Publications by authors named "Pierre Cochat"

202 Publications

[Interferent RNA treatment: Example of primary hyperoxaluria].

Nephrol Ther 2021 Apr;17S:S23-S26

Centre de référence des maladies rénales rares, hôpital Femme-Mère-Enfant, 59 boulevard Pinel, 69677 Bron cedex, France; Service de néphrologie rhumatologie dermatologie pédiatriques, hôpital Femme-Mère-Enfant, 59 boulevard Pinel, 69677 Bron cedex, France; Université Claude-Bernard Lyon-1, 8, avenue Rockefeller, 69008 Lyon, France.

Primary hyperoxalurias are rare disease with autosomal recessive inheritance; they often lead to kidney failure and can lead to life-threatening conditions, especially in early onset forms. There are three types, responding to distinct enzyme deficits. Type 1 represents 85% of cases and results from an enzyme deficiency (alanine-glyoxylate aminotransferase) in the peroxisomes of the liver, causing hyperoxaluria leading to urolithiasis with or without nephrocalcinosis. As glomerular filtration decreases, a systemic overload appears and spares no organ. Treatment has hitherto been based on combined liver and kidney transplantation, with significant mortality and morbidity. The recent introduction of interfering RNA treatments opens up new perspectives. By blocking an enzymatic synthesis (glycolate oxidase or lacticodehydrogenase a) upstream of the deficit that causes the disease, oxaluria normalizes and the tolerance of the drug (administered by injection every 1 to 3 months) is good. This strategy will help prevent kidney failure in patients treated early and avoid liver transplantation in those who are diagnosed at an advanced stage of kidney failure.
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http://dx.doi.org/10.1016/j.nephro.2020.02.002DOI Listing
April 2021

Lumasiran, an RNAi Therapeutic for Primary Hyperoxaluria Type 1.

N Engl J Med 2021 04;384(13):1216-1226

From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.).

Background: Primary hyperoxaluria type 1 (PH1) is a rare genetic disease caused by hepatic overproduction of oxalate that leads to kidney stones, nephrocalcinosis, kidney failure, and systemic oxalosis. Lumasiran, an investigational RNA interference (RNAi) therapeutic agent, reduces hepatic oxalate production by targeting glycolate oxidase.

Methods: In this double-blind, phase 3 trial, we randomly assigned (in a 2:1 ratio) patients with PH1 who were 6 years of age or older to receive subcutaneous lumasiran or placebo for 6 months (with doses given at baseline and at months 1, 2, 3, and 6). The primary end point was the percent change in 24-hour urinary oxalate excretion from baseline to month 6 (mean percent change across months 3 through 6). Secondary end points included the percent change in the plasma oxalate level from baseline to month 6 (mean percent change across months 3 through 6) and the percentage of patients with 24-hour urinary oxalate excretion no higher than 1.5 times the upper limit of the normal range at month 6.

Results: A total of 39 patients underwent randomization; 26 were assigned to the lumasiran group and 13 to the placebo group. The least-squares mean difference in the change in 24-hour urinary oxalate excretion (lumasiran minus placebo) was -53.5 percentage points (P<0.001), with a reduction in the lumasiran group of 65.4% and an effect seen as early as month 1. The between-group differences for all hierarchically tested secondary end points were significant. The difference in the percent change in the plasma oxalate level (lumasiran minus placebo) was -39.5 percentage points (P<0.001). In the lumasiran group, 84% of patients had 24-hour urinary oxalate excretion no higher than 1.5 times the upper limit of the normal range at month 6, as compared with 0% in the placebo group (P<0.001). Mild, transient injection-site reactions were reported in 38% of lumasiran-treated patients.

Conclusions: Lumasiran reduced urinary oxalate excretion, the cause of progressive kidney failure in PH1. The majority of patients who received lumasiran had normal or near-normal levels after 6 months of treatment. (Funded by Alnylam Pharmaceuticals; ILLUMINATE-A ClinicalTrials.gov number, NCT03681184.).
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http://dx.doi.org/10.1056/NEJMoa2021712DOI Listing
April 2021

Living well with kidney disease.

Pediatr Nephrol 2021 May 1;36(5):1035-1036. Epub 2021 Mar 1.

Department of Pediatrics, University of Puerto Rico, Medical Sciences Campus, PO Box 365067, San Juan, 00936-5067, Puerto Rico.

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http://dx.doi.org/10.1007/s00467-021-05011-0DOI Listing
May 2021

Plasma oxalate and eGFR are correlated in primary hyperoxaluria patients with maintained kidney function-data from three placebo-controlled studies.

Pediatr Nephrol 2021 Jan 30. Epub 2021 Jan 30.

OxThera Intellectual Property AB, Stockholm, Sweden.

Background: In patients with primary hyperoxaluria (PH), endogenous oxalate overproduction increases urinary oxalate excretion, leading to compromised kidney function and often kidney failure. Highly elevated plasma oxalate (Pox) is associated with systemic oxalate deposition in patients with PH and severe chronic kidney disease (CKD). The relationship between Pox and estimated glomerular filtration rate (eGFR) in patients with preserved kidney function, however, is not well established. Our analysis aimed to investigate a potential correlation between these parameters in PH patients from three randomized, placebo-controlled trials (studies OC3-DB-01, OC3-DB-02, and OC5-DB-01).

Methods: Baseline data from patients with a PH diagnosis (type 1, 2, or 3) and eGFR > 40 mL/min/1.73 m were analyzed for a correlation between eGFR and Pox using Spearman's rank and Pearson's correlation coefficients. Data were analyzed by individual study and additionally were pooled for Studies OC3-DB-02 and OC5-DB-01 in which the same Pox assay was used.

Results: A total of 106 patients were analyzed. A statistically significant inverse Spearman's correlation between eGFR and Pox was observed across all analyses; correlation coefficients were - 0.44 in study OC3-DB-01, - 0.55 in study OC3-DB-02, - 0.51 in study OC5-DB-01, and - 0.49 in the pooled studies (p < 0.0064).

