Physical fitness in children and adolescents with inflammatory bowel disease: protocol for a case-control study.

INTRODUCTION: Inflammatory bowel disease (IBD) is a chronic disorder of the gastrointestinal tract, associated with adverse health consequences that may adversely influence physical activity and body composition in youth. These effects may lead to changes in physical fitness, which is positively associated with health-related outcomes. The aim is to assess health-related physical fitness levels in paediatric patients with IBD and to compare these levels with those in healthy matched controls. METHODS AND ANALYSIS: This trial is a bicentric case-control study. Fifty paediatric patients with IBD and 50 matched healthy controls will be recruited (1:1), and physical fitness levels (cardiorespiratory fitness, muscular strength, speed/agility and flexibility) will be assessed. The primary outcome is cardiorespiratory fitness, which will be compared between children and adolescents with IBD and healthy controls matched for age, sex and body mass index class. We will assess whether the two groups differ with respect to other physical fitness components and cardiovascular risk in adulthood according to sex-specific cut-offs for a healthy cardiorespiratory fitness level in adolescents. We will identify relationships between physical fitness and characteristics of IBD, quality of life and daily physical activity. ETHICS AND DISSEMINATION: This study was approved by the Research Ethics Committee (Comité de Protection des Personnes, Centre-Ouest I, Tours, France; No 2019-A02651-56) and was declared to the Commission Nationale de l'Informatique et des Libertés. All procedures will be performed according to the ethical standards of the 1975 Declaration of Helsinki, as revised in 2008, and the European Union's Guidelines for Good Clinical Practice. Written informed consent will be obtained from the youths and their parents. Research findings will be disseminated in peer-reviewed journals and scientific meetings, as well as in social media and IBD family support groups. TRIAL REGISTRATION NUMBER: NCT04647578.

Management of Central Venous Catheters in Children and Adults on Home Parenteral Nutrition: A French Survey of Current Practice.

Although central venous catheter (CVC)-related thrombosis (CRT) is a severe complication of home parenteral nutrition (HPN), the amount and quality of data in the diagnosis and management of CRT remain low. We aimed to describe current practices regarding CVC management in French adult and pediatric HPN centers, with a focus on CVC obstruction and CRT. Current practices regarding CVC management in patients on HPN were collected by an online-based cross-sectional survey sent to expert physicians of French HPN centers. We compared these practices to published guidelines and searched for differences between pediatric and adult HPN centers' practices. Finally, we examined the heterogeneity of practices in both pediatric and adult HPN centers. The survey was completed by 34 centers, including 21 pediatric and 13 adult centers. We found a considerable heterogeneity, especially in the responses of pediatric centers. On some points, the centers' responses differed from the current guidelines. We also found significant differences between practices in adult and pediatric centers. We conclude that the management of CVC and CRT in patients on HPN is a serious and complex situation for which there is significant heterogeneity between HPN centers. These findings highlight the need for more well-designed clinical trials in this field.

Feeding disorders in children with oesophageal atresia: a cross-sectional study.

INTRODUCTION: With advances in surgical and neonatal care, the survival of patients with oesophageal atresia (OA) has improved over time. Whereas a number of OA-related conditions (delayed primary anastomosis, anastomotic stricture and oesophageal dysmotility) may have an impact on feeding development and although children with OA experience several oral aversive events, paediatric feeding disorders (PFD) remain poorly described in this population. The primary aim of our study was to describe PFD in children born with OA, using a standardised scale. The secondary aim was to determine conditions associated with PFD. METHODS: The Feeding Disorders in Children with Oesophageal Atresia Study is a national cohort study based on the OA registry from the French National Network. Parents of children born with OA between 2013 and 2016 in one of the 22 participating centres were asked to complete the French version of the Montreal Children's Hospital Feeding Scale. RESULTS: Of the 248 eligible children, 145 children, with a median age of 2.3 years (Q1-Q3 1.8-2.9, min-max 1.1-4.0 years), were included. Sixty-one children (42%) developed PFD; 13% were tube-fed (n=19). Almost 40% of children with PFD failed to thrive (n=23). The presence of chronic respiratory symptoms was associated with the development of PFD. Ten children with PFD (16%) had no other condition or OA-related complication. CONCLUSION: PFD are common in children with OA, and there is no typical profile of patients at risk of PFD. Therefore, all children with OA require a systematic screening for PFD that could improve the care and outcomes of patients, especially in terms of growth.

