Nirsevimab and Hospitalization for RSV Bronchiolitis.

BACKGROUND: Respiratory syncytial virus (RSV) is the leading cause of bronchiolitis, resulting in 3 million hospitalizations each year worldwide. Nirsevimab is a monoclonal antibody against RSV that has an extended half-life. Its postlicensure real-world effectiveness against RSV-associated bronchiolitis is unclear. METHODS: We conducted a prospective, multicenter, matched case-control study to analyze the effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis in infants younger than 12 months of age. Case patients were infants younger than 12 months of age who were hospitalized for RSV-associated bronchiolitis between October 15 and December 10, 2023. Control patients were infants with clinical visits to the same hospitals for conditions unrelated to RSV infection. Case patients were matched to control patients in a 2:1 ratio on the basis of age, date of hospital visit, and study center. We calculated the effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis (primary outcome) by means of a multivariate conditional logistic-regression model with adjustment for confounders. Several sensitivity analyses were performed. RESULTS: The study included 1035 infants, of whom 690 were case patients (median age, 3.1 months; interquartile range, 1.8 to 5.3) and 345 were matched control patients (median age, 3.4 months; interquartile range, 1.6 to 5.6). Overall, 60 case patients (8.7%) and 97 control patients (28.1%) had received nirsevimab previously. The estimated adjusted effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis was 83.0% (95% confidence interval [CI], 73.4 to 89.2). Sensitivity analyses gave results similar to those of the primary analysis. The effectiveness of nirsevimab therapy against RSV-associated bronchiolitis resulting in critical care was 69.6% (95% CI, 42.9 to 83.8) (27 of 193 case patients [14.0%] vs. 47 of 146 matched control patients [32.2%]) and against RSV-associated bronchiolitis resulting in ventilatory support was 67.2% (95% CI, 38.6 to 82.5) (27 of 189 case patients [14.3%] vs. 46 of 151 matched control patients [30.5%]). CONCLUSIONS: In a real-world setting, nirsevimab therapy was effective in reducing the risk of hospitalized RSV-associated bronchiolitis. (Funded by the National Agency for AIDS Research-Emerging Infectious Disease and others; ENVIE ClinicalTrials.gov number, NCT06030505.).

Mortality and neurodevelopmental outcomes at 2 years' corrected age of very preterm infants with necrotising enterocolitis or spontaneous intestinal perforation: The EPIPAGE-2 cohort study.

PURPOSE: The primary objective was to evaluate the impact of necrotising enterocolitis (NEC) and spontaneous intestinal perforation (SIP) on mortality and neurodevelopmental outcomes at 2 years' corrected age (CA) in infants born before 32 weeks' gestation (WG). METHODS: We studied neurodevelopment at 2 years' CA of infants with NEC or SIP who were born before 32 WG from the EPIPAGE-2 cohort study. The primary outcome was death or the presence of moderate-to-severe motor or sensory disability defined by moderate-to-severe cerebral palsy or hearing or visual disability. The secondary outcome was developmental delay defined by a score < 2 SDs below the mean for any of the five domains of the Ages and Stages Questionnaire. RESULTS: At 2 years' CA, 46% of infants with SIP, 34% of infants with NEC, and 14% of control infants died or had a moderate-to-severe sensorimotor disability (p < 0.01). This difference was mainly due to an increase in in-hospital mortality in the infants with SIP or NEC. Developmental delay at 2 years' CA was more frequent for infants with SIP than controls (70.8% vs 44.0%, p = 0.02) but was similar for infants with NEC and controls (49.3% vs 44.0%, p = 0.5). On multivariate analysis, the likelihood of developmental delay was associated with SIP (adjusted odds ratio = 3.0, 95% CI 1.0-9.1) but not NEC as compared with controls. CONCLUSION: NEC and SIP significantly increased the risk of death or sensorimotor disability at 2 years' CA. SIP was also associated with risk of developmental delay at 2 years' CA.

An educational programme in neonatal intensive care units (SEPREVEN): a stepped-wedge, cluster-randomised controlled trial.

BACKGROUND: Patients in neonatal intensive care units (NICUs) are at high risk of adverse events. The effects of medical and paramedical education programmes to reduce these have not yet been assessed. METHODS: In this multicentre, stepped-wedge, cluster-randomised controlled trial done in France, we randomly assigned 12 NICUs to three clusters of four units. Eligible neonates were inpatients in a participating unit for at least 2 days, with a postmenstrual age of 42 weeks or less on admission. Each cluster followed a 4-month multifaceted programme including education about root-cause analysis and care bundles. The primary outcome was the rate of adverse events per 1000 patient-days, measured with a retrospective trigger-tool based chart review masked to allocation of randomly selected files. Analyses used mixed-effects Poisson modelling that adjusted for time. This trial is registered with ClinicalTrials.gov, NCT02598609. FINDINGS: Between Nov 23, 2015, and Nov 2, 2017, event rates were analysed for 3454 patients of these 12 NICUs for 65 830 patient-days. The event rate per 1000 patient-days reduced significantly from the control to the intervention period (33·9 vs 22·6; incidence rate ratio 0·67; 95% CI 0·50-0·88; p=0·0048). INTERPRETATION: A multiprofessional safety-promoting programme in NICUs reduced the rate of adverse events and severe and preventable adverse events in highly vulnerable patients. This programme could significantly improve care offered to critically ill neonates. FUNDING: Solidarity and Health Ministry, France.

