Renal allograft survival rates in kidneys initially declined for paediatric transplantation.

BACKGROUND: The outcome of organs which have been declined for paediatric recipients is not known. This study aimed to determine the outcome of kidneys initially declined for paediatric recipients and establish renal allograft survival in kidneys that were eventually transplanted. METHODS: Data were obtained from the UK Transplant Registry for all donation after brain death (DBD) kidneys offered and declined to paediatric recipients (< 18 years) in the UK from 2009 to 2014. RESULTS: Eighty-two percent (503/615) of kidneys initially declined for paediatric transplantation were eventually transplanted, 7% (46/615) of kidneys went to paediatric recipients and 62% (384/615) of kidneys went to adult (kidney only) recipients. The remainder were used for multiple organ transplants. In the 46 kidneys that went to paediatric recipients, 1 and 3-year renal allograft survivals were 89% (95% CI 75.8-95.3%) and 82% (95% CI 67.1-90.6%), respectively. In the 384 kidneys given to adult kidney-only recipients, 1 and 3-year renal allograft survivals were 96% (95% CI 93.5-97.6%) and 94% (95% CI 90.7-96.1%), respectively. Eighty-four percent of the 204 children who initially had an offer declined on their behalf were eventually transplanted and have a functioning graft at a median 3-year follow-up. CONCLUSIONS: This study reports acceptable short-term renal allograft survival in kidneys that were initially declined for paediatric recipients and subsequently transplanted. Evidence-based guidelines are required to ensure that the most appropriate kidneys are selected for paediatric recipients.

Lessons learned from the ESPN/ERA-EDTA Registry.

End-stage renal disease (ESRD) in children is a medically challenging condition. Due to its rarity and special features, methodologically sound collaborative studies are required. In 2007, a new European registry of pediatric renal replacement therapy (RRT), the ESPN/ERA-EDTA Registry, was launched. In recent years, the Registry has provided comprehensive data on incidence, prevalence, patient characteristics, RRT modalities, and mortality in pediatric ESRD, along with relevant insights into cardiovascular risk, anemia, nutrition and growth, transplantation outcomes, and rare diseases. In this review, we describe the study design and structure underlying the ESPN/ERA-EDTA Registry, summarize the major research findings from more than 20 publications, and discuss current limitations and the future challenges to overcome.

Anemia in children following renal transplantation-results from the ESPN/ERA-EDTA Registry.

BACKGROUND: Our aim was to determine the prevalence of sub-target hemoglobin (Hb) levels in children with a renal allograft and to identify potential determinants associated with these Hb levels. METHODS: Data from 3669 children with a functioning renal allograft, aged <18 years between 1 January 2000 and 31 December 2012, from 20 European countries were retrieved from the ESPN/ERA-EDTA Registry, providing 16,170 Hb measurements. RESULTS: According to the NKF/KDOQI classification and the UK-NICE guidelines, 49.8 and 7.8% of the patients, respectively, were anemic. Hb levels were strongly associated with graft function, with Hb levels of 12.6 g/dl in children with chronic kidney disease (CKD) stage 1, declining to 10.7 g/dl in children with CKD stage 5 (P < 0.001). Higher Hb levels were associated with the use of tacrolimus compared to ciclosporin (0.14 g/dl; 95% confidence interval 0.02-0.27; P = 0.002). Low Hb levels were associated with an increased risk of graft failure (P = 0.01) or combined graft failure and death (P < 0.01), but not with death alone (not significant). CONCLUSIONS: Anemia is present in a significant proportion of European pediatric kidney transplant recipients and is associated with renal allograft dysfunction and type of immunosuppressants used. In our patient cohort, higher Hb levels were associated with better graft and patient survival and less hypertension.

The effect of timing of the first kidney transplantation on survival in children initiating renal replacement therapy.

