Is Cystatin C a promising marker of renal function, at birth, in neonates prenatally diagnosed with congenital kidney anomalies?

Assessment of neonatal renal function remains a challenge. This study by Paloma et al. suggest that low-molecular weight proteins may indeed serve as promising markers of renal function at birth and in neonates prenatally diagnosed with congenital kidney anomalie

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 m(2) , 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

Congenital anomalies of the kidney and urinary tract (CAKUT): from the prenatal diagnosis to patient's care and prognosis

Congenital kidney malformations of the kidney and urinary tract (CAKUT) include a large spectrum of diseases occurring subsequently to a misdevelopement in kidney development during gestation. The majority of theses diseases are prenatally diagnosed, for this reason accurate diagnosis is needed for counseling to parents and to decide of the better management at birth. Since 2008, we create a database to establish a cohort of neonates diagnosed with CAKUT to include prospectively pre and postnatal data to improve knowledge in these diseases. CAKUT are the most frequent cause of end stage renal disease during childhood. The wide variability of these pathologies is due to the complexity of kidney development. CAKUT may be secondary to an anomaly of tissue interaction at an early stage or to a modification of a molecular pathway at different steps of nephrogenesis. Hence, nephrogenesis may lead in the majority of the cases to low renal endowment similarly to what is observed in premature and neonates borne small for age. With the first nephrons, primitive renal function appears and small amount of urine began to be produced at 10 weeks of gestation and increased progressively to reach a mature glomerular filtration rate at the age on one year. Since renal function at birth is immature, its evaluation is chief to discriminate among neonates, those who may present a possible low renal endowment and subsequently an increased risk of renal progression. However in this population, the evaluation of renal function is challenging, because of the difficulty to validate potential renal markers with a gold standard. In these work, we proposed to present a new approach for CAKUT disease with the measure of renal function since birth using Cystatin C (CysC), a renal marker, recognized to be sensible for neonates. Reference interval of Cystatin C for this age is proposed in the literature and we validate in our center a reference interval for CysC in normal term babies. When comparing CysC values of this control group, to neonates from our cohort with kidney malformation, we showed that neonates with bilateral kidney malformation had a statistically CysC increased value compared to the control group. We proposed a cut-off value for Cystatin C, above which it may indicate an increased risk to present impaired renal endowment. The majority of renal and urinary tract malformation will be revealed prenatally and the most frequent presentation is the detection on the ultrasounds of an antenatal pelvic dilatation. Many authors have proposed guidelines for the management at birth of antenatal pelvic dilatation with variable cut-off's of posterior anterior diameter. These guidelines are important to identify neonates at risk of severe obstruction or who need an imaging evaluation to rule out vesico-ureteral reflux and avoid subsequent infections and renal scars. For the future, the target will be to succeed to delay renal function. With early and multidisciplinary management of these neonates since the last decade, we already noticed a delay in renal function progression, however there is a strong need to identify predictor factors to improve long term prognosis. Indeed renal endowment increased the risk to present renal progression but also hypertension and in adulthood cardio-vascular diseases. For this purpose, we followed, our cohort of neonates with CAKUT, two years after birth to analyzed predictors of renal function progression using CysC and creatinine as markers for renal function. We found that the bilateralism of the renal malformation and or the relative renal function asymmetry detected by the initial scintigraphy were factors of renal progression. Another approach, proposed to decrease renal function progression is to target the treatment of proteinuria with ACE inhibitors. Finally, to accurately assess neonatal renal function, the validation of Cystatin C with a gold standard will be essential. Likewise, neonates with CAKUT, premature and small for age neonates, because of possible impaired renal endowment will benefit of a useful clinical tool for the measure of renal function, often undeerdiagnosed in thie population

Antibody‐mediated rejection after kidney transplantation in children; therapy challenges and future potential treatments