Renal Prognosis in Children With Tubulointerstitial Nephritis and Uveitis Syndrome.

INTRODUCTION: Tubulointerstitial nephritis (TIN) and uveitis (TINU) syndrome is a rare disease. The renal prognosis is generally thought to be better in children with TINU syndrome than in adults. However, data are scarce. We aimed to investigate the long-term renal prognosis in a French cohort of children with TINU syndrome. METHODS: We performed a national retrospective study including 23 French pediatric nephrology centers enrolling patients with TINU syndrome diagnosed between January 2000 and December 2018. RESULTS: A total of 46 patients were included (52% female, median age 13.8 years). At diagnosis of TIN, the median estimated glomerular filtration rate (eGFR) was 30.6 ml/min per 1.73 m2 (4.9-62.8). The median time between diagnosis of uveitis and TIN was 0.4 months (-4.1; +17.1). All patients had anterior uveitis, but 12 (29%) were asymptomatic. Nearly all patients (44 of 46) received steroid treatment, and 12 patients (26%) received a second-line therapy. At last follow-up (median 2.8 years), the median eGFR was 87.5 ml/min per 1.73 m2 (60.3-152.7) and <90 ml/min per 1.73 m2 in 20 patients. CONCLUSION: In our study, nearly half of the patients had renal sequelae at last follow-up. Given the possible progression to chronic kidney disease, long-term monitoring of children with TINU syndrome is mandatory. Approximately a quarter of the children had asymptomatic uveitis suggesting all children presenting with TIN should undergo systematic ophthalmologic screening even in the absence of ocular signs.

Functional abdominal pain disorders and patient- and parent-reported outcomes in children with inflammatory bowel disease in remission.

BACKGROUND: Chronic abdominal pain occurs frequently in pediatric patients with inflammatory bowel disease (IBD) in remission. AIMS: To assess the prevalence and factors associated with Functional Abdominal Pain Disorders among IBD children in remission (IBD-FAPD). METHODS: Patients with IBD for > 1 year, in clinical remission for ≥ 3 months were recruited from a National IBD network. IBD-FAPDs were assessed using the Rome III questionnaire criteria. Patient- or parent- reported outcomes were assessed. RESULTS: Among 102 included patients, 57 (56%) were boys, mean age (DS) was 15.0 (± 2.0) years and 75 (74%) had Crohn's disease. Twenty-two patients (22%) had at least one Functional Gastrointestinal Disorder among which 17 had at least one IBD-FAPD. Past severity of disease or treatments received and level of remission were not significantly associated with IBD-FAPD. Patients with IBD-FAPD reported more fatigue (peds-FACIT-F: 35.9 ± 9.8 vs. 43.0 ± 6.9, p = 0.01) and a lower HR-QoL (IMPACT III: 76.5 ± 9.6 vs. 81.6 ± 9.2, p = 0.04) than patients without FAPD, and their parents had higher levels of State and Trait anxiety than the other parents. CONCLUSIONS: Prevalence of IBD-FAPD was 17%. IBD-FAPD was not associated with past severity of disease, but with fatigue and lower HR-QoL.

Eculizumab discontinuation in children and adults with atypical hemolytic-uremic syndrome: a prospective multicenter study.