BACKGROUND: Controversy exists concerning the timing of the first kidney transplantation for children who need to start renal replacement therapy (RRT). Our aim was to estimate the effect of timing of the first transplantation on patient survival in children, for the first time also taking into account the mortality on dialysis before transplantation. METHODS: We included 2091 patients who started RRT between the age of 3 and 18 years in the period 1988-2007, from 13 European renal registries. A multistate model was used to simulate patient survival assuming (i) pre-emptive transplantation, (ii) transplantation after 1 or 2 years on dialysis and (iii) remaining on dialysis. RESULTS: Over the 20-year period, the highest 8-year survival probabilities were achieved in children transplanted pre-emptively {living donor (LD): 95.9% [95% confidence interval (CI): 93.1-98.8], deceased donor (DD): 95.3% (95% CI: 90.9-99.9)} rather than after 2 years of dialysis [LD: 94.2% (95% CI: 91.6-96.8), DD: 93.4% (95% CI: 91.0-95.9)], although these differences were not statistically significant. CONCLUSIONS: Even after taking mortality on dialysis into account, the potentially negative effect of postponing transplantation for 1 or 2 years was relatively small and not statistically significant. Therefore, if pre-emptive transplantation is not possible, starting RRT with a short period of dialysis and receiving a transplant thereafter seems an acceptable alternative from the perspective of patient survival.

Prevalence and predictors of the sub-target Hb level in children on dialysis.

BACKGROUND: Anaemia is a common and potentially treatable co-morbidity of end-stage renal disease. We aimed to determine the prevalence of the sub-target haemoglobin (Hb) level among European children on dialysis and to identify factors associated with a low Hb level. METHODS: From the European Society for Paediatric Nephrology (ESPN)/European Renal Association-European Dialysis Transplant Association (ERA-EDTA) registry, data were available on 2351 children between 1 month and 18 years of age, totalling 5546 measurements from 19 countries. RESULTS: The mean Hb level was 10.8 g/dL (5th-95th percentiles, 7.4-13.9). Among those above 2 years of age, the mean Hb level was 10.9 g/dL (11.4% below 8.5 g/dL), while it was 10.3 g/dL among those below 2 years (11.2% below 8.0 g/dL). A total of 91.2% of the patients were on an erythropoiesis-stimulating agent (ESA). Hb levels increased with age and were higher in peritoneal dialysis compared with haemodialysis patients. Patients with congenital anomalies of the kidney and urinary tract showed the highest Hb levels, and those with cystic kidney diseases or metabolic disorders the lowest ones. Ferritin levels between 25 and 50 ng/mL were associated with the highest Hb levels. We found a weak inverse association between parathyroid hormone (PTH) and Hb. Whereas standardized blood pressure (BP) was not elevated in patients with above-target Hb, elevated systolic BP z-score was noted in those with sub-target Hb levels. CONCLUSIONS: Sub-target Hb levels remain common in children on dialysis, in spite of virtually all children being treated with ESA; although we cannot exclude under-dosing. Optimal ferritin levels seemed to be slightly lower in children (25-50 ng/mL) than those in adults. Other risk factors for sub-target Hb are dialysis modality and a high PTH level.

Epidemiology of chronic kidney disease in children.

In the past 30 years there have been major improvements in the care of children with chronic kidney disease (CKD). However, most of the available epidemiological data stem from end-stage renal disease (ESRD) registries and information on the earlier stages of pediatric CKD is still limited. The median reported incidence of renal replacement therapy (RRT) in children aged 0-19 years across the world in 2008 was 9 (range: 4-18) [corrected] per million of the age-related population). [corrected] The prevalence of RRT in 2008 ranged from 18 to 100 per million of the age-related population. Congenital disorders, including congenital anomalies of the kidney and urinary tract (CAKUT) and hereditary nephropathies, are responsible for about two thirds of all cases of CKD in developed countries, while acquired causes predominate in developing countries. Children with congenital disorders experience a slower progression of CKD than those with glomerulonephritis, resulting in a lower proportion of CAKUT in the ESRD population compared with less advanced stages of CKD. Most children with ESRD start on dialysis and then receive a transplant. While the survival rate of children with ERSD has improved, it remains about 30 times lower than that of healthy peers. Children now mainly die of cardiovascular causes and infection rather than from renal failure.

Red cell exchange transfusion as a rescue therapy for tacrolimus toxicity in a paediatric renal transplant.

