreased significantly after a 1:1 based conversion, there was high interindividual variability. The dose of Tac‐OD was decreased in 26.5% and increased in 44.1% of patients. The resultant tacrolimus dose and pharmacokinetic profiles on study Day 28 were comparable to those on Day 7. There were no serious adverse events. In conclusion, Tac‐BID can be safely converted to Tac‐OD in stable pediatric kidney transplant patients with the heightened therapeutic drug monitoring. Effects of drug conversion on the cardiovascular risk factors, neurological side effects and adherence should be further evaluated.

     

Impact of Subclinical Inflammation on the Development of Interstitial Fibrosis and Tubular Atrophy in Kidney Transplant Recipients

Our aim was to study the impact of subclinical inflammation on the development of interstitial fibrosis and tubular atrophy (IF/TA) on a 1‐year protocol biopsy in patients on rapid steroid withdrawal (RSW). A total of 256 patients were classified based on protocol biopsy findings at months 1 or 4. Group 1 is 172 patients with no inflammation, group 2 is 50 patients with subclinical inflammation (SCI), group 3 is 19 patients with subclinical acute rejection (SAR) and group 4 is 15 patients with clinical acute rejection (CAR). On the 1‐year biopsy, more patients in group 2 (SCI) (34%, p = 0.004) and group 3 (SAR) (53%, p = 0.0002), had an IF/TA score > 2 compared to group 1 (control) (15%). IF/TA was not increased in group 4 (CAR) (20%). The percent with IF/TA score > 2 and interstitial inflammation (Banff i score > 0) was higher in group 2 (16%, p = 0.004) and group 3 (37%, p < 0.0001) compared to group 1 (3%). In a multivariate analysis, patients in groups 2 or 3 had a higher risk of IF/TA score > 2 on the 1‐year biopsy (OR 6.62, 95% CI 2.68–16.3). We conclude that SCI and SAR increase the risk of developing IF/TA in patient on RSW.     

Acute Humoral Rejection in an ABO Compatible Combined Liver–Kidney Transplant—The Kidney Is Not Always Protected

Combined liver–kidney transplantation has become a common practice for the treatment of patients with concurrent end-stage renal disease and end-stage liver disease. Liver transplantation in the setting of multiorgan transplantation is thought to have a protective effect against humoral rejection even when a positive crossmatch is obtained prior to surgery. In most centers, a pre liver–kidney transplant crossmatch is rarely performed because of the known immunoprotective effect of the liver allograft. In this report, a case of acute humoral rejection in the kidney allograft after a combined liver–kidney transplant is described. Although humoral rejection was treated using plasmapheresis, intravenous immunoglobulin and rituximab, the kidney required 3 months to recover function and finally progressed to chronic allograft nephropathy. A heightened index of suspicion for acute humoral rejection of the renal allograft is necessary when performing combined liver–kidney transplants to highly sensitized patients due to previous organ transplants.     

The Influence of Rejection Episodes in Recipients of Bilateral Corneal Grafts

We investigated whether a rejection episode in one graft was associated with rejection in the other graft, in recipients with bilateral corneal transplants. In a prospectively maintained, national register of 14 865 followed corneal grafts, 1476 patients with bilateral penetrating corneal grafts were identified. Occurrence of rejection was a risk factor for graft failure (p < 0.0001). Logistic regression was used to calculate the adjusted odds ratio for rejection in one eye following rejection in the other eye. In the subset of 1118 patients with bilateral grafts but no history of previous grafts or rejections in either eye, the adjusted odds ratio for a rejection episode in the first eye following rejection in the second was 3.27 (95% confidence interval, CI 1.85, 5.79; p < 0.001). The adjusted odds ratio was 2.04 (95% CI 1.07, 3.91; p = 0.03) for rejection in the second eye following rejection in the first. The median time between the first rejection episode in one eye and the first rejection episode in the other eye was 15 months. Patients with bilateral corneal grafts who suffer a graft rejection episode in one eye are at significantly greater odds of suffering a rejection episode in the other corneal transplant.     