The optimal duration of eculizumab treatment in patients with atypical hemolytic uremic syndrome (aHUS) remains poorly defined. We conducted a prospective national multicenter open-label study to assess eculizumab discontinuation in children and adults with aHUS. Fifty-five patients (including 19 children) discontinued eculizumab (mean treatment duration, 16.5 months). Twenty-eight patients (51%) had rare variants in complement genes, mostly in MCP (n = 12; 22%), CFH (n = 6; 11%), and CFI (n = 6; 10%). At eculizumab discontinuation, 17 (30%) and 4 patients (7%) had stage 3 and 4 chronic kidney disease, respectively. During follow-up, 13 patients (23%; 6 children and 7 adults) experienced aHUS relapse. In multivariable analysis, female sex and presence of a rare variant in a complement gene were associated with an increased risk of aHUS relapse, whereas requirement for dialysis during a previous episode of acute aHUS was not. In addition, increased sC5b-9 plasma level at eculizumab discontinuation was associated with a higher risk of aHUS relapse in all patients and in the subset of carriers with a complement gene rare variant, both by log-rank test and in multivariable analysis. Of the 13 relapsing patients, all of whom restarted eculizumab, 11 regained their baseline renal function and 2 had a worsening of their preexisting chronic kidney disease, including 1 patient who progressed to end-stage renal disease. A strategy of eculizumab discontinuation in aHUS patients based on complement genetics is reasonable and safe. It improves the management and quality of life of a sizeable proportion of aHUS patients while reducing the cost of treatment. This trial was registered at www.clinicaltrials.gov as #NCT02574403.

Effects of upper airway obstruction or hypoxia on gastroesophageal reflux in newborn lambs.

BACKGROUND: Although it is commonly accepted that upper airway obstruction (UAO) increases gastroesophageal reflux (GER), the link is poorly understood and insufficiently documented. In addition, while hypoxia is often encountered in infants with UAO, its consequences on GER are virtually unknown. The two aims of the present study were to characterize the effects of (1) UAO and (2) hypoxia on GER. METHODS: Seventeen lambs underwent polysomnographic and esophageal impedance/pH-metry monitoring during UAO vs. a control condition (6 h, ten lambs) or 10% hypoxia vs. normoxic condition (3 h, seven other lambs). RESULTS: Moderate-to-severe UAO was maintained throughout monitoring (inspiratory tracheal pressure of -13 (-15, -12) cm H2O vs. -1 (-1, -1) cm H2O in control condition, p = 0.005). While the number of GERs increased with UAO (2 (1, 4) vs. 0 (0, 3) in the control condition, p = 0.03), the increase was less than anticipated and inconsistent among the lambs. Also, sustained 10% hypoxia did not alter the number of GERs (2 (1, 3) vs. 0 (0, 5) in the control condition, p = 0.9). CONCLUSIONS: The presence of an UAO for 6 h mildly increased the number of GERs, whereas hypoxia for 3 h had no significant effect. IMPACT: The effect of upper airway obstruction and hypoxia on gastroesophageal reflux is poorly documented in the neonatal period. A moderate-to-severe upper airway obstruction for 6 h results in a mild, inconsistent increase in the number of gastroesophageal refluxes. Overall, a hypoxia of 10% for 3 h had no significant impact on gastroesophageal reflux. The prescription of an antireflux medication in infants with upper airway obstruction must not be systematic but rely on objective signs of a pathologic gastroesophageal reflux.

Efficacy and safety of intravenous immunoglobulin with rituximab versus rituximab alone in childhood-onset steroid-dependent and frequently relapsing nephrotic syndrome: protocol for a multicentre randomised controlled trial.