Conclusions: Baseline evaluations showed a moderate and statistically significant inverse correlation between eGFR and Pox in patients with PH already at early stages of CKD (stages 1-3b), demonstrating that a correlation is present before substantial loss in kidney function occurs.
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http://dx.doi.org/10.1007/s00467-020-04894-9DOI Listing
January 2021

Transplantation for Primary Hyperoxaluria Type 1: Designing New Strategies in the Era of Promising Therapeutic Perspectives.

Kidney Int Rep 2020 Dec 24;5(12):2136-2145. Epub 2020 Sep 24.

Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium.

Primary hyperoxaluria type 1 (PH1) is an autosomal recessive disease caused by the functional defect of alanine-glyoxylate aminotransferase that results in the overproduction of oxalate. It can be devastating especially for kidneys, leading to end-stage renal disease (ESRD) during the first 2 to 3 decades of life in most patients. Consequently, many PH1 patients need kidney transplantation. However, because PH1 is caused by a liver enzyme deficiency, the only cure of the metabolic defect is liver transplantation. Thus, current transplant strategies to treat PH1 patients with ESRD include dual liver-kidney transplantation. However, the morbidity and mortality associated with liver transplantation make these strategies far from optimal. Fortunately, a therapeutic revolution is looming. Indeed, innovative drugs are being currently tested in clinical trials, and preliminary data show impressive efficacy to reduce the hepatic overproduction of oxalate. Hopefully, with these therapies, liver transplantation will no longer be necessary. However, some patients with progressing renal disease or those who will be diagnosed with PH1 at an advanced stage of chronic kidney disease will ultimately need kidney transplantation. Here we review the current knowledge on this subject and discuss the future of kidney transplant management in PH1 patients in the era of novel therapies.
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http://dx.doi.org/10.1016/j.ekir.2020.09.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7710835PMC
December 2020

Long-term outcomes of peritoneal dialysis started in infants below 6 months of age: An experience from two tertiary centres.

Nephrol Ther 2020 Dec 8;16(7):424-430. Epub 2020 Nov 8.

Centre de référence des maladies rénales rares, hôpital femme-mère-enfant, hospices civils de Lyon, 59, boulevard Pinel, 69677 Bron cedex, France. Electronic address:

Background: Little data are available for infants who started renal replacement therapy before 6 months of age. Because of extra-renal comorbidities and uncertain outcomes, whether renal replacement therapy in neonates is justified remains debatable.

Methods: We performed a retrospective analysis of all patients who began chronic peritoneal dialysis below 6 months between 2007 and 2017 in two tertiary centres. Results are presented as median (min;max).

Results: Seventeen patients (10 boys) were included (8 prenatal diagnoses, 6 premies), with the following diagnoses: congenital anomalies of kidney and urinary tract (n=9), oxalosis (n=5), congenital nephrotic syndrome (n=2) and renal vein thrombosis (n=1). Five patients had associated comorbidities. At peritoneal dialysis initiation, age was 2.6 (0.1;5.9) months, height-standard deviation score (SDS) -1.3 (-5.7;1.6) and weight-SDS -1.4 (-3.6;0.6). Peritoneal dialysis duration was 12 (2;32) months, and at peritoneal dialysis discontinuation height-SDS was -1.0 (-4.3;0.7) weight-SDS -0.7 (-3.2;0.2), parathyroid hormone 123 (44;1540) ng/L, and hemoglobin 110 (73;174) g/L. During the first 6 months of peritoneal dialysis, the median time of hospitalisation stay was 69 (15;182) days. Ten patients presented a total of 27 peritonitis episodes. Reasons for peritoneal dialysis discontinuation were switch to hemodialysis (n=6), transplantation (n=6), recovery of renal function (n=2) and death (n=1). After a follow-up of 4.3 (1.7;10.3) years, 12 patients were transplanted, 2 patients were still on peritoneal dialysis, 2 patients were dialysis free with severe chronic kidney disease and 1 patient had died. Seven patients displayed neurodevelopmental delay, of whom five needed special schooling.

Conclusion: We confirm that most infants starting peritoneal dialysis before 6 months of age will be successfully transplanted and will have a favourable growth outcome. Their quality of life will be impacted by recurrent hospitalisations and neurodevelopmental delay is frequent.
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http://dx.doi.org/10.1016/j.nephro.2020.08.002DOI Listing
December 2020

Comparison of iohexol plasma clearance formulas vs. inulin urinary clearance for measuring glomerular filtration rate.

Clin Chem Lab Med 2021 Feb 19;59(3):571-579. Epub 2020 Oct 19.

Néphrologie, Dialyse, Hypertension et Exploration Fonctionnelle Rénale, Hôpital Edouard Herriot, Hospices Civils de Lyon, Lyon, France.

Objectives: The one-compartment iohexol plasma clearance has been proposed as a reliable alternative to renal inulin clearance. However, this method's performance depends on the formula used to calculate glomerular filtration rate (GFR). This study reports on performance comparisons between various mathematical formulas proposed for iohexol plasma clearance vs. inulin urinary clearance.

Methods: GFR was simultaneously determined by inulin and iohexol clearance in 144 participants (age: 10-84 years; glomerular filtration rate: 15-169 mL/min/1.73 m). A retrospective cross-sectional study evaluated the performance of four formulas proposed to calculate plasma iohexol clearance (Brøchner-Mortensen, Fleming et al., Jødal-Brøchner-Mortensen, and Ng-Schwartz-Munoz). The performance of each formula was assessed using bias, precision (standard deviation of the bias), accuracy (percentage iohexol within 5, 10, and 15%), root mean square error, and concordance correlation coefficient vs. renal inulin clearance as reference.

Results: Regarding accuracy, there was no difference in root mean square error (RMSE), P, P, or P between the four formulas. The four concordance correlation coefficients (CCC) between the value from each formula and in-GFR were high and not significantly different. At in-GFR ≥90 mL/min/1.73 m, Ng-Schwartz-Munoz formula performed slightly better than other formulas regarding median bias (-0.5; 95% CI [-3.0 to 2.0] and accuracy P (95.0; 95% CI [88.0-100.0]).

