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Patient registries for rare diseases enable systematic data collection and can also be used to facilitate postauthorization safety studies (PASS) for orphan drugs. This study evaluates the PASS for betaine anhydrous (Cystadane), conducted as public private partnership (PPP) between the European network and registry for homocystinurias and methylation defects and the marketing authorization holder (MAH). Data were prospectively collected, 2013–2016, in a noninterventional, international, multicenter, registry study. Putative adverse and severe adverse events were reported to the MAH's pharmacovigilance. In total, 130 individuals with vitamin B6 nonresponsive (N = 54) and partially responsive (N = 7) cystathionine beta-synthase (CBS) deficiency, as well as 5,10-methylenetetrahydrofolate reductase (MTHFR; N = 21) deficiency and cobalamin C (N = 48) disease were included. Median (range) duration of treatment with betaine anhydrous was 6.8 (0–9.8) years. The prescribed betaine dose exceeded the recommended maximum (6 g/day) in 49% of individuals older than 10 years because of continued dose adaptation to weight; however, with disease-specific differences (minimum: 31% in B6 nonresponsive CBS deficiency, maximum: 67% in MTHFR deficiency). Despite dose escalation no new or potential risk was identified. Combined disease-specific treatment decreased mean ± SD total plasma homocysteine concentrations from 203 ± 116 to 81 ± 51 μmol/L (p < 0.0001), except in MTHFR deficiency. Recommendations for betaine anhydrous dosage were revised for individuals ≥ 10 years. PPPs between MAH and international scientific consortia can be considered a reliable model for implementing a PASS, reutilizing well-established structures and avoiding data duplication and fragmentation.

Nephronophthisis (NPH) is an autosomal-recessive ciliopathy representing one of the most frequent causes of kidney failure in childhood characterized by a broad clinical and genetic heterogeneity. Applied to one of the worldwide largest cohorts of patients with NPH, genetic analysis encompassing targeted and whole exome sequencing identified disease-causing variants in 600 patients from 496 families with a detection rate of 71%. Of 788 pathogenic variants, 40 known ciliopathy genes were identified. However, the majority of patients (53%) bore biallelic pathogenic variants in NPHP1. NPH-causing gene alterations affected all ciliary modules defined by structural and/or functional subdomains. Seventy six percent of these patients had progressed to kidney failure, of which 18% had an infantile form (under five years) and harbored variants affecting the Inversin compartment or intraflagellar transport complex A. Forty eight percent of patients showed a juvenile (5-15 years) and 34% a late-onset disease (over 15 years), the latter mostly carrying variants belonging to the Transition Zone module. Furthermore, while more than 85% of patients with an infantile form presented with extra-kidney manifestations, it only concerned half of juvenile and late onset cases. Eye involvement represented a predominant feature, followed by cerebellar hypoplasia and other brain abnormalities, liver and skeletal defects. The phenotypic variability was in a large part associated with mutation types, genes and corresponding ciliary modules with hypomorphic variants in ciliary genes playing a role in early steps of ciliogenesis associated with juvenile-to-late onset NPH forms. Thus, our data confirm a considerable proportion of late-onset NPH suggesting an underdiagnosis in adult chronic kidney disease.

Background Several cases of idiopathic nephrotic syndrome (INS) relapse following the administration of coronavirus disease 2019 (COVID-19) vaccines have recently been reported, raising questions about the potential relationship between the immune response to COVID-19 vaccination and INS pathogenesis. Methods We performed a retrospective multicentre survey describing the clinical and biological characteristics of patients presenting a relapse of INS after COVID-19 vaccination, with an assessment of outcome under treatment. Results We identified 25 patients (16 men and 9 women) presenting a relapse within 1 month of a COVID-19 vaccine injection. The glomerular disease was of childhood onset in half of the patients and most patients (21/25) had received at least one immunosuppressive drug in addition to steroids for frequently relapsing or steroid-dependent nephrotic syndrome (NS). All patients were in a stable condition at the time of injection and 11 had no specific treatment. In five patients, the last relapse was reported >5 years before vaccine injection. The Pfizer-BioNTech (BNT162b2) vaccine was used in 80% of the patients. In 18 cases, INS relapse occurred after the first injection, a mean of 17.5 days after vaccination. A second injection was nevertheless administered in 14 of these patients. Five relapses occurred after administration of the second dose and two relapses after the administration of the third dose. All but one of the patients received steroids as first-line treatment, with an additional immunosuppressive agent in nine cases. During follow-up, complete remission was achieved in 21 patients, within 1 month in 17 cases. Only one patient had not achieved at least partial remission after 3 months of follow-up. Conclusions This case series suggests that, in rare patients, COVID-19 vaccination may trigger INS relapse that is generally easy to control. These findings should encourage physicians to persuade their patients to complete the COVID-19 vaccination schedule.