Antibody-mediated rejection (AMR) remains one of the most critical problems in renal transplantation, with a significant impact on patient and graft survival. In the United States, no treatment has received FDA approval jet. Studies about treatments of AMR remain controversial, limited by the absence of a gold standard and the difficulty in creating large, multi-center studies. These limitations emerge even more in pediatric transplantation because of the limited number of pediatric studies and the occasional use of some therapies with unknown and poorly documented side effects. The lack of recommendations and the unsharp definition of different forms of AMR contribute to the challenging management of the therapy by pediatric nephrologists. In an attempt to help clinicians involved in the care of renal transplanted children affected by an AMR, we rely on the latest recommendations of the Transplantation Society (TTS) for the classification and treatment of AMR to describe treatments available today and potential new treatments with a particular focus on the pediatric population

Hématurie et protéinurie chez l'enfant : attitude pratique

Hematuria and proteinuria are often the first signs of potentially severe kidney diseases. Investigations of a child with proteinuria +/- hematuria should start at the primary care physician office, and will permit to rapidly identify the most serious kidney diseases, such as the glomerulonephritis, but also to avoid excessive and costly investigations in patients with a benign condition such as orthostatic proteinuria. Isolated microscopic hematuria is also relatively frequently found during routine pediatric office visit. Secondary to a glomerulonephritis, it is often associated with proteinuria. Urologic causes should be excluded in case of isolated microscopic or macroscopic hematuria

Hypophosphatémies de causes rares : approche diagnostique

Hypophosphatemia is common and may be overlooked due to its asymptomatic nature or non-specific symptoms. Two main mechanisms are at its origin: a shift towards the intracellular sector and an increase in urinary phosphate excretion. A measurement of the urinary phosphate reabsorption threshold allows a diagnostic orientation. Alongside common forms of parathyroid hormone-dependent hypophosphatemia, one should not ignore rare FGF23-mediated forms, in particular X-linked hypophosphatemic rickets. The treatment, above all etiological, also includes the administration of phosphate and, in the event of an excess of FGF23, supplementation with calcitriol. In cases of oncogenic osteomalacia and X-linked hypophosphatemic rickets, the use of burosumab, an anti-FGF23 antibody, must be considered.L’hypophosphatémie est fréquente. Pourtant, elle peut parfois être méconnue de par son caractère asymptomatique ou ses symptômes non spécifiques. Deux grands mécanismes sont à son origine : un shift vers le secteur intracellulaire et une augmentation de l’excrétion urinaire de phosphate. Une mesure du seuil de réabsorption urinaire de phosphate permet une orientation diagnostique. À côté de formes communes d’hypophosphatémies parathormone-dépendantes, il ne faut pas méconnaître des formes rares FGF23 médiées, en particulier le rachitisme hypophosphatémique lié à l’X. Le traitement, avant tout étiologique comporte aussi l’administration de phosphate et lors d’un excès de FGF23, une supplémentation en calcitriol. En cas d’ostéomalacie oncogénique et de rachitisme hypophosphatémique lié à l’X, l’emploi de burosumab, anticorps anti-FGF23, doit être considéré

Enurésies et troubles mictionnels diurnes chez l'enfant

Nocturnal enuresis is a common problem seen by the primary care physician. It is mandatory to distinguish between children having monosymptomatic nocturnal enuresis with normal daytime voiding habits and patients having polysymptomatic bed wetting (associated with urgency, frequency, or other signs of unstable bladder). Investigations and treatment of polysymptomatic enuresis are different than treatment of monosymptomatic nocturnal enuresis. A thorough and thoughtful history of voiding pattern is important to separate urge syndrome from organic causes of enuresis. Management of patients who have urge syndrome include general advices like regular voiding routine, physiotherapy, anticholinergic medication and prevention or treatment of urinary tract infections. If the nocturnal enuresis persists after the control of the voiding dysfunctions, treatment of nocturnal enuresis must be undertaken

Is Cystatin C a promising marker of renal function, at birth, in neonates prenatally diagnosed with congenital kidney anomalies?

Despite the increased prenatal diagnosis of congenital abnormalities of the kidney and urinary tract (CAKUT), no reliable renal marker for glomerular filtration rate (GFR) has been validated yet in neonates. Cystatin C (CysC) is specific to the neonate and is proposed as a sensitive marker for this population. The aims of the study were first to define a reference interval in our center of CysC at birth in normal term babies and assess CysC as a marker of GFR in a group of term neonates prenatally diagnosed with CAKUT compared to controls