Tacrolimus is a widely used macrolide immunosuppressant that has a narrow therapeutic index and potential side effects including neurotoxicity. A 20-month-old boy with kidney disease secondary to prune belly syndrome variant, managed on peritoneal dialysis, received a deceased donor transplant. Standard immunosuppression was used. There was good early graft function. Post-transplant he developed fungal peritonitis associated with a significant reduction in graft function and was treated with caspofungin and fluconazole. Despite tacrolimus dose reduction he developed a rapid rise in tacrolimus concentration to a maximum of 72 ng/ml with an otherwise unexplained reduction in consciousness. He underwent a single volume exchange transfusion with packed red cells and 4.5% albumin (ratio 2:1). This resulted in immediate reduction of his tacrolimus concentration from 61.8 ng/ml to 35.2 ng/ml. The neurological deficit rapidly resolved. The fungal peritonitis was eradicated. Renal function recovered from a nadir of eGFR <10 ml/min/1.73 m² to a baseline of 30 ml/min/1.73 m². At 30 months post-transplant the child has creatinine of 1.4 mg/dl (eGFR of 31 ml/min/1.73 m²), and is developmentally appropriate with no neurological deficit. Red cell exchange transfusion is a potentially safe and effective way of managing severe and symptomatic tacrolimus toxicity.

Determinants of eGFR at start of renal replacement therapy in paediatric patients.

BACKGROUND: Few studies have investigated the determinants of glomerular filtration rate (GFR) in paediatric patients starting on dialysis or with a transplant. METHODS: Data were collected as part of the European Society of Paediatric Nephrology/European Renal Association-European Dialysis and Transplant Association registry from 14 European countries and referred to incident paediatric patients starting on renal replacement therapy (RRT) between 2002 and 2007 under the age of 18 years. Estimated glomerular filtration rate (eGFR) was calculated using the Schwartz formula. Data were adjusted for age, gender, treatment modality at start, primary cause of renal failure (PRD) and regions in Europe (eGFR(adj)). RESULTS: Median eGFR in the 938 patients starting RRT was 10.4 mL/min/1.73 m(2) (5th and 95th percentile: 4.0-26.9). Twenty-six patients (2.8%), mainly infants with Finnish-type nephropathy, started with eGFR levels >50 mL/min/1.73 m(2). Younger age, female gender, starting on dialysis and having a short time between the first visit to a paediatric nephrologist (PN) and start of RRT were associated with lower eGFR at start of RRT. Gender differences were only present during adolescent age and disappeared when using the same K value for both genders. The various PRDs showed large differences in the rate of decline in eGFR between the first visit to a PN and start of RRT; however, this did not result in differences in eGFR(adj) at start of RRT. CONCLUSIONS: The main determinants of eGFR at start of RRT were age, gender, treatment modality at start, and the time between the first visit to a PN and start of RRT. Research is needed to determine the consequences of these differences.

Clinical practice: Diagnosis and management of Henoch-Schönlein purpura.

Henoch-Schönlein purpura (HSP) is the most common vasculitis of childhood. In this review, the main clinical features and complications are described. Although most features are self-limiting, renal disease is the most likely to result in long-term morbidity. Treatment of HSP nephritis is controversial, and the evidence for both prevention and treatment of established disease is reviewed. Follow-up for children presenting with HSP should be for at least 6 months and should include regular urine testing for proteinuria and haematuria and a blood pressure measurement. Women with a history of HSP during childhood are at increased risk of complications (such as proteinuria and hypertension) during pregnancy and should be monitored closely. This paper describes current practice with regard to investigation and management and proposes a practical care pathway of the management of a child with HSP.

Kawasaki disease: a prospective population survey in the UK and Ireland from 2013 to 2015.