Outcomes of Steroid‐Avoidance Protocols in Pediatric Kidney Transplant Recipients

Advances in immunosuppression have facilitated increased use of steroid‐avoidance protocols in pediatric kidney transplantation. To evaluate such steroid avoidance, a retrospective cohort analysis of pediatric kidney transplant recipients between 2002 and 2009 in the United Network for Organ Sharing database was performed. Outcomes (acute rejection and graft loss) in steroid‐based and steroid‐avoidance protocols were assessed in 4627 children who received tacrolimus and mycophenolate immunosuppression and did not have multiorgan transplants. Compared to steroid‐based protocols, steroid avoidance was associated with decreased risk of acute rejection at 6 months posttransplant (8.3% vs. 10.9%, p = 0.02) and improved 5‐year graft survival (84% vs. 78%, p < 0.001). However, patients not receiving steroids experienced less delayed graft function (p = 0.01) and pretransplant dialysis, were less likely to be African‐American and more frequently received a first transplant from a living donor (all p < 0.001). In multivariate analysis, steroid avoidance trended toward decreased acute rejection at 6 months, but this no longer reached statistical significance, and there was no association of steroid avoidance with graft loss. We conclude that, in clinical practice, steroid avoidance appears safe with regard to graft rejection and loss in pediatric kidney transplant recipients at lower immunologic risk.     

Quality of Life after Pediatric Intestinal Transplantation: The Perception of Pediatric Recipients and Their Parents

The objective was to examine the perception of physical and psychosocial functioning of pediatric intestinal transplant recipients who are beyond the perioperative period and compare these with normal and chronically ill children. Child and parent forms of the Child Health Questionnaire were administered to all 29 pediatric intestinal transplant recipients between the ages of 5 and 18 years who had had a small bowel transplantation 1 year previous and had a functional allograft. Comparison was made with published norms and scores for pediatric patients on hemodialysis. Intestinal transplant recipients (on average 5 years after intestinal transplantation and at a mean age 11 years) reported similar scores in all domains compared with normal children. Parents of intestinal transplant recipients noted decreased function in several domains related to their child's general health, physical functioning, and the impact of the illness on parental time, emotions and family activities. Intestinal transplant recipients beyond the perioperative period perceive their physical and psychosocial functioning as similar to normal school children. Parental proxy assessments differ from the recipients, with the parent's perception of decreased general health and physical functioning for intestinal transplant recipients compared with norms.     

Combined Pancreas and En Bloc Kidney Transplantation Using a Bladder Patch Technique From Very Small Pediatric Donors

Very small pediatric donors are underutilized for pancreas and kidney transplantation for the fear of inadequate islet mass and higher incidence of technical complications, and the lower age limit for such donors is not well defined. We present here two cases of combined pancreas and en bloc kidney transplantation from very small pediatric donors (14 and 18 months old) to adult type 1 diabetic and uremic patients. The conventional surgical procedure for simultaneous pancreas and kidney transplantation with systemic venous and bladder exocrine drainage was successfully applied to very small organs. For both, we utilized the recently described bladder patch technique for ureteral reconstruction. One patient developed venous thrombosis (partial thrombosis of the splenic and mesenteric veins) and the other urine leak (from a midportion of the medial ureter without compromising the bladder patch) after the transplants; both were successfully managed and the patients demonstrated immediate and sustained pancreas and kidney graft functions for 12 and 2 months posttransplantation. These cases illustrate the feasibility of combined pancreas and en bloc kidney transplantation from very small pediatric donors using a bladder patch technique to avoid small ureteral anastomosis.     

Clinical Features and Course of Kaposi''s Sarcoma in Egyptian Kidney Transplant Recipients

The prevalence of Kaposi's sarcoma (KS) after renal transplantation varies greatly depending on geographic and ethnic backgrounds. Out of 1400 live-donor kidney transplantation, 50 patients developed malignancy in our center. Kaposi's sarcoma was diagnosed in 24 patients (48%). Twenty patients were males and the main age of the patients was 29.8 +/- 11.1 years. They developed KS at a mean interval of 33.9 +/- 27.2 months, and the main duration of follow up was 62.2 +/- 50.7 months. Nineteen patients were cyclosporinee treated while four patients were azathioprine-based. Cutaneous KS was diagnosed in 20 patients, visceral in one, and three patients had both lesions. We found that the frequency of HLA-A1, -A2 and -DR5 were significantly common in KS patients. Titrated reduction of immunosuppression was initially tried in all patients. Bleomycin injection and superficial irradiation was tried in some cases. Response to therapeutic modalities was good in cutaneous form of KS. Twelve patients died (50%), two of them with functioning graft. We conclude that KS is the most common malignancy after kidney transplantation in our locality. Patients on cyclosporine are more prone to develop KS, and certain HLA-antigens may predispose to this. Early diagnosis and interference carry a favorable outcome.