Clinical recommendations; Cystinosis; Multidisciplinary care Recomendaciones clínicas; Cistinosis; Atención multidisciplinaria Recomanacions clíniques; Cistinosi; Atenció multidisciplinària Cystinosis, a rare autosomal recessive lysosomal storage disorder, results in an abnormal accumulation of the amino acid cystine in multiple organs and tissues of the body. Renal symptoms typically develop in the first few months of life, with extra-renal manifestations becoming apparent over the next 10–20 years, which require coordinated multidisciplinary care. Here, we describe a consensus-based guidance to support the management of adolescents and adults living with cystinosis. The programme was led by a Steering Committee (SC) of six experts in the management of patients with cystinosis, who identified a list of 15 key questions reflecting the multi-organ effects of cystinosis. An Extended Faculty (EF) of eight additional specialists was invited to answer the questions via an online digital platform using a quasi-Delphi approach. The consolidated answers were summarized into recommendations. Where evidence was lacking, recommendations were developed using collective expert consensus. The EF was asked to agree/disagree with the clinical recommendations. The expert-agreed clinical recommendations provide guidance that considers both renal and extra-renal systems. The topics covered are advice on fertility and family planning, consideration of the nervous, muscular, ophthalmic, cardio-respiratory, endocrine, dermatological and gastrointestinal systems, as well as guidance on dental care, diet, lifestyle, and improving quality of life and psychological well-being. In summary, this work outlines recommendations and a checklist for clinicians with a vision for improving and standardizing the multidisciplinary care for patients with cystinosis. The programme was supported by Chiesi Farmaceutici Spa. Chiesi was not involved in the content or outcomes of the programme which were solely determined by the SC and extended faculty experts.

Resume Des recommandations specifiques a la nephrologie ont ete redigees sous l’egide de l’Association internationale de nephrologie pediatrique en 2011. Ces recommandations preconisent une transition individualisee, debutant entre 12 et 14 ans, avec des informations sur la maladie et les traitements du patient adaptees a l’âge et au niveau intellectuel. Les recommandations insistent sur l’importance d’identifier un referent pediatre et un referent en service adulte, ainsi qu’une equipe paramedicale et de travailleurs sociaux ; elles insistent egalement sur l’importance d’associer les aidants (les familles et l’entourage proche, etc.), la necessite d’un dossier specifique de transition et d’une visite prealable du service adulte avant le transfert. L’International Pediatric Nephrology Association recommande que le transfert soit realise au « bon moment » de la vie du jeune et non a ses 18 ans ; ce « bon moment » etant defini par le moment ou le jeune se sent pret, en periode de stabilite aussi bien medicale que familiale, scolaire et sociale. Afin de fournir au jeune des competences d’autogestion (empowerment) appropriees de sa maladie et de sa vie, dans le cadre de la filiere maladies renales rares (ORKiD), nous avons elabore un programme avec questionnaire adapte a l’âge en nous inspirant de celui mis en place a Southampton au Royaume-Uni. Ce document presente les outils developpes par le groupe de travail de la filiere de soins ORKiD.

Maple syrup urine disease (MSUD) is a rare inborn metabolic disorder, managed with a strict protein‐restricted diet. At any time or age patients may still experience metabolic decompensations, requiring administration of branched chain amino acid (BCAA)‐free formula to reduce leucine levels. This retrospective observational study of 126 decompensation episodes from 54 MSUD patients treated at five centers in France and Germany from 2010 to 2016, describes episodes and outcomes for patients stratified into groups who received enteral/oral or intravenous (IV) BCAA‐free formula, and by pediatric or adult age categories. IV administration of BCAA‐free formula was required in cases of gastric intolerance (33%), refusal to undergo nasogastric tubing (31%), “emergency” (14%) or coma patients (8%), and as prophylaxis before surgery (6%). Overall, mean duration of hospitalization was 6.6 days with oral/enteral BCAA‐free formula and 5.4 days with IV formula. Leucine levels at discharge decreased by a mean of 548.5 μmol/L (69.3%) in the oral/enteral group and 657.2 μmol/L (71.3%) in the IV group. In the pediatric subgroup, there were no marked differences between administration groups on any outcome. In the adult subgroup, mean time to episode resolution was 15.8 days in the oral/enteral group and 7.7 days in the IV group (P = .008); mean duration of hospitalization was 6 days in the oral/enteral group and 4.6 days in the IV group (P = NS). Overall, seven serious adverse events in two patients were reported, of which only nausea and vomiting were treatment related.