INTRODUCTION: Guidelines for the treatment of steroid-dependent nephrotic syndrome (SDNS) and frequently relapsing nephrotic syndrome (FRNS) are lacking. Given the substantial impact of SDNS/FRNS on quality of life, strategies aiming to provide long-term remission while minimising treatment side effects are needed. Several studies confirm that rituximab is effective in preventing early relapses in SDNS/FRNS; however, the long-term relapse rate remains high (~70% at 2 years). This trial will assess the association of intravenous immunoglobulins (IVIgs) to rituximab in patients with SDNS/FRNS and inform clinicians on whether IVIg's immunomodulatory properties can alter the course of the disease and reduce the use of immunosuppressive drugs and their side effects. METHODS AND ANALYSIS: We conduct an open-label multicentre, randomised, parallel group in a 1:1 ratio, controlled, superiority trial to assess the safety and efficacy of a single infusion of rituximab followed by IVIg compared with rituximab alone in childhood-onset FRNS/SDNS. The primary outcome is the occurrence of first relapse within 24 months. Patients are allocated to receive either rituximab alone (375 mg/m²) or rituximab followed by IVIg, which includes an initial Ig dose of 2 g/kg, followed by 1.5 g/kg injections once a month for the following 5 months (maximum dose: 100 g). ETHICS AND DISSEMINATION: The study has been approved by the ethics committee (Comité de Protection des Personnes) of Ouest I and authorised by the French drug regulatory agency (Agence Nationale de Sécurité du Médicament et des Produits de Santé). Results of the primary study and the secondary aims will be disseminated through peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT03560011.

Protocol of a randomised controlled trial assessing the impact of physical activity on bone health in children with inflammatory bowel disease.

INTRODUCTION: Low bone mineral density (BMD) is a frequent issue in children and adolescents with inflammatory bowel disease (IBD). Several studies in healthy populations have reported a positive impact of physical activity (PA) on bone health. Recently, an observational study in paediatric patients with IBD showed a significant positive relationship between daily PA and BMD. However, intervention studies investigating a causal relationship between PA and BMD are warranted to confirm these results. The aim of this randomised controlled trial will be to investigate the effect of a PA programme on BMD in paediatric patients with IBD. METHODS AND ANALYSIS: This trial is a multicentre (four centres), randomised, controlled, blinded end-point study. Eighty children with IBD will be randomly assigned in a 1:1 ratio to receive a programme with adapted physical exercises (intervention group) or usual PA (control group) during a 9-month period. The primary outcome is the change from baseline at 9 months (the end of the study) in whole-body BMD assessed by dual-energy X-ray absorptiometry. Secondary efficacy outcomes include the changes from baseline at 9 months in: BMD assessed in the lumbar spine and trochanter; daily PA (time spent in moderate-to-vigorous PA); body composition (fat mass and fat-free mass); fatigue resistance; quality of life and activity of IBD. ETHICS AND DISSEMINATION: The study was approved by the Research Ethics Committee in France (Comité de Protection des Personnes, Sud-Ouest and Outre-Mer III, Bordeaux, France, No 2018/27). All procedures will be performed according to the ethical standards of the Helsinki Declaration of 1975, as revised in 2008, and the European Union's Guidelines for Good Clinical Practice. Written informed consent will be obtained from the parents or legal guardian and from the children. Research findings will be disseminated in peer-reviewed journals and scientific meetings. TRIAL REGISTRATION NUMBER: NCT03774329.

Physical activity is associated with improved bone health in children with inflammatory bowel disease.

BACKGROUND & AIMS: Bone health is an important concern in patients with inflammatory bowel disease (IBD). Low bone mineral density (BMD) is a powerful predictor of fracture risk in IBD patients. Physical activity (PA) plays an important role in bone health. However, PA data for children and adolescents with IBD are scarce. The primary aim is to evaluate the relationship between PA and BMD in children with IBD. The secondary aim was to assess the relationship between PA and quality of life. METHODS: Eighty-four IBD paediatric patients (45 boys) aged 14.3 ± 2.7 years were included (disease activity: (i) remission, n = 62; (ii) mild, n = 18; (iii) severe disease, n = 1). BMD was measured using dual-energy X-ray absorptiometry and expressed as age- and sex-based Z-scores. Each patient wore a triaxial accelerometer for seven consecutive days for objective PA quantification. Quality of life was assessed using the PedsQL™ and energy intake was assessed prospectively for three days using a dietary diary. RESULTS: BMD Z-score was -0.96 ± 1.11. Only five patients (6%) fulfilled the recommendation of 60 min of daily moderate-to-vigorous PA (MVPA). The proportion of children with osteopenia and osteoporosis was 51% and 4%, respectively. After adjustment for confounders (pubertal status and body mass index), total PA and time in MVPA were positively associated with BMD (regression coefficient per one standard deviation increase in PA parameters = 0.26; P < 0.05). There was no association between time spent in MVPA and total PA, and total quality of life score. CONCLUSIONS: PA likely is associated with improved bone health in IBD children. Intervention studies investigating a causal relationship between PA and BMD in paediatric patients with IBD are warranted.