Conclusions: The studied formulas were found equivalent in terms of precision and accuracy, but the Ng-Schwartz-Munoz formula improved the accuracy at higher levels of in-GFR.
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http://dx.doi.org/10.1515/cclm-2020-0770DOI Listing
February 2021

Dynamic prediction models for graft failure in paediatric kidney transplantation.

Nephrol Dial Transplant 2021 Apr;36(5):927-935

INSERM, Bordeaux Population Health Research Center, University of Bordeaux, UMR1219, Bordeaux, France.

Background: Several models have been proposed to predict kidney graft failure in adult recipients but none in younger recipients. Our objective was to propose a dynamic prediction model for graft failure in young kidney transplant recipients.

Methods: We included 793 kidney transplant recipients waitlisted before the age of 18 years who received a first kidney transplantation before the age of 21 years in France in 2002-13 and survived >90 days with a functioning graft. We used a Cox model including baseline predictors only (sex, age at transplant, primary kidney disease, dialysis duration, donor type and age, human leucocyte antigen matching, cytomegalovirus serostatus, cold ischaemia time and delayed graft function) and two joint models also accounting for post-transplant estimated glomerular filtration rate (eGFR) trajectory. Predictive performances were evaluated using a cross-validated area under the curve (AUC) and R2 curves.

Results: When predicting the risk of graft failure from any time within the first 7 years after paediatric kidney transplantation, the predictions for the following 3 or 5 years were accurate and much better with the joint models than with the Cox model (AUC ranged from 0.83 to 0.91 for the joint models versus 0.56 to 0.64 for the Cox model).

Conclusion: Accounting for post-transplant eGFR trajectory strongly increased the accuracy of graft failure prediction in young kidney transplant recipients.
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http://dx.doi.org/10.1093/ndt/gfaa180DOI Listing
April 2021

Adherence to cysteamine in nephropathic cystinosis: A unique electronic monitoring experience for a better understanding. A prospective cohort study: CrYSTobs.

Pediatr Nephrol 2021 Mar 9;36(3):581-589. Epub 2020 Sep 9.

Hospices Civils de Lyon, Service de Néphrologie Pédiatrique, et centre de référence maladies rénales et phosphocalciques rares- Néphrogones- Filière ORKiD -69500, Bron, France.

Introduction: In nephropathic cystinosis (NC), adherence to cysteamine remains challenging; poor adherence is worsening the disease progression with a decline of kidney function and increase of extrarenal morbidities. Our objective was to describe adherence to cysteamine in NC patients, using electronic monitoring systems.

Methods: Patients with confirmed NC, aged > 4 years and receiving oral cysteamine (short acting or delayed release formulation as standard of care) from 3 French reference centers, were included. Adherence to treatment was primarily assessed as the percentage of days with a good adherence score, adherence score rating from 0 (poor) to 2 (good). A descriptive analysis was performed after 1-year follow-up.

Results: Seventeen patients (10 girls, median age: 13.9 (5.4-33.0) years) were included. Median age at diagnosis was 17.0 (3.0-76.9) months and age at start of cysteamine was 21.0 (15.5-116.3) months. Median daily dose of cysteamine was 1.05 (0.55-1.63) g/m/day. Over the year, the median percentage of days with a good adherence score was 80 (1-99)% decreasing to 68 (1-99)% in patients > 11 years old. The median of average number of hours covered by treatment in a day was 22.5 (6.1-23.9) versus 14.9 (9.2-20.5) hours for delayed release versus short acting cysteamine.

Conclusion: Our data are the first describing a rather good adherence to cysteamine, decreasing in adolescents and adults. We described a potential interest of the delayed release formulation. Our data highlight the need for a multidisciplinary approach including therapeutic education and individualized approaches in NC patients transitioning to adulthood. Graphical abstract.
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http://dx.doi.org/10.1007/s00467-020-04722-0DOI Listing
March 2021

Eplet incompatibility in pediatric renal transplantation.

Pediatr Transplant 2020 09 10;24(6):e13721. Epub 2020 May 10.

Department of Pediatric Nephrology, Hopital Femme-Mere-Enfant, Lyon, France.

Eplet incompatibility appears to be a better predictor of the de novo appearance of DSA post-Tx than HLA antigen matching in adults. We evaluated the HLA Matchmaker® software (version 2.1) in our pediatric cohort to predict the appearance of DSA post-Tx. We included 70 pediatric patients (26 girls, 10 living donors, mean age 11.2 ± 3.9 years) after a first R-Tx (January 2010-August 2016), without prior immunization, having complete HLA typing (A, B, C, DRB1 and DQB1) and DSA follow-up for at least one year. The mean of HLA and eplet incompatibilities was 4.7 ± 1.3 and 15.5 ± 6.1, respectively, with a correlation coefficient r between these two variables of 0.34 (P < .001). The eplet load was 12.8 ± 5.0 in living donors vs 15.9 ± 6.2 in deceased donors (P = NS), 12.6 ± 6.1 in preemptive R-Tx (n = 14) vs 16.3 ± 5.9 for non-preemptive R-Tx (P = .04). Seven patients (10%) developed DSA during the 3.5 ± 1.2 years post-Tx. The eplet load was 13.7 ± 5.5 for those who developed DSA vs 15.7 ± 6.1 for the others (P = NS). In our single-center series of pediatric R-Tx with good HLA matching and lower eplet load than previously published series, eplet incompatibilities do not predict the development of DSA. The question of the HLA matching requirement and the daily interest of the HLA Matchmaker® software to help select the grafts remain open.
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http://dx.doi.org/10.1111/petr.13721DOI Listing
September 2020

Collaboration between academics, small pharmaceutical company and patient organizations in the development of a new formulation of cysteamine in nephropathic cystinosis: A successful story.

Therapie 2020 Apr 13;75(2):169-173. Epub 2020 Feb 13.

Hospices civils de Lyon, EPICIME-CIC 1407 de Lyon, Inserm, department of clinical epidemiology, CHU-Lyon, 69677 Bron, France; Université de Lyon 1, 69000 Lyon, France.