BACKGROUND AND AIMS Little is known about the long-term outcome during adulthood of childhood onset idiopathic nephrotic syndrome (INS). We aimed to determine which patients require long-term follow up after transition, to identify risk factors of relapse and to analyze treatment strategies. METHOD In this monocentric retrospective study, we included all patients admitted in our adult nephrology department with INS diagnosed during childhood. Patients who reached kidney failure during childhood were excluded. Data regarding the outcome at adult age were obtained through clinical database and medical charts. RESULTS Eighty-two patients (male/female = 2/1) were included, with a median age at diagnosis of 3.9 years (1.2–16.5). Sixty-eight patients had steroid-sensitive INS, including 52 with steroid-dependent nephrotic syndrome or frequently relapsing nephrotic syndrome. Fourteen patients had steroid-resistant nephrotic syndrome. A total of 89% of patients received corticosteroid sparing treatment during childhood. Median follow-up during adulthood was 6.2 (0.3–25) years. A total of 71% of patients experienced at least one relapse during adulthood. The total number of relapses during childhood and the number of relapses per year during childhood, reflecting disease activity, were significantly higher in patients who experienced relapses during adulthood than in patients who did not (Figure 1). The risk of relapse during adulthood was also significantly associated with the need for immunosuppressive regimen at the time of the transition visit (P = 0.002). To promote the successful transition of young people, we propose to organize a transition visit where the adolescent/young adult is seen jointly by pediatric and adult nephrologists, as it was done for 68% of patients in this study. The relapse rate was significantly lower (50%) in the subgroup of patients who had such a transition visit. We also found that relapse during the first two-years of adulthood follow-up was significantly associated with the risk of further relapse, highlighting the need for a close follow-up during the transition period. A total of 45% of patients received corticosteroid sparing treatment during adulthood, mainly mycophenolate mofetil (N = 23), calcineurin inhibitors (N = 21) and rituximab (N = 12). The main complications were high blood pressure (20/82, 26%) and osteopenia (19/26, 73% when bone densitometry was performed). Only one thrombo-embolic event and three severe infections were reported. At last follow-up, median eGFR was 87.1 (23.4–150.8) mL/min/1.73 m². CONCLUSION The incidence of relapses in adulthood is high in patients with active disease during childhood. A long-term follow-up is mandatory in these patients. Whereas renal function remained normal in most patients, high blood pressure and osteopenia were frequent and should be carefully monitored during adulthood. Transition visit should be carefully coordinated to prevent the risk of nonadherence.

Nicolas Postel-Vinay,1,2 Jiali-Delphine Shao,3 Anne Pinton,4 Aude Servais,5 Nicole Gebara,1 Laurence Amar1 1Hypertension Unit, ESH Excellence Center, Hôpital Européen Georges Pompidou, APHP, Paris, France; 2Hospital at Home, Fondation Santé Service, Levallois, France; 3Faculté de médecine de l’Université Paris Saclay, Le Kremlin Bicêtre, France; 4Department of Obstetrics and Gynecology, Trousseau Hospital, APHP, Sorbonne University, Paris, France; 5Nephrology and Transplantation Department, Necker Hospital, APHP, Paris, FranceCorrespondence: Nicolas Postel-Vinay, Email nicolas.postel-vinay@aphp.frIntroduction: Hy-Result is a rule management system designed to help patients to be compliant with the home blood pressure measurement (HBPM) monitoring schedule and to understand their BP readings. The aim of the Hy-Result e-Health prospective study is to evaluate the practice and experience of women using the Hy-Result coaching app for self-interpretation of BP readings during and after pregnancy.Methods: Participants were asked to: i) measure their BP at home; ii) use the Hy-Result app and send their PDF report to the researcher; iii) answer anonymously to 3 online independent questionnaires (Q).Results: A total of 107 women accepted to measure their BP and use the app. Among them 82 (77%) performed HBPM and used successfully the system and 72 (88%) shared to the investigator their PDF report by email. Of these, 95% declared the software was “easy” or “very easy” to use; 93% believe the software helps them to monitor their BP more effectively (74% agree, 18% somewhat agree); 94% that the color code classification was “clear”; 76 (93%) affirmed that the app helped them when consulting their physician for their BP evaluation. Majority (87%) perceived the software to be reliable. Furthermore, 71 (87%) said they trust the system and 51 (62%) declared that performing HBPM and self-interpret their readings was “reassuring” whereas 6 (7%) felt that it was “a concern”.Conclusion: This study shows that the majority (88%) of pregnant women performed HBPM and successfully used the Hy-Result software for self-interpretation of the BP readings. The use of the validated Hy-Result system by pregnant women may thus be recommended in common practice by healthcare professionals and patient associations.Keywords: hypertension, home blood pressure monitoring, health informatics, pregnancy, e-health, telemedicine, self-monitoring