Long-term outcome of pediatric-onset Crohn's disease: A population-based cohort study.

BACKGROUND: Pediatric-onset Crohn's disease (CD) may represent a more severe form of disease. The aim of this study was to describe long-term outcome and identify associated risk factors of complicated behavior in a large population-based pediatric-onset CD cohort. PATIENTS AND METHODS: Cases included all patients recorded in the EPIMAD registry diagnosed with definite or probable CD between January 1988 and December 2004, under the age of 17 years at the time of diagnosis, with at least two years of follow-up. RESULTS: Five hundred and thirty-five patients were included. Median follow-up was 11.1 years [IQR, 7.3-15.0]. At the end of follow-up, 8% (n = 44) of patients had pure ileal disease (L1), 8% (n = 44) had pure colonic disease (L2), and 83% (n = 439) had ileocolonic disease (L3). L4 disease and perianal disease were observed in 42% (n = 227) and 16% (n = 85) of patients, respectively. At the end of follow-up, 58% (n = 308) of patients presented complicated disease behavior (B2, 39% and B3, 19%), and 42% (n = 163) of patients with inflammatory behavior at diagnosis had evolved to complicated behavior. During follow-up, 86% of patients (n = 466) received at least one course of corticosteroids, 67% (n = 357) of patients had been exposed to immunosuppressants and 35% (n = 187) of patients received at least one anti-TNF agent. Forty-three percent (n = 230) of patients underwent at least one intestinal resection. The overall mortality rate was 0.93% and the SMR was 1.6 [0.5-3.8] (p = 0.20). Five cancers were reported with a crude cancer incidence rate of 1.1% and an SIR of 3.3 [1.2-7.0] (p = 0.01). In a multivariate Cox model, ileal (HR, 1.87 [1.09-3.21], p = 0.022) or ileocolonic (HR, 1.54 [1.01-2.34], p = 0.042) and perianal lesions at diagnosis (HR, 1.81 [1.13- 2.89], p = 0.013) were significantly associated with complicated behavior. CONCLUSION: About 80% of patients with pediatric-onset CD presented extensive ileocolonic disease during follow-up. The majority of patients evolved to complicated behavior. Surgery, cancer and mortality were observed in 43%, 0.9% and 0.9% of patients, respectively.

Effects of Smoking Exposure in Infants on Gastroesophageal Reflux as a Function of the Sleep-Wakefulness State.

OBJECTIVE: To determine whether perinatal smoking exposure is associated with gastroesophageal reflux (GER)-related changes in sleep-wakefulness states in neonates. STUDY DESIGN: Thirty-one neonates, referred for the investigation of suspected GER, were recruited and underwent multichannel impedance-pH monitoring and synchronized 8- to 12-hour polysomnography. The infants' exposure to tobacco smoke was estimated by means of a urine cotinine assay. The total number, frequency (h-1), and mean duration (minutes) of GER-pH (reflux events detected by the pH electrode only) and GER-imp (reflux events with bolus movement detected by impedance) events were determined. Intergroup differences (smoking-exposed group vs nonexposed group) were probed with nonparametric, unpaired Mann-Whitney U tests. A χ2 test was used to assess a possible intergroup difference in bolus retrograde migration during GER-imp events. RESULTS: According to the urine cotinine assay, 21 of the 31 neonates had been exposed to cigarette smoke during the perinatal period. The number (and frequency) of GER-imp was significantly greater (P = .016) in the exposed group (29 [0-90]) than in the nonexposed group (12 [2-35]). Migration of the esophageal bolus from the distal segment to the most proximal segment was significantly more frequent (P = .016) in the exposed group (83% of GER) than in the nonexposed group (41%). The GER pattern associated with smoking exposure was particularly obvious during Rapid eye movement sleep. CONCLUSIONS: The more frequent occurrence and greater proximal migration of GER-imp in the smoking-exposed group (especially during rapid eye movement sleep) may have clinical relevance. Smoking exposure is a preventable risk factor for limiting the occurrence of GER in neonates.

