Evaluation of furosemide regimens in neonates treated with extracorporeal membrane oxygenation

INTRODUCTION: Loop diuretics are the most frequently used diuretics in patients treated with extracorporeal membrane oxygenation (ECMO). In patients after cardiopulmonary bypass (CPB) surgery, the use of continuous furosemide infusion is increasingly documented. Because ECMO and CPB are 'comparable' procedures, continuous furosemide infusion is used in newborns on ECMO. We report on the use of continuous intravenous furosemide in neonates treated with ECMO. METHODS: This was a retrospective observational study in neonates treated with continuous intravenous furosemide during ECMO. RESULTS: Thirty-one patients were included in the study. A median of 25 (9–149) hours after the start of ECMO, continuous furosemide therapy was started at a median rate of 0.08 (0.02–0.17) mg/kg per hour. The continuous furosemide dose was not changed in the individual patient. Seven patients received a furosemide bolus prior to, and five patients received additional loop diuretics during, the continuous infusion. Urine production before continuous furosemide therapy was not significantly different between patients who received a furosemide bolus prior to the infusion and those who did not receive this bolus (P = 0.2879). Although a positive effect of the 'loading' bolus was observed in urine output in the first 24 hours, there was no statistically significant difference in urine output (P = 0.0961) or in time (P = 0.1976) to reach a urine output of 6 ml/kg per hour between patients. After 24 hours, urine production remained a median of 6.2 ml/kg per hour irrespective of furosemide boluses. The forced diuresis was well tolerated as illustrated by stable haemodynamic parameters and a decrease in ECMO flow and vasopressor score over the observation period. CONCLUSION: This is the first report on continuous intravenous furosemide therapy in newborns treated with ECMO. The furosemide regimens used in this study varied widely in continuous and intermittent doses. However, all regimens achieved adequate urine output. An advantage of continuous, over intermittent, intravenous furosemide could not be documented. Furosemide dosing regimens should be developed for neonates treated with ECMO. In addition, therapeutic drug-monitoring studies are required to prevent furosemide toxicity because so far no data are available on serum furosemide levels in neonates treated with ECMO

Mycophenolate mofetil versus cyclosporine for remission maintenance in nephrotic syndrome

We performed a multi-centre randomized controlled trial to compare the efficacy of mycophenolate mofetil (MMF) to that of cyclosporine A (CsA) in treating children with frequently relapsing nephrotic syndrome and biopsy-proven minimal change disease. Of the 31 randomized initially selected patients, seven were excluded. The remaining 24 children received either MMF 1200 mg/m2per day (n = 12) or CsA 4-5 mg/kg per day (n = 12) during a 12-month period. Of the 12 patients in the MMF group, two discontinued the study medication. Evaluation of the changes from the baseline glomerular filtration rate showed an overall significant difference in favour of MMF over the treatment period (p = 0.03). Seven of the 12 patients in the MMF group and 11 of the 12 patients in the CsA group remained in complete remission during the entire study period. Relapse rate in the MMF group was 0.83/year compared to 0.08/year in the CsA group (p = 0.08). None of the patients reported diarrhea. Pharmacokinetic profiles of mycophenolic acid were performed in seven patients. The patient with the lowest area under the curve had three relapses within 6 months. In children with frequently relapsing minimal change nephrotic syndrome, MMF has a favourable side effect profile compared to CsA; however, there is a tendency towards a higher relapse risk in patients treated with MMF

Renal Phenotype in Lowe Syndrome: A Selective Proximal Tubular Dysfunction

Background and objectives: Lowe syndrome is defined by congenital cataracts, mental retardation, and proximal tubulopathy and is due to mutations in OCRL. Recently, mutations in OCRL were found to underlie some patients with Dent disease, characterized by low molecular weight proteinuria, hypercalciuria, and nephrocalcinosis. This phenotypic heterogeneity is poorly understood

Is mid-upper arm circumference in Dutch children useful in identifying obesity?