Purpose We aimed to identify prognostic factors for survival and long-term intellectual and developmental outcome in neonatal patients with early-onset urea cycle disorders (UCD) experiencing hyperammonaemic coma. Methods We retrospectively analysed ammonia (NH3) and glutamine levels, electroencephalogram and brain images obtained during neonatal coma of UCD patients born between 1995 and 2011 and managed at a single centre and correlated them to survival and intellectual and developmental outcome. Results We included 38 neonates suffering from deficiencies of argininosuccinate synthetase (ASSD, N = 12), ornithine transcarbamylase (OTCD, N = 10), carbamoylphosphate synthetase 1 (CPSD, N = 7), argininosuccinate lyase (ASLD, N = 7), N-acetylglutamate synthase (NAGS, N = 1) or arginase (ARGD, N = 1). Symptoms occurred earlier in mitochondrial than in cytosolic UCD. Sixty-eight percent of patients survived, with a mean (standard deviation-SD) follow-up of 10.4 (5.3) years. Mortality was mostly observed in OTCD (N = 7/10) and CPSD (N = 4/7) patients. Plasma NH3 level during the neonatal period, expressed as area under the curve, but not glutamine level was associated with mortality (p = .044 and p = .610). 62.1% of the patients had normal intellectual and developmental outcome. Intellectual and developmental outcome tended to correlate with UCD subtype (p = .052). No difference in plasma NH3 or glutamine level during the neonatal period among developmental outcomes was identified. EEG severity was linked to UCD subtypes (p = .004), ammonia levels (p = .037), duration of coma (p = .043), and mortality during the neonatal period (p = .020). Status epilepticus was recorded in 6 patients, 3 of whom died neonatally, 1 developed a severe intellectual disability while the 2 last patients had a normal development. Conclusion UCD subtypes differed by survival rate, intellectual and developmental outcome and EEG features in the neonatal period. Hyperammonaemia expressed as area under the curve was associated with survival but not with intellectual and developmental outcome whereas glutamine was not associated with one of these outcomes. Prognostic value of video-EEG monitoring and the association between status epilepticus and mortality should be assessed in neonatal hyperammonaemic coma in further studies.

Previous reports suggest initial presentation of IgA nephropathy (IgAN) in children is different from adults. No systematic comparison of clinical, biological, and histological childhood- and adult-onset IgAN is currently available. We compared pediatric and adult clinical and histological characteristics at IgAN diagnosis. Data on 211 consecutive patients from two different centers in Paris (82 children, 129 adults) were reviewed. Kidney biopsies were scored for Oxford classification and podocytopathic (P1) features. We report higher eGFR at diagnosis in children compared to adults (89.5 vs. 64 ml/min/1.73 m2; p = 0.0001) but no difference in proteinuria. Histological analysis of kidney biopsy found higher proportions of mesangial (M1) and endocapillary (E1) hypercellularity in children compared with adults (M1 [80.7% vs. 27.9%, p = 0.0001]; E1 [71.3% vs. 30%, p = 0.0001]). Focal glomerulosclerosis (S1), tubular atrophy/interstitial fibrosis ≥ 25% (T1), and P1 were more frequent in adults (S1 [81.5% vs. 61.3%, p = 0.0012], T1 [49.5% vs. 1.35%, p = 0.0001], P1 [33.8% vs. 16.4%, p = 0.008). Proteinuria associated with M1, E1, and C1 in children (M1, p = 0.0001; E1, p = 0.0005; C1, p = 0.0014) but S1, P1, and T1 in adults (S1, p = 0.0001; P1, p = 0.0001; T1, p = 0.001). After steroid treatment (41 children and 28 adults), proteinuria decreased in children (p < 0.001, follow-up 38 months) and adults (p < 0.001, follow-up 76.9 months), whereas eGFR remained stable in adults but increased significantly in children (90.6 to 110 ml/min/1.73m2). Proteinuria in children with IgAN is a marker of glomerular proliferative lesions whereas its presence in adults often reflects the presence of chronic lesions. This suggests the need for histological assessment.