Rare diseases usually concern small and disseminated population. Implementing clinical research with the right design, outcomes measures and the recruitment of patients are challenges. Collaborations, training and multidisciplinary approach are often required. In this article, we provide an overview of a successful collaboration in nephropathic cystinosis (NC), focusing on what was the key of success, the interactions between academics, the pharmaceutical company and patients organizations. NC is considered as a very rare disease. In 2010, a new formulation of cysteamine, the only available treatment to improve renal outcome of the disease, was proposed by a small American company. Studies were implemented in France under the coordination of an expert of the disease and the clinical investigation center of Lyon. The collaboration resulted in a good recruitment and retention of the patients in the study and most of all in the availability of the new formulation in France. Patients could have facilitated the research by being involved in the early stages of the studies. Involving patients and public early in the process is particularly important in rare diseases as the patient is a great source of knowledge and has his own expectations. Priorities of research, design, conduct and reporting of clinical trials can be defined in collaboration with adults but also with young patients or public, the first concerned in rare diseases. This concept is still to be developed and improved especially with paediatric patients.
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http://dx.doi.org/10.1016/j.therap.2020.02.008DOI Listing
April 2020

Neuropsychological and neuroanatomical phenotype in 17 patients with cystinosis.

Orphanet J Rare Dis 2020 02 26;15(1):59. Epub 2020 Feb 26.

Centre de référence des maladies rénales rares - Néphrogones - Filière ORKiD, Bron, France.

Background: Cystinosis is a rare autosomal recessive disorder caused by intracellular cystine accumulation. Proximal tubulopathy (Fanconi syndrome) is one of the first signs, leading to end-stage renal disease between the age of 12 and 16. Other symptoms occur later and encompass endocrinopathies, distal myopathy and deterioration of the central nervous system. Treatment with cysteamine if started early can delay the progression of the disease. Little is known about the neurological impairment which occurs later. The goal of the present study was to find a possible neuroanatomical dysmorphic pattern that could help to explain the cognitive profile of cystinosis patients. We also performed a detailed review of the literature on neurocognitive complications associated with cystinosis.

Methods: 17 patients (mean age = 17.6 years, [5.4-33.3]) with cystinosis were included in the study. Neuropsychological assessment was performed including intelligence (Intelligence Quotient (IQ) with Wechsler's scale), memory (Children Memory Scale and Wechsler Memory Scale), visuo-spatial (Rey's figure test) and visuo-perceptual skills assessments. Structural brain MRI (3 T) was also performed in 16 out of 17 patients, with high resolution 3D T1-weighted, 3D FLAIR and spectroscopy sequences.

Results: Intellectual efficiency was normal in patients with cystinosis (mean Total IQ = 93). However the Perceptual Reasoning Index (mean = 87, [63-109]) was significantly lower than the Verbal Comprehension Index (mean = 100, [59-138], p = 0.003). Memory assessment showed no difference between visual and verbal memory. But the working memory was significantly impaired in comparison with the general memory skills (p = 0.003). Visuospatial skills assessment revealed copy and reproduction scores below the 50th percentile rank in more than 70% of the patients. Brain MRI showed cortical and sub-cortical cerebral atrophy, especially in the parieto-occipital region and FLAIR hypersignals in parietal, occipital and brain stem/cerebellum. Patients with atrophic brain had lower Total IQ scores compared to non-atrophic cystinosis patients.

Conclusions: Patients with cystinosis have a specific neuropsychological and neuroanatomical profile. We suggest performing a systematic neuropsychological assessment in such children aiming at considering adequate management.
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http://dx.doi.org/10.1186/s13023-019-1271-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7045592PMC
February 2020

Patients with primary hyperoxaluria type 2 have significant morbidity and require careful follow-up.

Kidney Int 2019 12 3;96(6):1389-1399. Epub 2019 Sep 3.

Department of Nephrology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK.

Primary hyperoxaluria type 2 is a rare inherited disorder of glyoxylate metabolism causing nephrocalcinosis, renal stone formation and ultimately kidney failure. Previously, primary hyperoxaluria type 2 was considered to have a more favorable prognosis than primary hyperoxaluria type 1, but earlier reports are limited by low patient numbers and short follow up periods. Here we report on the clinical, genetic, and biochemical findings from the largest cohort of patients with primary hyperoxaluria type 2, obtained by a retrospective record review of genetically confirmed cases in the OxalEurope registry, a dataset containing 101 patients from eleven countries. Median follow up was 12.4 years. Median ages at first symptom and diagnosis for index cases were 3.2 years and 8.0 years, respectively. Urolithiasis was the most common presenting feature (82.8% of patients). Genetic analysis revealed 18 novel mutations in the GRHPR gene. Of 238 spot-urine analyses, 23 (9.7%) were within the normal range for oxalate as compared to less than 4% of 24-hour urine collections. Median intra-individual variation of 24-hour oxalate excretion was substantial (34.1%). At time of review, 12 patients were lost to follow-up; 45 of the remaining 89 patients experienced chronic kidney disease stage 2 or greater and 22 patients had reached stage 5. Median renal survival was 43.3 years, including 15 kidney transplantations in 11 patients (1 combined with liver transplantation). Renal outcome did not correlate with genotype, biochemical parameters or initially present nephrocalcinosis. Thus, primary hyperoxaluria type 2 is a disease with significant morbidity. Accurate diagnosis by 24-hour urine analysis and genetic testing are required with careful follow-up.
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http://dx.doi.org/10.1016/j.kint.2019.08.018DOI Listing
December 2019

School level of children carrying a HNF1B variant or a deletion.

Eur J Hum Genet 2020 01 3;28(1):56-63. Epub 2019 Sep 3.

Service de Pédiatrie, CHU de Limoges, Limoges, France.