OBJECTIVE: Kawasaki disease (KD) is an increasingly common vasculitis with risk of coronary artery aneurysms (CAAs). The last UK survey was in 1990, whereas current epidemiology, treatment patterns and complication rates are unknown. The aim of this study was to address this knowledge gap. METHODS: A British Paediatric Surveillance Unit survey in the UK and Ireland from 1 January 2013 to 28 February 2015 ascertained demographics, ethnicity, seasonal incidence, treatment and complication rates. RESULTS: 553 cases were notified: 389 had complete KD, 46 had atypical KD and 116 had incomplete KD; 2 were diagnosed at postmortem with an incidence of 4.55/100 000 children under 5 years, with a male to female ratio of 1.5:1 and a median age of 2.7 years (2.5 months-15 years). Presentation was highest in January and in rural areas. Most were white (64%), and Chinese and Japanese Asians were over-represented as were black African or African mixed-race children. 94% received intravenous immunoglobulin (IVIG). The overall CAA rate was 19%, and all-cardiac complications affected 28%. Those with CAA received IVIG later than in those without (median 10 days vs 7 days). Those under 1 year had fewer symptoms, but the highest CAA rate (39%). Overall 8 of 512 cases (1.6%) had giant CAA, and 4 of 86 cases (5%) under 1 year of age developed giant CAA. Mortality from KD was 0.36%. CONCLUSIONS: The UK and Ireland incidence of KD has increased and is more frequently seen in winter and rural areas. Delayed IVIG treatment is associated with CAA, suggesting earlier and adjunctive primary treatment might reduce complications to prevent CAA, particularly in the very young.

A phase I trial of epstein-barr virus gp350 vaccine for children with chronic kidney disease awaiting transplantation.

BACKGROUND.: Vaccination against Epstein-Barr virus (EBV), inducing an antibody response to the envelope glycoprotein gp350, might protect EBV-negative children with chronic kidney disease from lymphoproliferative disease after transplantation. METHODS.: A phase I trial recruited children with chronic kidney disease to two successive cohorts given three injections of 12.5 microg (n=6) and 25 microg (n=10) recombinant gp350/alhydrogel vaccine over 6 to 8 weeks. RESULTS.: One in each cohort acquired wild EBV before the week 28 evaluation. Both doses were similarly immunogenic, inducing an IgG response in all 13 evaluable patients. Neutralizing antibodies were detected in four recipients (1/4 in the 12.5 microg and 3/9 in the 25 microg cohort). Median time from first vaccination to transplantation was 24 weeks. Immune responses declined rapidly and were unlikely to affect posttransplant events. DISCUSSION.: The vaccine was immunogenic but a prolonged vaccine schedule up to time of transplantation or improved adjuvants are required in future trials to reduce posttransplant EBV load and risk of lymphoproliferative disease.

Prognosis, treatment and outcome of childhood mesangiocapillary (membranoproliferative) glomerulonephritis.

BACKGROUND: Prognostic factors and outcome are incompletely known in childhood mesangiocapillary glomerulonephritis (MCGN). This study aimed to correlate renal outcome with clinical and histopathological variables. METHODS: We conducted a two-centre retrospective analysis of children with MCGN. RESULTS: Fifty-three children presented at a mean age of 8.8 years (range: 13 months-15 years). They were followed for a median of 3.5 years (range: 0-17 years). Histological classification identified 31 type 1, 14 type 2, two type 3 and six undetermined type. Mean renal survival [time to end-stage renal failure (ESRF)] was projected to be 12.2 years [confidence interval (CI): 9.7-14.6 years]. Five and 10 year renal survival was 92% (CI: 88-100%) and 83% (CI: 74-92%), respectively. Those with nephrotic syndrome at presentation had mean renal survival of 8.9 years (CI: 7.1-10.7 years) vs 13.6 years for those without (CI: 10.8-16.5 years) (P = 0.047). The mean estimated glomerular filtration rate (eGFR) at 1 year in those who progressed to ESRF was 52 vs 98 ml/min/1.73 m2 in those who did not (P < 0.001). Chronic damage scored on the first biopsy in 31 children (one centre) was positively associated with adverse renal outcome at 5 years: <20% was associated with 100% and > or =20% with 71% 5-year renal survival (P = 0.006). In 29 children treated with steroid there was a higher proportion (76%) with reduced eGFR at presentation and a significantly higher incidence of nephrotic syndrome (P = 0.002) and hypertension (P = 0.037). There were no significant differences in outcome eGFR, hypertension or proteinuria. CONCLUSIONS: Nephrotic syndrome at presentation and subnormal eGFR at 1 year were adverse features. The finding that structural disease at onset predicted poor renal outcome at 5 years has implications for the design of therapeutic trials. Treatment of MCGN was variable and not evidence-based.