Organ transplantation is discussed in methylmalonic aciduria (MMA) for renal failure, and poor quality of life and neurological outcome. We retrospectively evaluated 23 French MMA patients after kidney (KT), liver-kidney (LKT), and liver transplantation (LT). Two patients died, one after LKT, one of hepatoblastoma after KT. One graft was lost early after KT. Of 18 evaluable patients, 12 previously on dialysis, 8 underwent KT (mean 12.5 years), 8 LKT (mean 7 years), and 2 LT (7 and 2.5 years). At a median follow-up of 7.3 (KT), 2.3 (LKT), and 1.0 years (LT), no metabolic decompensation occurred except in 1 KT. Plasma and urine MMA levels dramatically decreased, more after LKT. Protein intake was increased more significantly after LKT than KT. Enteral nutrition was stopped in 7/8 LKT, 1/8 KT. Early complications were frequent after LKT. Neurological disorders occurred in four LKT, reversible in one. Five years after KT, four patients had renal failure. The metabolic outcomes were much better after LKT than KT. LKT in MMA is difficult but improves the quality of life. KT will be rarely indicated. We need more long-term data to indicate early LT, in the hope to delay renal failure and prevent neurodevelopmental complications.

Item does not contain fulltext Infantile nephropathic cystinosis (INC) is an inheritable lysosomal storage disorder characterized by lysosomal cystine accumulation, progressive kidney disease, and multiple extrarenal complications (ERCs). Cysteamine postpones the onset of end-stage kidney disease (ESKD) and reduces the incidence of ERCs; however, cysteamine is generally initiated upon establishment of the renal Fanconi syndrome (FS) and partial loss of kidney function, whereas data on long-term effects of cysteamine administered from neonatal age are lacking. An international multicenter retrospective cohort study of siblings with INC was set up to investigate the outcome in relation to age at initiation of cysteamine versus CTNS genotype, with attention to patients treated with cysteamine from neonatal age. None of the siblings treated from neonatal age (n = 9; age 10 ± 6 years) had reached ESKD, while 22% of their index counterparts (n = 9; age 14 ± 5 years) had commenced renal replacement therapy. Siblings treated with cysteamine from the onset of symptoms at a younger age compared with their index counterparts, reached ESKD at a significant older age (13 ± 3 vs. 10 ± 3 years, p = 0.002). In contrast, no significant difference in ERCs was observed between sibling and index patients, independently from the age at initiation of cysteamine. The CTNS genotype had no impact on the overall outcome in this cohort. In INC, presymptomatic treatment with cysteamine results in a better renal outcome in comparison to treatment initiated from the onset of symptoms. This justifies including cystinosis into newborn screening programs. SYNOPSIS: In infantile nephropathic cystinosis, presymptomatic treatment with cysteamine improves the renal outcome which justifies the inclusion of cystinosis into newborn screening programs. 01 januari 2023

