300 Pediatric Renal Transplantations: A Single-Center Experience

Our objective was to relate the results of 300 consecutive kidney transplants performed in children at a single center.

PATIENTS AND METHODS

An analysis of kidney transplants was performed on patients less than 18 years old engrafted from May 1977 to August 2005.

RESULTS

Among 300 kidney transplants, 48% of the patients were female, 87% were Caucasian, and 13% were African-Brazilian. The mean age at transplant was 11.5 +/- 4.5 years with 39 (13%) less than 6 years of age. The most frequent etiology of renal failure was vesicoureteral reflux/obstructive uropathy (36%) followed by glomerulopathy (27%). The donor was deceased in 32.3% and living related in 77.7% (parents 82%). The mean posttransplant follow-up was 4.8 +/- 4.3 years. The initial immunosuppression was CyA + AZA + PRED in 45%; CyA + MMF + PRED in 9.6%; TAC + AZA + PRED in 7.3%; TAC + MF + PRED in 9.7%; or TAC + MF without PRED in 10%. Sirolimus was employed initially in three cases. Induction with OKT3/ATG occurred in three patients and 112 received an anti-IL2 receptor antibody. The 103 graft losses during 28 years of follow-up were secondary to chronic allograft nephropathy in 51 (49.5%), vascular thrombosis in 5 (4.8%), acute rejection in 12 (11.6%), and recurrence of original disease in 13 (12.6%). Sixteen (15.5%) died with functioning grafts. Graft survival in the first, fifth, and tenth year were 90%, 72%, and 59%, respectively. Patient survival in the first, fifth, and tenth years were 95%, 93%, and 85%, respectively, with infection as the main cause of death.

Plasmapheresis for Recurrent Posttransplant Focal Segmental Glomerulosclerosis

The high recurrence rate of focal segmental glomerulosclerosis (FSGS) in kidney transplant recipients suggests that such patients have a circulating factor that alters glomerular capillary permeability. Serum from patients with FSGS increases glomerular permeability to albumin. This permeability factor has been partially identified as a protein. The removal of this protein by plasmapheresis (PP) decreases proteinuria. In this study we report data on the therapeutic effects of PP in FSGS children with recurrence in the transplanted kidney. Three hundred pediatric (age <19 years) renal transplants were performed, including 21 patients (24 transplants) with FSGS as a cause of renal failure. Fourteen (58.3%) subjects experienced disease recurrence (proteinuria >1 g/m(2) per day) within 1 month after transplantation. Mean age patient was 12 +/- 4.3 years, including 83.3% Caucasians and 70.2% recipients of living donor grafts. Nine were treated with 10 cycles of PP (3 cycles/weekly), initiated immediately after recurrence (<48 hours). Immunosuppression included high doses of cyclosporine (C(2) levels of 1700-1800 ng/mL), mycophenolate sodium or mofetil, and prednisone. Thirteen patients were induced with anti-IL2 receptor monoclonal antibody (daclizumab/basiliximab). Among the patients who underwent PP, five (55.5%) achieved a complete remission and one (12%), a partial remission (1 g/24 hours). There were no cases of remission among the five patients who were not treated with PP. Those who achieved remission after PP experienced no recurrences during the 2.6 +/- 1.4 years follow-up. PP appears to be effective to treat recurrent FSGS following kidney transplantation. It should be started as soon as possible.

Conversion to Sirolimus in Pediatric Renal Transplantation Recipients

We retrospectively evaluated the efficacy and safety of sirolimus (SRL) in 16 pediatric renal transplant recipients, who were 9.4 +/- 4.1 years of age when they first received SRL. The indications for SRL therapy were rescue from steroid-resistant acute rejection (31.3%), neoplasia (31.3%), diabetes (12.5%), polyomavirus-associated nephropathy (6.3%), chronic allograft dysfunction (6.3%), calcineurin inhibitor nephrotoxicity (6.3%), and hemolytic uremic syndrome (6.3%). Mean follow-up after the switch to SRL was 17.7 +/- 15 months. The final immunosuppression was CNI + SRL + prednisone (PRED) in five patients, SRL + PRED in six, SRL + mycophenolate mofetil (MMF) + PRED in four, and SRL + MMF in one. The use of SRL in these selected pediatric renal recipients was successful, except when creatinine was high at the moment of conversion. Further studies are necessary to assess the beneficial outcomes versus adverse events among the pediatric transplant population receiving SRL for immunosuppression.

Do we need living unrelated organ donation in Brazil?

The remarkable success achieved by organ transplantation has also engendered the major problem of organ shortage. As a consequence, the use of living unrelated donors (LURD) has been proposed as an ethically justifiable alternative for developed nations to minimize their waiting lists for organ transplantation (OTx). This change in attitude has caused an ethical dilemma for developing countries like Brazil, which is struggling to increase the cadaver donor pool. Due to a huge socioeconomic gap of values and needs among nations, the incentive to use LURD in developed countries may not only produce a disincentive to cadaver organ donation but also stimulate organ trade in developing countries. In this paper we aimed to show that in Brazil, we do not need to use LURD because we have not optimized our cadaver donor pool. The exploitation of LURD might be a good option for developed countries, but it is not useful for developing countries. The Transplantation Society urgently needs to solve and clarify this problem by establishing basic ethical and justice principles that can serve as a guide for every country, throughout the entire process required, to achieve an adequate pool of cadaver donors.