The prevalence of neurological involvement in patients with a deletion of or a variant in the HNF1B gene remains discussed. The aim of this study was to investigate the neuropsychological outcomes in a large cohort of children carrying either a HNF1B whole-gene deletion or a disease-associated variant, revealed by the presence of kidney anomalies. The neuropsychological development-based on school level-of 223 children included in this prospective cohort was studied. Data from 180 children were available for analysis. Patients mean age was 9.6 years, with 39.9% of girls. Among these patients, 119 carried a HNF1B deletion and 61 a disease-associated variant. In the school-aged population, 12.7 and 3.6% of patients carrying a HNF1B deletion and a disease-associated variant had special educational needs, respectively. Therefore, the presence of a HNF1B deletion increases the risk to present with a neuropsychiatric involvement when compared with the general population. On the other hand, almost 90% of patients carrying a HNF1B disease-associated variant or deletion have a normal schooling in a general educational environment. Even if these findings do not predict the risk of neuropsychiatric disease at adulthood, most patients diagnosed secondary to kidney anomalies do not show a neurological outcome severe enough to impede standard schooling at elementary school. These results should be taken into account in prenatal counseling.
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http://dx.doi.org/10.1038/s41431-019-0490-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6906503PMC
January 2020

Minoxidil versus placebo in the treatment of arterial wall hypertrophy in children with Williams Beuren Syndrome: a randomized controlled trial.

BMC Pediatr 2019 05 28;19(1):170. Epub 2019 May 28.

Hospices Civils de Lyon, Service de Néphrologie Pédiatrique, et centre de référence maladies rénales rares- Néphrogones, Filière ORKiD, -69500, Bron, France.

Background: Insufficient elastin synthesis leads to vascular complications and arterial hypertension in children with Williams-Beuren syndrome. Restoring sufficient quantity of elastin should then result in prevention or inhibition of vascular malformations and improvement in arterial blood pressure.

Methods: The aim of this study was to assess the efficacy and safety of minoxidil on Intima Media Thickness (IMT) on the right common carotid artery after twelve-month treatment in patient with Williams-Beuren syndrome. We performed a randomized placebo controlled double blind trial. All participants were treated for 12 months and followed for 18 months. The principal outcome was assessed by an independent adjudication committee blinded to the allocated treatment groups.

Results: The principal outcome was available for 9 patients in the placebo group and 8 patients in the minoxidil group. After 12-month treatment, the IMT in the minoxidil group increased by 0.03 mm (95% CI -0.002, 0.06) compared with 0.01 mm (95%CI - 0.02, 0.04 mm) in the placebo group (p = 0.4). Two serious adverse events unrelated to the treatment occurred, one in the minoxidil and 1 in the placebo group. After 18 months, the IMT increased by 0.07 mm (95% CI 0.04, 0.10 mm) in the minoxidil compared with 0.01 mm (95% CI -0.02, 0.04 mm) in the placebo group (p = 0.008).

Conclusion: Our results suggest a slight increase after 12 and 18-month follow-up in IMT. More understanding of the biological changes induced by minoxidil should better explain its potential role on elastogenesis in Williams-Beuren syndrome.

Trials Registration: US National Institutes of Health Clinical Trial Register (NCT00876200). Registered 3 April 2009 (retrospectively registered).
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http://dx.doi.org/10.1186/s12887-019-1544-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6537216PMC
May 2019

Adverse events associated with currently used medical treatments for cystinuria and treatment goals: results from a series of 442 patients in France.

BJU Int 2019 11 25;124(5):849-861. Epub 2019 Mar 25.

Department of Urology, Strasbourg University Hospital, Strasbourg University, Strasbourg, France.

Objective: To evaluate medical treatments, in terms of adverse events (AEs) and therapeutic goals, in a large series of patients with cystinuria.

Patients And Methods: Data from 442 patients with cystinuria were recorded retrospectively. Crystalluria was studied in 89 patients. A mixed-effects logistic regression model was used to estimate how urine pH, specific gravity and cysteine-binding thiols (CBT) correlate with risk of cystine crystalluria.

Results: Alkalizing agents and CBT agents were given to 88.8% (n = 381) and 55.3% (n = 238) of patients, respectively. Gastrointestinal AEs were reported in 12.3%, 10.4% and 2.6% of patients treated with potassium bicarbonate, potassium citrate and sodium bicarbonate, respectively (P = 0.008). The percentages of patients who experienced at least one AE with tiopronin (24.6%) and with D-penicillamine (29.5%) were similar (P = 0.45). Increasing urine pH and decreasing urine specific gravity significantly reduced the risk of cystine crystalluria, whereas D-penicillamine and tiopronin treatments did not reduce this risk (odds ratio [OR] 1 for pH ≤6.5; OR 0.52 [95% confidence interval {95% CI} 0.28-0.95] for 7.0 8.0, P <0.001).

Conclusion: Adverse events were frequent with D-penicillamine and tiopronin. Alkaline hyperdiuresis was well tolerated and reduced cystine crystalluria. Urine specific gravity ≤1.005 and urine pH >7.5, while warning about calcium-phosphate crystallization, should be the goals of medical therapy.
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http://dx.doi.org/10.1111/bju.14721DOI Listing
November 2019

Towards adulthood with a solitary kidney.

Pediatr Nephrol 2019 11 1;34(11):2311-2323. Epub 2018 Oct 1.

Centre de référence des maladies rénales rares Néphrogones, Hospices Civils de Lyon, Lyon, France.

Around 1/1000 people have a solitary kidney. Congenital conditions mainly include multicystic dysplastic kidney and unilateral renal aplasia/agenesis; acquired conditions are secondary to nephrectomy performed because of urologic structural abnormalities, severe parenchymal infection, renal trauma, and renal or pararenal tumors. Children born with congenital solitary kidney have a better long-term glomerular filtration rate than those with solitary kidney secondary to nephrectomy later in life. Acute and chronic adaptation processes lead to hyperfiltration followed by fibrosis in the remnant kidney, with further risk of albuminuria, arterial hypertension, and impaired renal function. Protective measures rely on non-pharmacological renoprotection (controlled protein and sodium intake, avoidance/limitation of nephrotoxic agents, keeping normal body mass index, and limitation of tobacco exposure). Lifelong monitoring should include blood pressure and albuminuria assessment, completed by glomerular filtration rate (GFR) estimation in case of abnormal values. In the absence of additional risk factors to solitary kidney, such assessment can be proposed every 5 years. There is no current consensus for indication and timing of pharmacological intervention.
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http://dx.doi.org/10.1007/s00467-018-4085-1DOI Listing
November 2019

Skin microvascular dysfunction as an early cardiovascular marker in primary hyperoxaluria type I.