Background Patients with maple syrup urine disease (MSUD) experiencing metabolic decompensations have traditionally been treated with branched-chain amino acid (BCAA)-free mixture via oral or nasogastric administration routes. In some patients, enteral administration is not possible, either because the patient presents with vomiting, coma, or refuses nasogastric administration, thus intravenous (IV) BCAA-free solution is an appropriate intervention for these challenging cases. Aims This study aimed to evaluate the effectiveness and safety of managing metabolic decompensations by administering an IV BCAA-free solution. Methods This is an observational prospective study of data from MSUD patients hospitalised for decompensation episodes between 2010 and 2016 at 6 centres for rare metabolic diseases in France. Results A total of 24 patients (16 males; 8 females) experiencing 126 MSUD metabolic decompensation episodes (39 in children; 87 in adults) were admitted to hospital. At presentation, mean leucine plasma concentration was ≥ 381 µmol/L in 113/126 (89.7%) episodes. Children were treated with continuous IV BCAA-free solution at doses of 0.8 to 2.0 g/kg/day, for 4.8 days and adults for 3.8 days at doses of 0.5 to 2.6 g/kg/day. In the efficacy set of 102 analysable episodes leucine concentrations were normalised (to below 381 µmol/L) in 82% (n = 18/22) of episodes in children and in 84% (n = 67/80) of episodes in adults. Mean time to leucine normalisation was 3.0 days. This was significantly (p Conclusion The IV BCAA-free solution is safe and effective in normalising leucine concentrations during MSUD decompensation episodes in both children and adults, offering a practical treatment alternative for those patients who cannot receive BCAA-free mixture via oral or nasogastric routes.

Background Patients on maintenance haemodialysis (HD) have an increased risk of severe coronavirus disease 2019 (COVID-19) and a reduced response to vaccines. Data are needed to identify immune correlates of protection in this population. Methods Following a COVID-19 outbreak among vaccinated patients in a HD unit, clinical data and serological response to BNT162b2 vaccine were retrospectively recorded. Results Among 53 patients present in the dialysis room, 14 were infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) alpha variant (COVID_Pos) and 39 were not. Compared with uninfected patients, COVID_Pos patients more frequently had additional causes of immunosuppression (50% versus 21%; P = .046) and were more often scheduled on the Monday–Wednesday–Friday (MWF) shift (86% versus 39%; P = .002). Moreover, COVID_Pos had lower anti-spike (S) immunoglobulin G (IgG) titres than uninfected patients {median 24 BAU/mL [interquartile range (IQR) 3–1163] versus 435 [99–2555]; P = .001} and lower neutralization titres [median 108 (IQR 17–224) versus 2483 (481–43 908); P = .007]. Anti-S and neutralization antibody titres are correlated (r = 0.92, P 284 BAU/mL got infected. Ten of 14 COVID_Pos patients were treated with casirivimab and imdevimab. No patient developed severe disease. Conclusions Anti-S IgG titre measured prior to exposure correlates to protection from SARS-CoV-2 infection in HD patients. BNT162b2 vaccination alone or in combination with monoclonal antibodies prevented severe COVID-19.

Nephropathic cystinosis is a rare disease secondary to recessive mutations of the CTNS gene encoding the lysosomal cystine transporter cystinosin, causing accumulation of cystine in multiple organs. Over the years, the disease has evolved from being a fatal condition during early childhood into a treatable condition, with patients surviving into adulthood. Data on cystinosis are limited by the rarity of the disease. Here, we have investigated factors associated with kidney and growth outcome in a very large cohort of 453 patients born between 1964 and 2016 and followed in Belgium, Germany, Austria, France, Italy, Spain, The Netherlands, Turkey and United Kingdom. From the 1970s to the 1990s, the median increase in kidney survival was 9.1 years. During these years, cysteamine, a cystine-depleting agent, was introduced for the treatment of cystinosis. Significant risk factors associated with early progression to end-stage kidney disease assessed by Cox proportional multivariable analysis included delayed initiation of cysteamine therapy and higher mean leucocyte cystine levels. No significant effect on kidney function was observed for gender, pathogenic variant of the CTNS gene, and the prescription of indomethacin or renin angiotensin system blockers. Significantly improved linear growth was associated with early use of cysteamine and lower leukocyte cystine levels. Thus, our study provides strong evidence in favor of early diagnosis and optimization of cystine depletion therapy in nephropathic cystinosis.

