Chronic kidney disease (CKD) is a major health problem worldwide. Although relatively uncommon in children, it can be a devastating illness with many long-term consequences. CKD presents unique features in childhood and may be considered, at least in part, as a stand-alone nosologic entity. Moreover, some typical features of paediatric CKD, such as the disease aetiology or cardiovascular complications, will not only influence the child's health, but also have long-term impact on the life of the adult that they will become. In this review we will focus on the unique issues of paediatric CKD, in terms of aetiology, clinical features and treatment. In addition, we will discuss factors related to CKD that start during childhood and require appropriate treatments in order to optimize health outcomes and transition to nephrologist management in adult life.

These recommendations are endorsed by the Italian Society of Pediatric Nephrology. They can also be a tool of comparison with other existing guidelines in issues in which much controversy still exists.

AimOur aim was to update the recommendations for the diagnosis, treatment and follow‐up of the first febrile urinary tract infection in young children, which were endorsed in 2012 by the Italian Society of Pediatric Nephrology.MethodsThe Italian recommendations were revised on the basis of a review of the literature published from 2012 to October 2018. We also carried out an ad hoc evaluation of the risk factors to identify children with high‐grade vesicoureteral reflux or renal scarring, which were published in the previous recommendations. When evidence was not available, the working group held extensive discussions, during various meetings and through email exchanges.ResultsFour major modifications have been introduced. The method for collecting urine for culture and its interpretation has been re‐evaluated. We have reformulated the algorithm that guides clinical decisions to proceed with voiding cystourethrography. The suggested antibiotics have been revised, and we have recommended further restrictions of the use of antibiotic prophylaxis.ConclusionThese updated recommendations have now been endorsed by the Italian Society of Pediatric Nephrology and the Italian Society for Pediatric Infectivology. They can also be used to compare other recommendations that are available, as a worldwide consensus in this area is still lacking.

The critical role of genetic and epigenetic factors in the pathogenesis of kidney disorders is gradually becoming clear, and the need for disease models that recapitulate human kidney disorders in a personalized manner is paramount. In this study, we describe a method to select and amplify renal progenitor cultures from the urine of patients with kidney disorders. Urine-derived human renal progenitors exhibited phenotype and functional properties identical to those purified from kidney tissue, including the capacity to differentiate into tubular cells and podocytes, as demonstrated by confocal microscopy, Western blot analysis of podocyte-specific proteins, and scanning electron microscopy. Lineage tracing studies performed with conditional transgenic mice, in which podocytes are irreversibly tagged upon tamoxifen treatment (NPHS2.iCreER;mT/mG), that were subjected to doxorubicin nephropathy demonstrated that renal progenitors are the only urinary cell population that can be amplified in longterm culture. To validate the use of these cells for personalized modeling of kidney disorders, renal progenitors were obtained from (1) the urine of children with nephrotic syndrome and carrying potentially pathogenic mutations in genes encoding for podocyte proteins and (2) the urine of children without genetic alterations, as validated by next-generation sequencing. Renal progenitors obtained from patients carrying pathogenic mutations generated podocytes that exhibited an abnormal cytoskeleton structure and functional abnormalities compared with those obtained from patients with proteinuria but without genetic mutations. The results of this study demonstrate that urine-derived patient-specific renal progenitor cultures may be an innovative research tool for modeling of genetic kidney disorders. 26: 196126: -197426: , 201526: . doi: 10.1681 The incidence of AKI and CKD is rising and reaching epidemic proportions. 1 In patients with CKD, the progressive decline in renal function is multifactorial and attributable to a variety of mechanisms. 2 In particular, the critical role of genetic factors in the etiology, pathogenesis, and progression of many renal disorders is gradually becoming clear, especially in children. 3 Indeed, the advent of high-throughput sequencing techniques has fostered the identification of novel causative genes and allows the continuous discovery of genetic variants of unknown clinical significance, often raising the problem of the functional testing of their pathogenic role. 4 However, emerging evidence suggests that influence of the J Am Soc Nephrol

Primary distal renal tubular acidosis is a rare genetic disease. Mutations in SLC4A1, ATP6V0A4, and ATP6V1B1 genes have been described as the cause of the disease, transmitted as either an autosomal dominant or recessive trait. Particular clinical features, such as sensorineural hearing loss, have been mainly described in association with mutations in one gene instead of the others. Nevertheless, the diagnosis of distal renal tubular acidosis is essentially based on clinical and laboratory findings, and the series of patients described so far are usually represented by small cohorts. Therefore, a strict genotype-phenotype correlation is still lacking, and questions about whether clinical and laboratory data should direct the genetic analysis remain open. Here, we applied next-generation sequencing in 89 patients with a clinical diagnosis of distal renal tubular acidosis, analyzing the prevalence of genetic defects in SLC4A1, ATP6V0A4, and ATP6V1B1 genes and the clinical phenotype. A genetic cause was determined in 71.9% of cases. In our group of sporadic cases, clinical features, including sensorineural hearing loss, are not specific indicators of the causal underlying gene. Mutations in the ATP6V0A4 gene are quite as frequent as mutations in ATP6V1B1 in patients with recessive disease. Chronic kidney disease was frequent in patients with a long history of the disease. Thus, our results suggest that when distal renal tubular acidosis is suspected, complete genetic testing could be considered, irrespective of the clinical phenotype of the patient