Nasal high-frequency oscillatory ventilation inhibits gastroesophageal reflux in the neonatal period.

Nasal high-frequency oscillatory ventilation (nHFOV) in neonates is increasingly considered due to enhanced alveolar ventilation, absence of patient-ventilator asynchrony and lessened ventilator-induced lung injury. Although any type of non-invasive respiratory support can lead to gastric distension via esophageal air passage and thus promote gastroesophageal refluxes (GERs), we have shown that nasal continuous positive airway pressure (CPAP; 6 cmH2O) and intermittent positive pressure ventilation (15/4 cmH2O) conversely inhibit GERs in lambs. The current objective was to test the hypothesis that nHFOV also inhibits GERs compared to spontaneous ventilation without respiratory support. Eight lambs underwent five hours of polysomnographic and esophageal multichannel intraluminal impedance pHmetry recordings to assess GERs and air passage into the esophagus, with and without nHFOV (mean airway pressure = 8 cmH2O, oscillation frequency = 8 Hz, amplitude ≈ 20 cmH2O and I:E = 1:2). Results revealed that GERs were decreased with nHFOV (p = .03), despite an increase in gas-containing swallows (p = .01). In conclusion, similarly to nasal CPAP and intermittent positive pressure ventilation, nHFOV inhibits GERs in newborn lambs.

Prevalence of Novel MAGED2 Mutations in Antenatal Bartter Syndrome.

BACKGROUND AND OBJECTIVES: Mutations in the MAGED2 gene, located on the X chromosome, have been recently detected in males with a transient form of antenatal Bartter syndrome or with idiopathic polyhydramnios. The aim of this study is to analyze the proportion of the population with mutations in this gene in a French cohort of patients with antenatal Bartter syndrome. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The French cohort of patients with antenatal Bartter syndrome encompasses 171 families. Mutations in genes responsible for types 1-4 have been detected in 75% of cases. In patients without identified genetic cause (n=42), transient antenatal Bartter syndrome was reported in 12 cases. We analyzed the MAGED2 gene in the entire cohort of negative cases by Sanger sequencing and retrospectively collected clinical data regarding pregnancy as well as the postnatal outcome for positive cases. RESULTS: We detected mutations in MAGED2 in 17 patients, including the 12 with transient antenatal Bartter syndrome, from 16 families. Fifteen different mutations were detected (one whole deletion, three frameshift, three splicing, three nonsense, two inframe deletions, and three missense); 13 of these mutations had not been previously described. Interestingly, two patients are females; in one of these patients our data are consistent with selective inactivation of chromosome X explaining the severity. The phenotypic presentation in our patients was variable and less severe than that of the originally described cases. CONCLUSIONS: MAGED2 mutations explained 9% of cases of antenatal Bartter syndrome in a French cohort, and accounted for 38% of patients without other characterized mutations and for 44% of male probands of negative cases. Our study confirmed previously published data and showed that females can be affected. As a result, this gene must be included in the screening of the most severe clinical form of Bartter syndrome.

Reflex cardiorespiratory events from esophageal origin are heightened by preterm birth.