Despite improvement in the specific treatment, clinical and anatomo-functional central nervous system (CNS) abnormalities of various severities are still observed in cystinosis patients. Patients who develop CNS complications today have a worse compliance to cysteamine treatment. Radiological studies have shown that cortical or central (ventriculomegaly) atrophy is observed in more than two thirds of cystinosis patients’ magnetic resonance imaging (MRI) and correlates with the intelligence quotient score. Half of cystinosis patients have marked aspecific white matter hyperintensities. The development of advanced neuroimaging techniques provides new tools to further investigate CNS complications. A recent neuroimaging study using a voxel-based morphometry approach showed that cystinosis patients present a decreased grey matter volume in the left middle frontal gyrus. Diffusion tensor imaging studies have shown white matter microstructure abnormalities in children and adults with cystinosis, respectively in areas of the dorsal visual pathway and within the corpus callosum’s body. Finally, leucocyte cystine levels are associated with decreased resting cerebral blood flow, measured by arterial spin labelling, in the frontal cortex, which could be associated with the neurocognitive deficits described in these patients. These results reinforce the relevance of neuroimaging studies to further understand the mechanisms that underline CNS impairments.

C3 glomerulopathy (C3G) is a rare complement-mediated disease. Specific treatments are not yet available and factors predictive of kidney survival such as age, kidney function and proteinuria are not specific to C3G. The prognostic value of biomarkers of complement activation, which are pathognomonic of the diseases, remains unknown. In a large cohort of 165 patients from the French National registry, we retrospectively assess the prognostic value of C3, soluble C5b-9 (sC5b-9), C3 nephritic factor, and rare disease-predicting variants in complement genes in predicting clinical outcome of patients. By multivariate analysis age (adult onset), reduced kidney function (defined by estimated glomerular filtration rate under 60ml/min) and presence of rare disease-predicting variants in complement genes predicted risk of progression to kidney failure. Moreover, by multivariate analysis, normal C3/high sC5b-9 levels or low C3/normal sC5b-9 levels remained independently associated with a worse kidney prognosis, with the relative risk 3.7- and 8-times higher, respectively. Subgroup analysis indicated that the complement biomarker profiles independently correlated to kidney prognosis in patients with adult but not pediatric onset. In this subgroup, we showed that profiles of biomarkers C3 and/or sC5b-9 correlated with intra glomerular inflammation and may explain kidney outcomes. In children, only the presence of rare disease-predicting variants correlated with kidney survival. Thus, in an adult population, we propose a three-point C3G prognostic score based on biomarker profiles at risk, estimated glomerular filtration rate at presentation and genetic findings, which may help stratify adult patients into subgroups that require close monitoring and more aggressive therapy.

International audience; Background Atypical hemolytic uremic syndrome (HUS) is associated with high recurrence rates after kidney transplant, with devastating outcomes. In late 2011, experts in France recommended the use of highly individualized complement blockade-based prophylaxis with eculizumab to prevent post-transplant atypical HUS recurrence throughout the country.Methods To evaluate this strategy's effect on kidney transplant prognosis, we conducted a retrospective multicenter study from a large French nationwide registry, enrolling all adult patients with atypical HUS who had undergone complement analysis and a kidney transplant since January 1, 2007. To assess how atypical HUS epidemiology in France in the eculizumab era evolved, we undertook a population-based cohort study that included all adult patients with atypical HUS (n=397) between 2007 and 2016.Results The first study included 126 kidney transplants performed in 116 patients, 58.7% and 34.1% of which were considered to be at a high and moderate risk of atypical HUS recurrence, respectively. Eculizumab prophylaxis was used in 52 kidney transplants, including 39 at high risk of recurrence. Atypical HUS recurred after 43 (34.1%) of the transplants; in four cases, patients had received eculizumab prophylaxis and in 39 cases they did not. Use of prophylactic eculizumab was independently associated with a significantly reduced risk of recurrence and with significantly longer graft survival. In the second, population-based cohort study, the proportion of transplant recipients among patients with ESKD and atypical HUS sharply increased between 2012 and 2016, from 46.2% to 72.3%, and showed a close correlation with increasing eculizumab use among the transplant recipients.Conclusions Results from this observational study are consistent with benefit from eculizumab prophylaxis based on pretransplant risk stratification and support the need for a rigorous randomized trial.

