Conversion from Prograf to Advagraf in stable paediatric renal transplant patients and 1-year follow-up.

BACKGROUND: The conversion from Prograf to Advagraf on a 1:1 (mg:mg) basis has been questioned in light of the publication of studies showing a decrease in tacrolimus blood concentrations after the administration of Advagraf. METHODS: The bioavailability of Prograf and Advagraf was evaluated in an open-label conversion study in 21 stable renal transplant paediatric patients. Serial blood samples for determining tacrolimus levels were collected during a 24-h period before (on Prograf) and after (on Advagraf) conversion. Tacrolimus pharmacokinetic parameters were calculated using a non-compartmental approach and the relative bioavailability calculated. Clinical and analytical data were obtained at 30, 90, 180 and 360 days after study enrolment. RESULTS: The mean ratio and 90 % confidence interval (CI) for peak plasma drug concentration (C(max)) and the area under the time-concentration curve during the first 24 h (AUC(0-24)) were 81.54 (95 % CI 71.6-92.87) and 87.19 (95 % CI 79.91-95.13), respectively. Renal glomerular filtration rate remained stable over the course of the follow-up. Two patients presented clinical events unrelated to tacrolimus. Tacrolimus levels decreased in the first month, the dose/level ratio increased between months 1 and 6 and slight dose adjustments were required during the follow-up period. CONCLUSIONS: Our results show that Advagraf bioequivalence cannot be ensured in this population. Significant changes in tacrolimus levels and dose were observed on long-term follow-up.

Living-donor transplantation after excision of unrecognized renal cancer diagnosed after transplant.

BACKGROUND: Published data on kidneys transplanted after resecting small renal cancers during the transplantation surgery are very rare and, to the best of our knowledge, no pediatric cases have been reported in the literature. CASE-DIAGNOSIS/TREATMENT: Our patient was diagnosed with a bilateral Wilms tumor when he was 15 months old. A total bilateral nephrectomy was required to control the disease. Two years later, a human leukocyte antigen (HLA)-identical living-donor transplant from his father was performed. A small mass in the father's left kidney was diagnosed as an angiomyolipoma during the pretransplant donor evaluation. During the surgery, the mass was excised and the kidney implanted. One week later, the pathological study revealed the mass to be a clear cell renal carcinoma. After joint discussion, the urologic and nephrologic teams and the family decided to maintain the transplant, managing the patient with monotherapy based on rapamycin and close ultrasound control. To date, 8 years after transplantation, no signs of malignancy have been detected, and renal function is normal. CONCLUSION: This is the first reported pediatric case of a living-donor graft with a small renal carcinoma excised in the operating room. No malignancy has been observed in 8 years of follow-up.

Comparison of MMF efficacy and safety in paediatric vs. adult renal transplantation: subgroup analysis of the randomised, multicentre FDCC trial.

BACKGROUND: Mycophenolate mofetil (MMF) is widely used for immunosuppressive therapy in renal transplantation, but comparative data regarding efficacy and safety in paediatric vs. adult kidney allograft recipients in one and the same study are lacking. METHODS: We therefore performed this subgroup analysis of the FDCC trial, a 12-month, prospective, randomised study, comparing fixed-dose (FD) with concentration-controlled (CC) MMF dosing in paediatric and adult renal transplant recipients. Sixty-two paediatric and 839 adult de novo patients in 19 countries were randomised 1:1 to receive fixed-dose or concentration-controlled MMF therapy in combination with calcineurin inhibitors and corticosteroids. RESULTS: Both patient and allograft survival proved to be excellent in paediatric patients (98.4% and 90.3%) and adults (96.8% and 95.0%). The rates of biopsy-proven acute rejections (BPAR) and treated acute rejection episodes (ARE) were comparable between paediatric (12.9% and 17.7%) and adult patients (15.5% and 20.7%). Transplant function at 12 months post-transplant was similar in paediatric (67.8 ± 45.6 mL/min/1.73 m2;) and adult recipients (64.7 ± 23.3 mL/min/1.73 m2;). Children < 6 years (n = 10) exhibited a numerically higher frequency of leucocytopaenia (20%), diarrhoea (40%) and weight loss (10%) than older children (6-18 years; 5.8%, 28.8% and 1.9%) and adults (16.1%, 24.7% and 1.5%). On the whole, the percentage of patients who experienced adverse events causing interruption of MMF therapy were numerically lower in children (4.8%) than in adults (12.5%). Conclusions. The overall efficacy and tolerability of MMF appear to be comparable between paediatric and adult patients. Further studies are needed to validate these results.

Evolutive study of children with diffuse mesangial sclerosis.

Diffuse mesangial sclerosis (DMS) is a renal disease that usually presents as a nephrotic syndrome. It is characterized by early onset and rapid progression to end-stage renal disease, and can occur as an isolated finding or as part of the Denys-Drash syndrome. The aim of this study was to characterize clinical features and outcomes of DMS in a cohort of children. We retrospectively analyzed all cases of DMS diagnosed in our hospital between 1973 and 2008 and evaluated the progression of the disease in relation to different variables. We studied 14 patients, four with incomplete Denys-Drash syndrome and one with Frasier syndrome. All patients developed renal failure. Eight patients received a renal transplant with no relapse of the disease. Bilateral nephrectomy was performed in nine patients with end-stage renal disease. Seven patients died, with sepsis being the main cause of death. Diffuse mesangial sclerosis must be suspected in a child that presents with early onset proteinuria and/or rapidly progressive renal failure. Karyotype and WT1 gene analysis should be performed because of the predisposition of patients to develop different types of tumors. This nephropathy has a poor prognosis, but the survival rate has improved in the last decade.

Antierythropoietin antibody-induced pure red cell aplasia: posttransplant evolution.

Pure red cell aplasia is a rare complication of recombinant human erythropoietin (rHuEPO) treatment, which physicians should consider once the more frequent causes of hyporegenerative anemia have been excluded. To our knowledge, no pediatric cases have been described. In our patient, cyclosporin A treatment enabled a reduction in the number of transfusions and the risk of hyperimmunization. After transplantation, our patient's hemoglobin level has remained normal and stable.