Background Mid-upper arm circumference (MUAC) is suggested as being a valid measure in detecting overweight/obesity in children and adolescents, due to the strong relation with weight. We examined this relation and compared MUAC to body mass index (BMI) according to the International Obesity Task Force (IOTF) in children. Methods Anthropometric data including MUAC were collected in 2009 by trained healthcare professionals in the context of the fifth Dutch Nationwide Growth Study, in a sample of 6167 children (2891 boys and 3276 girls) aged 2-18 years of Dutch origin. We propose MUAC SDS cut-off values for overweight and obesity, and compared MUAC with BMI IOTF in sex-specific and age-specific categories (2-5, 6-11, 12-18 years). Results The area under the curve is used as a measure of diagnostic accuracy; the explained variance (R) is good to excellent (0.88-0.94). Sensitivity ranges from 51.8% to 95.3% and specificity from 71.4% to 93.8%. Across age and gender groups, 65.1% to 89.0% participants are classified by both MUAC and BMI as normal weight, overweight or obese. We constructed three equations to predict weight using MUAC, with small differences between observed and predicted weight with an explained variance ranging from 0.88 to 0.94. Conclusions Compared with BMI, MUAC is a valid measure for detecting overweight and obesity and thus a good alternative for BMI. When weight has to be estimated, it can be accurately predicted using MUAC. Based on our observations, we recommend developing diagrams with international (IOTF) cut-offs for MUAC SDS similar to BMI

Is mid-upper arm circumference in Dutch children useful in identifying obesity?

Background Mid-upper arm circumference (MUAC) is suggested as being a valid measure in detecting overweight/obesity in children and adolescents, due to the strong relation with weight. We examined this relation and compared MUAC to body mass index (BMI) according to the International Obesity Task Force (IOTF) in children. Methods Anthropometric data including MUAC were collected in 2009 by trained healthcare professionals in the context of the fifth Dutch Nationwide Growth Study, in a sample of 6167 children (2891 boys and 3276 girls) aged 2-18 years of Dutch origin. We propose MUAC SDS cut-off values for overweight and obesity, and compared MUAC with BMI IOTF in sex-specific and age-specific categories (2-5, 6-11, 12-18 years). Results The area under the curve is used as a measure of diagnostic accuracy; the explained variance (R) is good to excellent (0.88-0.94). Sensitivity ranges from 51.8% to 95.3% and specificity from 71.4% to 93.8%. Across age and gender groups, 65.1% to 89.0% participants are classified by both MUAC and BMI as normal weight, overweight or obese. We constructed three equations to predict weight using MUAC, with small differences between observed and predicted weight with an explained variance ranging from 0.88 to 0.94. Conclusions Compared with BMI, MUAC is a valid measure for detecting overweight and obesity and thus a good alternative for BMI. When weight has to be estimated, it can be accurately predicted using MUAC. Based on our observations, we recommend developing diagrams with international (IOTF) cut-offs for MUAC SDS similar to BMI

Is mid-upper arm circumference in Dutch children useful in identifying obesity?

Background Mid-upper arm circumference (MUAC) is suggested as being a valid measure in detecting overweight/obesity in children and adolescents, due to the strong relation with weight. We examined this relation and compared MUAC to body mass index (BMI) according to the International Obesity Task Force (IOTF) in children. Methods Anthropometric data including MUAC were collected in 2009 by trained healthcare professionals in the context of the fifth Dutch Nationwide Growth Study, in a sample of 6167 children (2891 boys and 3276 girls) aged 2-18 years of Dutch origin. We propose MUAC SDS cut-off values for overweight and obesity, and compared MUAC with BMI IOTF in sex-specific and age-specific categories (2-5, 6-11, 12-18 years). Results The area under the curve is used as a measure of diagnostic accuracy; the explained variance (R) is good to excellent (0.88-0.94). Sensitivity ranges from 51.8% to 95.3% and specificity from 71.4% to 93.8%. Across age and gender groups, 65.1% to 89.0% participants are classified by both MUAC and BMI as normal weight, overweight or obese. We constructed three equations to predict weight using MUAC, with small differences between observed and predicted weight with an explained variance ranging from 0.88 to 0.94. Conclusions Compared with BMI, MUAC is a valid measure for detecting overweight and obesity and thus a good alternative for BMI. When weight has to be estimated, it can be accurately predicted using MUAC. Based on our observations, we recommend developing diagrams with international (IOTF) cut-offs for MUAC SDS similar to BMI