Pediatr Nephrol 2019 02 1;34(2):319-327. Epub 2018 Oct 1.

Centre de Référence des Maladies Rénales Rares, Service de Néphrologie et Rhumatologie Pédiatriques, Hospices Civils de Lyon, Lyon, France.

Background: Primary hyperoxaluria type 1 (PH1) is an orphan inborn error of oxalate metabolism leading to hyperoxaluria, progressive renal failure, oxalate deposition, and increased cardiovascular complications. As endothelial dysfunction and arterial stiffness are early markers of cardiovascular risk, we investigated early endothelial and vascular dysfunction in young PH1 patients either under conservative treatment (PH1-Cons) or after combined kidney liver transplantation (PH1-T) in comparison to healthy controls (Cont-H) and patients with a past of renal transplantation (Cont-T).

Methods: Skin microvascular function was non-invasively assessed by laser Doppler flowmetry before and after stimulation by current, thermal, or pharmacological (nitroprussiate (SNP) or acetylcholine (Ach)) stimuli in young PH1 patients and controls.

Results: Seven PH1-Cons (6 F, median age 18.2) and 6 PH1-T (2 F, median age 13.3) were compared to 96 Cont-H (51 F, median age 14.2) and 6 Cont-T (4 F, median age 14.5). The endothelium-independent vasodilatation (SNP) was severely decreased in PH1-T compared to Cont-H. Ach, current-induced vasodilatation (CIV), and thermal response was increased in PH1-Cons and Cont-T compared to controls.

Conclusions: PH1-T patients displayed severely decreased smooth muscle capacity to vasodilate. An exacerbated endothelial-dependent vasodilation suggests a role for silent inflammation in the early dysfunction of microcirculation observed in PH1-Cons and Cont-T.
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http://dx.doi.org/10.1007/s00467-018-4081-5DOI Listing
February 2019

Renal Replacement Therapy in children with severe developmental disability: guiding questions for decision-making.

Eur J Pediatr 2018 Dec 7;177(12):1735-1743. Epub 2018 Sep 7.

Department of Pediatric Nephrology and Organ Transplantation, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium.

Whether to initiate or to withhold Renal Replacement Therapy (RRT) in children with severe developmental disability (DD) remains a topic of intense debate. The present study investigated the opinion of professionals on this difficult issue and proposed a checklist with guiding questions for decision-making. Clinicians affiliated to different organizations involved in pediatric nephrology worldwide were invited to respond to a web-based survey. This survey focused on the collection of demographic data of the respondents together with their opinion concerning the decision-making regarding RRT in a particular case and for children with severe DD in general. A total of 286 professionals responded to the survey. Sixty-six percent supported initiating RRT in the child of the case report, with pre-emptive transplantation being the preferred modality. Important arguments pro RRT initiation in children with severe DD in general were parental preference, decrease of suffering, and improvement of survival and quality of life. Important contraindications included low IQ, severe comorbidities, and inability of the patient to take medication or for the family to provide sufficient care.Conclusion: The present study presents an inventory on the opinions of health care professionals involved in RRT in children regarding the treatment of children with DD and assists in the decision-making process by identifying important medical and psychosocial arguments for initiating or withholding RRT in severe DD patients. What is Known: •Renal Replacement Therapy (RRT) in children with severe developmental disability (DD) is a topic of intense debate. •Previous studies on the opinion of professionals mainly focused on the use of IQ as an argument in the decision-making whether or not starting RRT. What is New: •The present study investigated the opinion of professionals with regard to considering initiation or withholding RRT in children with severe DD and identified medical and psychosocial arguments playing a role in the decision-making process. •Based on these arguments, a checklist with guiding questions for decision-making is proposed.
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http://dx.doi.org/10.1007/s00431-018-3238-3DOI Listing
December 2018

Cytomegalovirus infection in the first year after pediatric kidney transplantation.

Nephrol Ther 2019 Mar 8;15(1):44-50. Epub 2018 Jun 8.

Centre de référence des maladies rénales rares, service de néphrologie, rhumatologie dermatologie pédiatriques, hospices civils de Lyon, 69003 Lyon, France; Université Claude-Bernard Lyon 1, 69000 Lyon, France.

Cytomegalovirus is common in adult recipients (prevalence of 40-90%). Children are typically seronegative but immunosuppression may prone to primary-infection or viral reactivation, with potentially severe consequences. CMV infection incidence in pediatric kidney transplant recipients has seldom been investigated. The aim of our study was to evaluate the incidence and timing of CMV infection during the first year after renal transplantation. We assembled a retrospective cohort of 136 children who had received a kidney transplant between 2003 and 2014 with a year follow-up. The patients were classified regarding CMV infection as high risk (D+/R-), intermediate risk (R+) or low risk (D-/R-). CMV infection was defined by the viral replication remaining asymptomatic whereas CMV disease concerned viral replication with clinical and/or biological symptoms. Oral valganciclovir was used as prophylaxis for high-risk recipients. A total of 38 patients (27.9%) developed CMV infection, 13 (40.6%) of the 32 D+/R-, 24 (45.3%) of the 53 R+ and 1 (2.0%) of the 51 D-/R-. Of these 38 infected patients, 10 developed tissue-invasive disease. During the first year after kidney transplantation, 27.9% of recipients developed CMV infection. This study confirms the influence of donor and recipient CMV status on infection propensity and highlights the importance of adequate follow-up for intermediate risk patients.
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http://dx.doi.org/10.1016/j.nephro.2018.04.003DOI Listing
March 2019

Association between glomerular filtration rate (measured by high-performance liquid chromatography with iohexol) and plasma oxalate.

J Bras Nefrol 2018 Jan-Mar;40(1):73-76. Epub 2018 Apr 9.