The involvement of gastroesophageal refluxes in cardiorespiratory events of preterm infants remains controversial. While a few studies in full-term newborn animals have shown that stimulation of esophageal receptors leads to cardiorespiratory reflexes, the latter remain largely unknown, especially after premature birth. The present study aimed to 1) characterize the cardiorespiratory reflexes originating from esophageal receptors in newborn lambs and 2) test the hypotheses that preterm birth enhances reflex cardiorespiratory inhibition and that C-fibers are involved in these reflexes. Eight full-term lambs and 10 lambs born 14 days prematurely were studied. Following surgical instrumentation, a 6-h polysomnography was performed without sedation to record electrocardiogram, respiratory movements, arterial pressure, laryngeal constrictor muscle activity, state of alertness, and hemoglobin oxygen saturation. Five esophageal stimulations of the upper and/or lower esophagus, including rapid balloon inflation and/or HCl injection, were performed in random order. A second recording was performed in full-term lambs 24 h later, after C-fiber blockade by capsaicin. Results confirmed that esophageal stimulations induced inhibitory cardiorespiratory reflexes combined with protective mechanisms, including laryngeal closure, swallowing, coughing, increased arterial pressure, and arousal. Preterm birth heightened cardiorespiratory inhibition. The strongest cardiorespiratory inhibition was observed following simultaneous stimulation of the lower and upper esophagus. Finally, cardiorespiratory inhibition was decreased after C-fiber blockade. In conclusion, esophageal stimulation induces inhibitory cardiorespiratory reflexes, which are partly mediated by C-fibers and more pronounced in preterm lambs. Clinical relevance of these findings requires further studies, especially in conditions associated with increased cardiorespiratory events, e.g., neonatal infection.NEW & NOTEWORTHY Preterm birth heightens the cardiorespiratory events triggered by esophageal stimulation. The most extensive cardiorespiratory events are induced by simultaneous stimulation of the proximal and distal esophagus.

Clinical and Genetic Spectrum of Bartter Syndrome Type 3.

Bartter syndrome type 3 is a clinically heterogeneous hereditary salt-losing tubulopathy caused by mutations of the chloride voltage-gated channel Kb gene (CLCNKB), which encodes the ClC-Kb chloride channel involved in NaCl reabsorption in the renal tubule. To study phenotype/genotype correlations, we performed genetic analyses by direct sequencing and multiplex ligation-dependent probe amplification and retrospectively analyzed medical charts for 115 patients with CLCNKB mutations. Functional analyses were performed in Xenopus laevis oocytes for eight missense and two nonsense mutations. We detected 60 mutations, including 27 previously unreported mutations. Among patients, 29.5% had a phenotype of ante/neonatal Bartter syndrome (polyhydramnios or diagnosis in the first month of life), 44.5% had classic Bartter syndrome (diagnosis during childhood, hypercalciuria, and/or polyuria), and 26.0% had Gitelman-like syndrome (fortuitous discovery of hypokalemia with hypomagnesemia and/or hypocalciuria in childhood or adulthood). Nine of the ten mutations expressed in vitro decreased or abolished chloride conductance. Severe (large deletions, frameshift, nonsense, and essential splicing) and missense mutations resulting in poor residual conductance were associated with younger age at diagnosis. Electrolyte supplements and indomethacin were used frequently to induce catch-up growth, with few adverse effects. After a median follow-up of 8 (range, 1-41) years in 77 patients, chronic renal failure was detected in 19 patients (25%): one required hemodialysis and four underwent renal transplant. In summary, we report a genotype/phenotype correlation for Bartter syndrome type 3: complete loss-of-function mutations associated with younger age at diagnosis, and CKD was observed in all phenotypes.

The dynamics of cardiac autonomic control in sleeping preterm neonates exposed in utero to smoking.

OBJECTIVE: We aimed to determine whether in utero exposure to smoking may influence the activity and dynamics of cardiac autonomic control in preterm infants. We hypothesized that cardiac autonomic control is altered in preterm infants exposed prenatally to smoking and that these effects may vary as a function of the sleep state. METHODS: We studied healthy, preterm neonates born to mothers who had smoked throughout pregnancy but not since birth (n=16). In utero-exposed neonates were matched with control preterm neonates born to non-smoking mothers (n=18). Cardiac autonomic control was monitored as a function of the sleep state by assessing heart rate variability with both linear and non-linear methods. RESULTS: Preterm neonates with in utero exposure to smoking displayed alterations (relative to control neonates) in short-term cardiac autonomic control in all sleep states. These alterations included low vagal activity, elevated sympathetic activity, and low complexity and adaptability in heart rate control dynamics. CONCLUSIONS: Our results constitute direct evidence that cardiac autonomic activity and control are altered in sleeping preterm infants exposed to smoking in utero. SIGNIFICANCE: These alterations may place the affected infants at a higher risk of neurological and cardiovascular complications, which could conceivably persist throughout childhood and adulthood.