Population Pharmacokinetics of Prednisolone in Relation to Clinical Outcome in Children With Nephrotic Syndrome

The relapse frequency in children with nephrotic syndrome (NS) is highly variable despite standardized prednisolone treatment regimens. Existing evidence on the relationship between prednisolone pharmacokinetics (PK) and clinical response in children with NS is scarce and limited. The aim of this study was to develop a pediatric popPK model for prednisolone based on our previous model based on healthy adults using salivary measurements in children with NS and to correlate clinical outcome with between-subject variability in prednisolone exposure. The pharmacokinetics of prednisolone in a well-defined, prospective cohort consisting of 104 children with NS while in remission was determined. Pharmacokinetic parameters were analyzed in relation to relapse patterns and side effects. Noninvasive salivary prednisolone measurements were performed using a sparse sampling strategy. A population pharmacokinetic approach was used to derive individual estimates of apparent clearance (CL/F) and apparent volume of distribution (V/F) from the salivary concentration-time curve, followed by calculation of the area under the curve (AUC) of free prednisolone. The individual free serum prednisolone exposure from prednisolone in saliva was derived from the salivary concentration-time curves. Genetic polymorphisms of CYP3A4, CYP3A5, ABCB1, NR1L2, and POR were explored in relation to between-subject variability of CL/F. Moderate interindividual variability was found for CL/F (CV, 44.7%). Unexplained random between-subject variability (eta) of CL/F was lower in patients carrying 1 or 2 ABCB1 3435C>T alleles compared to wild type: median -0.04 (interquartile range, -0.17 to 0.21) and 0.00 (-0.11 to 0.16) versus 0.17 (-0.08 to 0.47), P = 0.046. Exposure to free prednisolone was not associated with frequent relapses or adverse effects. This study provides evidence for the possibility of prednisolone drug monitoring through salivary measurements and this may be of particular usefulness in pediatric patients. However, the observed variability in prednisolone exposure, in the therapeutic dose range studied, is not considered to be a major determinant of clinical outcome in children with N

Role of glucocorticoid metabolism in childhood obesity-associated hypertension

Objective: Childhood obesity is associated with alterations in hypothalamus–pituitary– adrenal axis activity. We tested the hypothesis that multiple alterations in the metabolism of glucocorticoids are required for the development of hypertension in children who become overweight. Methods: Spot urine for targeted gas chromatography-mass spectrometry steroid metabolome analysis was collected from (1) overweight/hypertensive children (n = 38), (2) overweight/non-hypertensive children (n = 83), and (3) non-overweight/non-hypertensive children (n = 56). Results: The mean (± s.d.) age of participants was 10.4 ± 3.4 years, and 53% of them were male. Group 1 and group 2 had higher excretion rates of cortisol and corticosterone metabolites than group 3 (869 (interquartile range: 631–1352) vs 839 (609–1123) vs 608 (439–834) μg/mmol creatinine × m2 body surface area, P group 2 or 3), and CYP3A4 activity (group 1 < group 2 or 3). Discussion: The sequence of events leading to obesity-associated hypertension in children may involve an increase in the production of glucocorticoids, downregulation of 11β-hydroxysteroid dehydrogenase type 1 activity, and upregulation of 5α-reductase activity, along with a decrease in CYP3A4 activity and an increase in bioavailable cortisol