Cystinosis is an autosomal recessive storage disease due to impaired transport of cystine out of lysosomes. Since the accumulation of intracellular cystine affects all organs and tissues, the management of cystinosis requires a specialized multidisciplinary team consisting of pediatricians, nephrologists, nutritionists, ophthalmologists, endocrinologists, neurologists' geneticists, and orthopedic surgeons. Treatment with cysteamine can delay or prevent most clinical manifestations of cystinosis, except the renal Fanconi syndrome. Virtually all individuals with classical, nephropathic cystinosis suffer from cystinosis metabolic bone disease (CMBD), related to the renal Fanconi syndrome in infancy and progressive chronic kidney disease (CKD) later in life. Manifestations of CMBD include hypophosphatemic rickets in infancy, and renal osteodystrophy associated with CKD resulting in bone deformities, osteomalacia, osteoporosis, fractures, and short stature. Assessment of CMBD involves monitoring growth, leg deformities, blood levels of phosphate, electrolytes, bicarbonate, calcium, and alkaline phosphatase, periodically obtaining bone radiographs, determining levels of critical hormones and vitamins, such as thyroid hormone, parathyroid hormone, 25(OH) vitamin D, and testosterone in males, and surveillance for nonrenal complications of cystinosis such as myopathy. Treatment includes replacement of urinary losses, cystine depletion with oral cysteamine, vitamin D, hormone replacement, physical therapy, and corrective orthopedic surgery. The recommendations in this article came from an expert meeting on CMBD that took place in Salzburg, Austria, in December 2016. ispartof: JOURNAL OF INHERITED METABOLIC DISEASE vol:42 issue:5 pages:1019-1029 ispartof: location:United States status: published

Background Hypocomplementemic urticarial vasculitis (HUV) is a rare systemic vasculitis. We aimed to describe the kidney involvement of HUV in a multicenter national cohort with an extended follow-up. Methods All patients with HUV (international Schwartz criteria) with a biopsy-proven kidney involvement, identified through a survey of the French Vasculitis Study Group (FVSG), were included. A systematic literature review on kidney involvement of HUV was performed. Results Twelve patients were included, among whom 8 had positive anti-C1q antibodies. All presented with proteinuria, from mild to nephrotic, and 8 displayed acute kidney injury (AKI), requiring temporary haemodialysis in 2. Kidney biopsy showed membrano-proliferative glomerulonephritis (MPGN) in 8 patients, pauci-immune crescentic GN or necrotizing vasculitis in 3 patients (with a mild to severe interstitial inflammation), and an isolated interstitial nephritis in 1 patient. C1q deposits were observed in the glomeruli (n = 6), tubules (n = 4) or renal arterioles (n = 3) of 8 patients. All patients received corticosteroids, and 9 were also treated with immunosuppressants or apheresis. After a mean follow-up of 8.9 years, 6 patients had a preserved renal function, but 2 patients had developed stage 3–4 chronic kidney disease (CKD) and 4 patients had reached end-stage kidney disease (ESKD), among whom 1 had received a kidney transplant. Conclusion Renal involvement of HUV can be responsible for severe AKI, CKD and ESRD. It is not always associated with circulating anti-C1q antibodies. Kidney biopsy shows mostly MPGN or crescentic GN, with frequent C1q deposits in the glomeruli, tubules or arterioles.

BACKGROUND: Urea cycle disorders (UCD) are rare diseases that usually affect neonates or young children. During decompensations, hyperammonemia is neurotoxic, leading to severe symptoms and even coma and death if not treated rapidly. AIMS: Description of a cohort of patients with adult onset of UCDs. METHODS: Multicentric, retrospective and descriptive study of French adult patients with a diagnosis after 16 years of age of UCDs due to a deficiency in one of the 6 enzymes (arginase, ASL, ASS, CPS1, NAGS, OTC) or the two transporters (ORNT1 or citrin). RESULTS: Seventy-one patients were included (68% female, 32% male). The diagnosis was made in the context of (i) a metabolic decompensation (42%), (ii) family history (55%), or (iii) chronic symptoms (3%). The median age at diagnosis was 33 years (range 16-86). Eighty-nine percent of patients were diagnosed with OTC deficiency, 7% CPS1 deficiency, 3% HHH syndrome and 1% argininosuccinic aciduria. For those diagnosed during decompensations (including 23 OTC cases, mostly female), 89% required an admission in intensive care units. Seven deaths were attributed to UCD - 6 decompensations and 1 epilepsy secondary to inaugural decompensation. CONCLUSION: This is the largest cohort of UCDs diagnosed in adulthood, which confirms the triad of neurological, gastrointestinal and psychiatric symptoms during hyperammonemic decompensations. We stress that females with OTC deficiency can be symptomatic. With 10% of deaths in this cohort, UCDs in adults remain a life-threatening condition. Physicians working in adult care must be aware of late-onset presentations given the implications for patients and their families. This article is protected by copyright. All rights reserved.