Université Claude-Bernard, Groupement Hospitalier Edouard Herriot, Hospices Civils de Lyon, UMR 5305, Rhone-Alpes, Lyon, France.

Introduction: Secondary hyperoxalemia is a multifactorial disease that affects several organs and tissues in patients with native or transplanted kidneys. Plasma oxalate may increase during renal failure because it is cleared from the body by the kidneys. However, there is scarce evidence about the association between glomerular filtration rate and plasma oxalate, especially in the early stages of chronic kidney disease (CKD).

Methods: A case series focuses on the description of variations in clinical presentation. A pilot study was conducted using a cross-sectional analysis with 72 subjects. The glomerular filtration rate (GFR) and plasma oxalate levels were measured for all patients. Results: Median (IQR) GFR was 70.50 [39.0; 91.0] mL/min/1.73 m2. Plasma oxalate was < 5.0 µmol/L in all patients with a GFR > 30 mL/min/1.73m2. Among the 14 patients with severe CKD (GFR < 30 mL/min/1.73 m2) only 4 patients showed a slightly increased plasma oxalate level (between 6 and 12 µmol/L).

Conclusion: In non-primary hyperoxaluria, plasma oxalate concentration increases when GFR < 30mL/min/1.73 m2 and, in our opinion, values greater than 5 µmol/L with a GFR > 30 mL/min/1.73 m2 are suggestive of primary hyperoxaluria. Further studies are necessary to confirm plasma oxalate increase in patients with low GFR levels (< 30mL/min/1.73 m2).
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http://dx.doi.org/10.1590/1678-4685-JBN-3743DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6533971PMC
January 2019

[PKHD1 mutations in autosomal recessive polycystic kidney disease (ARPKD): Genotype-phenotype correlations from a series of 308 cases to improve prenatal counselling].

Nephrol Ther 2018 Nov 25;14(6):474-477. Epub 2018 Apr 25.

UM pathologies endocriniennes, rénales, musculaires et mucoviscidose, CBPE, groupement hospitalier Est, 59, boulevard Pinel, 69677 Bron cedex, France.

Objectives: ARPKD is a recessive rare disease due to PKHD1 mutation. The main objective of the study was to characterize the phenotypic variability according to the different types of PKHD1 mutations.

Methods: This study was performed in 308 ARPKD patients with a genetic diagnosis from our genetic center. Related physicians provided minimal clinical and biological data.

Results: Patients were divided into three genotypic groups: the first group (G1; n=65) consisted of patients with two truncating mutations, the second group (G2; n=117) of patients with one truncating and one non-truncating mutation, and the third group (G3; n=126) of patients with two non-truncating mutations. In the entire cohort, the outcomes consisted of 31% of pregnancy termination, 18% of neonatal deaths and 51% of patient survival after the neonatal period. The proportion of severe ARPKD (pregnancy termination or neonatal death) was significantly greater in G1: 94% versus 47% in G2 and 27% in G3 (P<0.001).

Conclusion: The presence of two truncating mutations in PKHD1 is associated with the most severe perinatal phenotype. However, the phenotypic variability observed in the other genotypic groups requires caution for prenatal counseling.
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http://dx.doi.org/10.1016/j.nephro.2018.03.002DOI Listing
November 2018

Teenagers and young adults with nephropathic cystinosis display significant bone disease and cortical impairment.

Pediatr Nephrol 2018 07 12;33(7):1165-1172. Epub 2018 Feb 12.

Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, 59 boulevard Pinel, 69677, Bron Cedex, France.

Background: Bone impairment appears to be a novel complication of nephropathic cystinosis despite cysteamine therapy. Its exact underlying pathophysiology is nevertheless unclear. The objective of this study was to evaluate bone status among patients included in the French Crystobs study.

Methods: In addition to clinical data, bone status was evaluated using biomarkers (ALP, PTH, 25-D, 1-25D, FGF23), DXA (spine and total body), and high-resolution peripheral quantitative computed tomography (HR-pQCT) at the tibia and radius. Results were compared to age- and gender-matched healthy controls (1:2 basis) from the local reference cohorts.

Results: At a median age of 22.5 (10.2-34.6) years, 10 patients with nephropathic cystinosis were included (2 receiving conservative therapies, 2 undergoing hemodialysis, 6 with a past of renal transplantation); 7 out of 10 patients complained of a bone symptom (past of fracture, bone deformations, and/or bone pain). Biochemicals and spine DXA did not show any significant abnormalities. Using HR-pQCT, significant decreases in cortical parameters (e.g., cortical thickness 850 (520-1100) versus 1225 (480-1680) μm; p < 0.05) and total volumetric bone mineral density (290 (233-360) versus 323 (232-406) mg/cm; p < 0.05) were observed in cystinotic patients in comparison to controls at the tibia. There were no differences for trabecular parameters. Similar results were observed at the radius.

Conclusions: In this pilot study, bone impairment (rather cortical than trabecular) is a significant clinical problem in nephropathic cystinosis; 70% of patients displayed significant bone symptoms, during teenage or young adulthood. This new complication should be known by physicians because of its potential dramatic impact on quality of life.
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http://dx.doi.org/10.1007/s00467-018-3902-xDOI Listing
July 2018

Bone disease in nephropathic cystinosis is related to cystinosin-induced osteoclastic dysfunction.

Nephrol Dial Transplant 2018 09;33(9):1525-1532

Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France.

Background: Bone impairment is a poorly described complication of nephropathic cystinosis (NC). The objectives of this study were to evaluate in vitro effects of cystinosin (CTNS) mutations on bone resorption and of cysteamine treatment on bone cells [namely human osteoclasts (OCs) and murine osteoblasts].

Methods: Human OCs were differentiated from peripheral blood mononuclear cells (PBMCs) of patients and healthy donors (HDs). Cells were treated with increasing doses of cysteamine in PBMCs or on mature OCs to evaluate its impact on differentiation and resorption, respectively. Similarly, cysteamine-treated osteoblasts derived from murine mesenchymal stem cells were assessed for differentiation and activity with toxicity and proliferation assays.