Inhibitory Effect of Nasal Intermittent Positive Pressure Ventilation on Gastroesophageal Reflux.

Non-invasive intermittent positive pressure ventilation can lead to esophageal insufflations and in turn to gastric distension. The fact that the latter induces transient relaxation of the lower esophageal sphincter implies that it may increase gastroesophageal refluxes. We previously reported that nasal Pressure Support Ventilation (nPSV), contrary to nasal Neurally-Adjusted Ventilatory Assist (nNAVA), triggers active inspiratory laryngeal closure. This suggests that esophageal insufflations are more frequent in nPSV than in nNAVA. The objectives of the present study were to test the hypotheses that: i) gastroesophageal refluxes are increased during nPSV compared to both control condition and nNAVA; ii) esophageal insufflations occur more frequently during nPSV than nNAVA. Polysomnographic recordings and esophageal multichannel intraluminal impedance pHmetry were performed in nine chronically instrumented newborn lambs to study gastroesophageal refluxes, esophageal insufflations, states of alertness, laryngeal closure and respiration. Recordings were repeated without sedation in control condition, nPSV (15/4 cmH2O) and nNAVA (~ 15/4 cmH2O). The number of gastroesophageal refluxes recorded over six hours, expressed as median (interquartile range), decreased during both nPSV (1 (0, 3)) and nNAVA [1 (0, 3)] compared to control condition (5 (3, 10)), (p < 0.05). Meanwhile, the esophageal insufflation index did not differ between nPSV (40 (11, 61) h-1) and nNAVA (10 (9, 56) h-1) (p = 0.8). In conclusion, nPSV and nNAVA similarly inhibit gastroesophageal refluxes in healthy newborn lambs at pressures that do not lead to gastric distension. In addition, the occurrence of esophageal insufflations is not significantly different between nPSV and nNAVA. The strong inhibitory effect of nIPPV on gastroesophageal refluxes appears identical to that reported with nasal continuous positive airway pressure.

Presentation and endoscopic management of sigmoid volvulus in children.

UNLABELLED: The aim of the present study was to evaluate clinical presentation and management of sigmoid volvulus in children, focusing on endoscopic reduction. In this retrospective multicenter study, we reviewed the charts of 13 patients with sigmoid volvulus. We recorded clinical symptoms, diagnostic methods, endoscopic or surgical therapy, and outcome. The children (seven girls, six boys) had a median age of 12.8 years (range, 15 months to 17 years) at initial presentation. Eight patients had associated diseases (e.g., chronic constipation, mental retardation, or myopathy). The initial symptoms were abdominal pain (13/13), abdominal distension (11/13), and vomiting (7/13), which were associated with abdominal tenderness in all patients. Abdominal X-ray showed dilated sigmoid loops and air-fluid levels in all patients. Endoscopic reduction by exsufflation was successful without any complications in 12 patients, whereas the youngest patient underwent a first-line sigmoidectomy. Recurrence occurred in 7/12 patients after endoscopic exsufflation. Finally, 11 patients underwent a sigmoidectomy. CONCLUSION: Although rare in children, sigmoid volvulus should be advocated when abdominal pain is associated with dilated sigmoid loops. Sigmoidoscopic exsufflation can be considered as the first-line management in the absence of perforation. However, sigmoidectomy is often required for prevention of recurrence. WHAT IS KNOWN: • Sigmoid volvulus is uncommon in childhood. • Diagnosis is often missed or delayed. What is New: • This is the first pediatric series showing that endoscopic exsufflation is an efficient and safe treatment option. • Elective sigmoid resection with primary anastomosis is often required to prevent recurrence.