Marcus Weitz

Prophylactic eculizumab prior to kidney transplantation for atypical hemolytic uremic syndrome

Atypical hemolytic uremic syndrome (aHUS) in childhood is a rare disease associated with high morbidity and mortality. Most cases progress to end-stage renal failure. In approximately 50% of affected patients, mutations in genes encoding complement proteins are causative of the impairment in the regulation of the complement alternative pathway. This leads to deficient host cell protection and inappropriate complement activation on platelets and endothelial cells, particularly in the kidneys. Complement factor H (FH) heterozygosity induces unregulated activation of the membrane attack complex (MAC) C5b-9. Present therapeutic strategies for aHUS include lifelong plasmapheresis and renal dialysis. Unfortunately, kidney transplantation is frequently an unsatisfactory intervention due to the high rate of post-transplantation HUS recurrence, particularly in patients with FH mutation. Combined liver–kidney transplantation is also associated with poor outcome, mostly as a result of premature liver failure secondary to uncontrolled complement activation. Eculizumab is a complement C5 antibody that inhibits complement factor 5a (C5a) and the formation of the MAC. Thus, this antibody may be a promising new agent for patients with an aHUS undergoing kidney transplantation. We present the first case of a young patient with aHUS who received eculizumab as prophylactic treatment prior to a successful kidney transplantation.

Standardized multilevel transition program: Does it affect renal transplant outcome?

The transfer of renal transplant patients from pediatric to adult care is a crucial step with a high risk of subsequent graft loss. Therefore, the transition should be a thoroughly planned, well‐designed and multidisciplinary process focused on the individual patient. Our pediatric nephrology department introduced a structured step‐by‐step transition program supported by a multidisciplinary team of health professionals. The purpose of our study was to determine the effects of the transition program on eGFR and number of ARs in comparison to a group without a transition program at one and three yr after transfer. We conducted a single‐center retrospective cohort study of renal transplant patients prior to and after the introduction of the transition program. Multiple regression analysis revealed a significantly lower decline of eGFR in the group with transition program (−11.3 ± 44 mL/min/1.73 m2) compared to the group without transition program (−28.4 ± 33 mL/min/1.73 m2) at three yr after transfer. The number of AR episodes significantly decreased from 34.6% in the group without transition program to 9.1% in the group with transition program. The standardized multilevel transition program seems to have significant positive effects on eGFR and number of AR episodes in renal transplant patients.

Primary non-surgical management of unilateral ureteropelvic junction obstruction in children: a systematic review

Ureteropelvic junction obstruction (UPJO) is the most common obstructive uropathy and its optimal management remains controversial. However, there is a current trend towards non-surgical management. We aimed to determine the effects of the non-surgical management in children with unilateral UPJO. For a systematic review, we searched MEDLINE, EMBASE, CENTRAL, clinical trials registries, and selected conference proceedings for eligible studies. Any type of study reporting the outcomes renal function, secondary surgical intervention, drainage pattern or hydronephrosis of non-surgical management in children with unilateral UPJO was included. Data from 20 studies were extracted and evaluated by two independent authors. The pooled prevalence was 21% for split renal function deterioration, 27.9% for secondary surgical intervention, 3.2% for progressive hydronephrosis, and 82.2% for improved drainage pattern. Not all patients with surgical intervention regained split renal function from enrolment. Renal imaging methods did not strongly correlate with each other. Many studies had to be excluded because of a lack of detection of an obstruction or mixed populations with bilateral UPJO or other uropathies. The variable definitions of UPJO, different criteria for surgical intervention, incongruity of management protocols, and the imprecise reporting of outcomes were limiting factors in the comparability of the results, leading to heterogeneity in meta-analyses. Although the available evidence cannot recommend or refute the current non-surgical management, the systematic review clarifies aspects of the ongoing controversy by providing realistic estimates for non-surgical management in children with unilateral UPJO. Additionally, it reveals unclear potential risks, particularly for long-term outcomes, which were rarely reported.

Membranoproliferative glomerulonephritis and C3 glomerulopathy in children: change in treatment modality? A report of a case series

Abstract Background Membranoproliferative glomerulonephritis (MPGN) with immune complexes and C3 glomerulopathy (C3G) in children are rare and have a variable outcome, with some patients progressing to end-stage renal disease (ESRD). Mutations in genes encoding regulatory proteins of the alternative complement pathway and of complement C3 (C3) have been identified as concausative factors. Methods Three children with MPGN type I, four with C3G, i.e. three with C3 glomerulonephritis (C3GN) and one with dense deposit disease (DDD), were followed. Clinical, autoimmune data, histological characteristics, estimated glomerular filtration rate (eGFR), proteinuria, serum C3, genetic and biochemical analysis were assessed. Results The median age at onset was 7.3 years and the median eGFR was 72 mL/min/1.73 m2. Six children had marked proteinuria. All were treated with renin–angiotensin–aldosterone system (RAAS) blockers. Three were given one or more immunosuppressive drugs and two eculizumab. At the last median follow-up of 9 years after diagnosis, three children had normal eGFR and no or mild proteinuria on RAAS blockers only. Among four patients without remission of proteinuria, genetic analysis revealed mutations in complement regulator proteins of the alternative pathway. None of the three patients with immunosuppressive treatment achieved partial or complete remission of proteinuria and two progressed to ESRD and renal transplantation. Two patients treated with eculizumab revealed relevant decreases in proteinuria. Conclusions In children with MPGN type I and C3G, the outcomes of renal function and response to treatment modality show great variability independent from histological diagnosis at disease onset. In case of severe clinical presentation at disease onset, early genetic and biochemical analysis of the alternative pathway dysregulation is recommended. Treatment with eculizumab appears to be an option to slow disease progression in single cases.

Balancing competing needs in kidney transplantation: does an allocation system prioritizing children affect the renal transplant function?

Children often merit priority in access to deceased donor kidneys by organ‐sharing organizations. We report the impact of the new Swiss Organ Allocation System (SOAS) introduced in 2007, offering all kidney allografts from deceased donors <60 years preferentially to children. The retrospective cohort study included all paediatric transplant patients (<20 years of age) before (n = 19) and after (n = 32) the new SOAS (from 2001 to 2014). Estimated glomerular filtration rate (eGFR), urine protein‐to‐creatinine ratio (UPC), need for antihypertensive medication, waiting times to kidney transplantation (KTX), number of pre‐emptive transplantations and rejections, and the proportion of living donor transplants were considered as outcome parameters. Patients after the new SOAS had significantly better eGFRs 2 years after KTX (Mean Difference, MD = 25.7 ml/min/1.73 m2, P = 0.025), lower UPC ratios (Median Difference, MeD = −14.5 g/mol, P = 0.004), decreased waiting times to KTX (MeD = −97 days, P = 0.021) and a higher proportion of pre‐emptive transplantations (Odds Ratio = 9.4, 95% CI = 1.1–80.3, P = 0.018), while the need for antihypertensive medication, number of rejections and living donor transplantations remained stable. The new SOAS is associated with improved short‐term clinical outcomes and more rapid access to KTX. Despite lacking long‐term research, the study results should encourage other policy makers to adopt the SOAS approach.