Results: CTNS was expressed in human OCs derived from HDs; its expression was regulated during monocyte colony-stimulating factor- and receptor activator of nuclear factor-κB-dependent osteoclastogenesis and required for efficient bone resorption. Cysteamine had no impact on osteoclastogenesis but inhibited in vitro HD osteoclastic resorption; however, NC OC-mediated bone resorption was impaired only at high doses. Only low concentrations of cysteamine (50 μM) stimulated osteoblastic differentiation and maturation, while this effect was no longer observed at higher concentrations (200 µM).

Conclusion: CTNS is required for proper osteoclastic activity. In vitro low doses of cysteamine have beneficial antiresorptive effects on healthy human-derived OCs and may partly correct the CTNS-induced osteoclastic dysfunction in patients with NC. Moreover, in vitro low doses of cysteamine also stimulate osteoblastic differentiation and mineralization, with an inhibitory effect at higher doses, likely explaining, at least partly, the bone toxicity observed in patients receiving high doses of cysteamine.
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http://dx.doi.org/10.1093/ndt/gfx362DOI Listing
September 2018

Renal transplantation in children under 3 years of age: Experience from a single-center study.

Pediatr Transplant 2018 03 17;22(2). Epub 2018 Jan 17.

Service de néphrologie rhumatologie dermatologie pédiatriques, Hôpital Femme Mère Enfant, Bron, France.

RTx remains challenging in children under 3 years of age. This single-center study reviewed the medical records of children <3 years transplanted since 1987 (N = 32, Group 1). They were matched for donor type and RTx period with children aged 3-13 years (N = 32, Group 2) and 13-18 years (N = 32, Group 3). There were no between-group significant differences regarding distributions of gender, primary renal disease, proportion of dialysis before RTx, and growth (SDS). Compared to Groups 2 and 3, Group 1 had more peritoneal dialyses (P < .001), more EBV mismatches (P = .04), and longer warm ischemia times (P < .001). The risk of graft loss was not significantly different among age groups (hazard ratio, 2.4 in Group 2 and 2.0 in Group 3 vs Group 1; P = .2). Death occurred in four patients (3 in Group 1 and 1 in Group 2) and graft loss occurred in 28 patients, mainly due to chronic allograft nephropathy. In recipients <3 years of age, the outcomes of RTx are close to those obtained in older pediatric age groups. Thus, young patients may be transplanted in experienced multidisciplinary teams without additional risks provided that particular attention is paid to donor selection and prevention/early diagnosis of comorbidities and complications.
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http://dx.doi.org/10.1111/petr.13116DOI Listing
March 2018

Standardization of pediatric uroradiological terms: A multidisciplinary European glossary.

J Pediatr Urol 2017 Dec 13;13(6):641-650. Epub 2017 Jul 13.

Pediatric Nephrology, Centro Hospitalar São João, Porto, Portugal.

To promote the standardization of nephro-uroradiological terms used in children, the European Society of Pediatric Radiology uroradiology taskforce wrote a detailed glossary. This work has been subsequently submitted to European experts in pediatric urology and nephrology for discussion and acceptance to improve the quality of radiological reports and communication among different clinicians involved in pediatric urology and nephrology.
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http://dx.doi.org/10.1016/j.jpurol.2017.05.026DOI Listing
December 2017

Standardization of pediatric uroradiological terms: a multidisciplinary European glossary.

Pediatr Radiol 2018 02 15;48(2):291-303. Epub 2017 Nov 15.

Pediatric Nephrology, Centro Hospitalar São João, Porto, Portugal.

To promote the standardization of nephro-uroradiological terms used in children, the European Society of Paediatric Radiology uroradiology taskforce wrote a detailed glossary. This work has been subsequently submitted to European experts in pediatric urology and nephrology for discussion and acceptance to improve the quality of radiological reports and communication between different clinicians involved in pediatric urology and nephrology.
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http://dx.doi.org/10.1007/s00247-017-4006-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5790858PMC
February 2018

Evidence for Bone and Mineral Metabolism Alterations in Children With Autosomal Dominant Polycystic Kidney Disease.

J Clin Endocrinol Metab 2017 11;102(11):4210-4217

Department of Pediatric Nephrology, University Hospitals Leuven, Leuven 3000, Belgium.

Context: Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary kidney disease. Hypophosphatemia was demonstrated in adult patients with preserved renal function, together with high fibroblast growth factor 23 (FGF23) and low soluble Klotho levels. The latter explained the relative FGF23 hyporesponsiveness in this cohort.

Objective: Evaluating phosphate and bone mineral metabolism in children with ADPKD compared with what is known in adult ADPKD patients.

Design: Observational cross-sectional study.

Setting: Multicenter study via ambulatory care in tertiary centers.

Participants: Ninety-two children with ADPKD (52 males; mean ± standard deviation age, 10.2 ± 5.0 years) and 22 healthy controls (HCs, 10 males; mean ± standard deviation age, 10.3 ± 4.1 years).

Main Outcome Measures: The predictor was early ADPKD stage. Bone mineral metabolism and renal phosphate handling were the main outcome measures. Performed measurements were serum phosphate, tubular maximum phosphorus reabsorption per glomerular filtration rate, FGF23, soluble Klotho, sclerostin, and bone alkaline phosphatase.

Results: ADPKD children had significantly lower serum phosphate levels compared with HC. Low tubular maximum phosphorus reabsorption per glomerular filtration rate was observed in 24% of patients, although not significantly different from HC. Serum FGF23 and soluble Klotho levels were comparable between patients and HC. In addition, we showed decreased bone alkaline phosphatase levels in ADPKD children, suggesting suppressed bone formation.

Conclusions: This report demonstrates hypophosphatemia and suppressed bone formation in a pediatric ADPKD cohort, with preserved renal function, compared with HC. Although FGF23 levels were not different from controls, they should be considered inappropriate, given the concomitant hypophosphatemia. Further studies are required to elucidate underlying pathophysiology and potential clinical consequences.
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http://dx.doi.org/10.1210/jc.2017-01157DOI Listing
November 2017