Expanding criteria for the use of living donors: what are the limits?

The cadaver organ shortage has pushed the transplant community to extend the boundaries beyond the traditional criteria used for living donor transplantation. This new liberal policy involves: (1) the type of donor, such as emotionally related individuals, the direct or indirect interchange of donors, anonymous as well as rewarded donation; (2) challenging immunological criteria, using incompatible ABO blood types and or transplantation across a positive cross-match; (3) relaxing clinical criteria related to elderly, hypertensive, or obese donors, or patients with nephrolithiasis, fibromuscular renal artery disease, hematuria, or renal cell carcinomas. However, these practices may be dangerous. They must be clearly validated to promote a liberal policy of donor acceptance since it may carry a risk for both the donor and the recipient as well as for society. It is crucial to ensure the physical integrity of the donor as well as to provide guarantees, for instance a 1-year policy of life insurance, an indefinite long-term medical follow-up and the assurance of going to the top of the waiting list if the donor becomes uremic in the future.

Immunosuppression in pancreas transplantation: mycophenolate mofetil versus sirolimus

The use of mycophenolate mofetil (MMF) in pancreas transplantation has increased graft survival and decreased the incidence of acute rejections episodes (ARE), regardless of the choice of calcineurin inhibitor. The combination of MMF with tacrolimus (TAC) is the most common protocol, it is considered the gold standard for new protocols. In the last few years, there have been reports of a small number of patients treated with sirolimus (RAPA), usually combined with TAC. Patient and pancreas survival rates as well as the incidence of ARE were similar to protocols with TAC and MMF. Twenty simultaneous pancreas and kidney (SPK) transplantations were performed using an immunosuppressive protocol of TAC, RAPA, and steroids (STE) after 2000. The incidence of ARE was 25%; all episodes responded to STE. Only 2 patients (10%) displayed hypercholesterolemia requiring treatment with statins. The use of RAPA as an alternative to MMF is promising, although presently one with limited experience. The combination of MMF and RAPA with or without a calcineurin inhibitor is an option to be evaluated in the future.

Pregnancy outcome after renal transplantation

AIMS

The aim of our study was to evaluate the frequency and the outcome of pregnancies in renal transplant recipients at our center.

METHODS

This study involved the retrospective analysis of 405 childbearing female renal recipients for presence of risk factors, the outcome of pregnancy, and maternal and fetal complications.

RESULTS

Fourty-four pregnancies occurred in 41 patients (10.8%). Mean age at transplantation was 23.6 +/- 6.3 years (range, 12-38 years). Only in 5 pregnancies were there no risk factors. In 13 (29.5%) pregnancies, the previous creatinine level was >1.5 mg/dL, in 16 (36.45%), proteinuria was >500 mg/24 hours; 29 (65.9%) were hypertensive; 14 (31.8%) had a time between transplantation and pregnancy less than 2 years (mean time, 35.5 +/- 30.9 months; range, 3-120 months). The outcomes were 27 (61.4%; 11 term and 16 premature delivery) successful pregnancies, 6 (13.6%) spontaneous abortions, 10 (22.7%) therapeutic abortions, and 1 (3.2%) fetal death. Pre-eclampsia occurred in 9 (20.4%) pregnancies and eclampsia in 1 (2.2%). The mean weight of the offspring was 2195 +/- 490 g (range, 1300- 2980 g). There were 2 cases of acute fetal distress and 1 oligodramnios. Median creatinine level was 1.0 (range, 0.4-3.0) mg/dL before conception and 1.2 (range, 0.7-9.0) mg/dL 6 month after pregnancy (P <.001). The long-term patient and graft survival rates were similar for pregnant versus nonpregnant recipients in the childbearing age.

CONCLUSION

Most pregnancies were successful, although the premature delivery rate was high (36.4%). Only 5 conceptions occurred in the absence of risk factors. Pregnancy did not impair the patient and graft survival during long-term follow-up.

Organ transplants in Latin America

Latin America has carried out kidney transplantation for 45 years. Twenty-four countries perform kidney transplantations, 14 perform heart transplantations, 12 perform liver transplantations, 9 perform pancreas transplantations, and, 2 perform small bowel transplantations. Seventeen countries have nephrology societies, 10 have transplantation societies, and 10 have national transplant organizations. The potential donor rate, 40 to 100 per million population per year (pmp/y), is similar to that observed in developed countries, but the rate of potential notified donors is 5 to 25 pmp/y, and the rate of effective donors is lower, 2 to 12 pmp/y. Approximately 77,000 transplantations were performed in the region until 2001, 70,000 kidney transplantations, 4000 liver transplantations, and 2500 heart transplantations. The annual number of kidney transplantations in Latin America increased from less than 3000 in 1991 to almost 7000 in 2001. Latin America, with only 8.5% of the world population, performed 12.7% of the kidney transplantations. Future strategies to improve the transplantation situation in Latin America include the following: obtain financial coverage for all the population, establish a National Transplant Organization and registries with transplantation results, and improve cadaveric and living donation to 10 pmp/y each.