Survival and Long-Term Outcomes of Children Who Survived after End-of-Life Decisions in a Neonatal Intensive Care Unit.

OBJECTIVE: To investigate long-term outcomes of infants who survive despite life-and-death discussions with families and a decision to withdraw or withhold life-sustaining interventions (WWLST) in one neonatal intensive care unit. STUDY DESIGN: Medical records for neonatal intensive care unit admissions from 2012 to 2017 were reviewed for presence of WWLST discussions or decisions, as well as the 2-year outcome of all children who survived. WWLST discussions were prospectively recorded in a specific book; follow-up to age 2 years was determined by retrospective chart review. RESULTS: WWLST discussions occurred for 266 of 5251 infants (5%): 151 (57%) were born at term and 115 (43%) were born preterm. Among these discussions, 164 led to a WWLST decision (62%) and 130 were followed by the infant's death (79%). Of the 34 children (21%) surviving to discharge after WWLST decisions, 10 (29%) died before 2 years of age and 11 (32%) required frequent medical follow-up. Major functional limitations were common among survivors, but 8 were classified as functionally normal or with mild-to-moderate functional limitations. CONCLUSIONS: When a WWLST decision was made in our cohort, 21% of the infants survived to discharge. By 2 years of age, the majority of these infants had died or had major functional limitations. This highlights the uncertainty of WWLST decisions during neonatal intensive care and the importance of ensuring that parents are informed of all possibilities. Additional studies including longer-term follow-up and ascertaining the family's views will be important.

Renal vein thrombosis in neonates: a case series of diagnosis, treatment and childhood kidney function follow-up.

BACKGROUND: Neonatal renal vein thrombosis (NRVT) is a rare condition with little data available. METHODS: We retrospectively analyzed newborns diagnosed with NRVT admitted to 3 pediatric nephrology units in Paris from 2005 to 2020. RESULTS: Twenty-seven patients were analyzed (male = 59%). The median age at diagnosis was 2.5 days (1 - 4.5). Diagnosis was suspected based on at least one of the three cardinal signs of renal vein thrombosis in 93%: flank mass (67%), hematuria (67%) and thrombocytopenia (70%). In all patients, diagnosis was confirmed by ultrasound. All patients had at least one known perinatal risk factor. A prothrombotic risk factor was found in 13 patients (48%). NRVT was unilateral in 70%, involving the left renal vein in 58%. Among 25 treated patients, 19 (76%) received low molecular weight heparin (LMWH) as initial therapy, 2 (8%) received unfractionated heparin and 4 (16%) received fibrinolysis. Median duration of treatment was 8 weeks (4 - 12). Bleeding occurred significantly more often with fibrinolysis than with LMWH/supportive therapy (3 of 4: 75% vs 0 of 4: 0%, p = 0.05). Clot resolution in patients treated with fibrinolysis did not differ significantly from those treated with LMWH/supportive therapy. After a median follow-up of 5.7 years (3 years - 9.9 years), pathological kidney features were observed in 73% of the patients (19 of 26), kidney atrophy in 18 (69%), hypertension in 2 (8%), chronic kidney disease (CKD) in 1 (4%) and proteinuria in 2 (8%). CONCLUSIONS: NRVT remains a challenging condition, which still requires further study because of its associated morbidity. A higher resolution version of the Graphical abstract is available as Supplementary information.

Neurocognitive outcomes at age 5 years after prophylactic hydrocortisone in infants born extremely preterm.

AIM: To assess the 5-year neurocognitive outcomes of children born extremely preterm exposed to prophylactic hydrocortisone to improve survival without bronchopulmonary dysplasia. METHOD: This was a prespecified secondary analysis of the PREMILOC clinical trial (trial registration: EudraCT no. 2007-002041-20, NCT00623740). The primary outcome was full-scale IQ based on the Wechsler Preschool and Primary Scale of Intelligence. RESULTS: Among 109 surviving children recruited at the Robert Debré Children's Hospital, Paris, outcome data were available for 42 out of 56 infants (75%) in the group treated with hydrocortisone and 41 out of 53 (77%) in the placebo group. Mean scores were not significantly different between the two groups on full-scale IQ (hydrocortisone: 91.9 [SD = 13.9], placebo: 86.3 [SD = 15.4]; mean difference = 5.7, 95% confidence interval [CI] = -1.0 to 12.3, p = 0.10); however, working memory and retention ability were significantly better in the group treated with hydrocortisone. In a multivariate logistic regression including potential confounding variables, hydrocortisone treatment was significantly associated with a greater chance to survive at 5 years of age with a full-scale IQ equal to or greater than 90 compared to placebo (adjusted odds ratio = 4.26, 95% CI = 1.47-12.36, p = 0.008). INTERPRETATION: This exploratory analysis provides reassuring data regarding the long-term neurodevelopmental safety of prophylactic hydrocortisone in infants born extremely preterm.

Immature brain structures were associated with poorer eye movement performance at 8 years of age in preterm born children.

AIM: Eye movements have rarely been explored in preterm born children. The aim of this study was to compare horizontal eye movements in children born preterm and full term when they reached 8 years of age. METHODS: Eye movements were recorded in 24 preterm born children (18 boys) and 26 matched controls (19 boys), recruited by a French hospital, using an eye tracker. This identified different types of visually guided saccades, namely step, gap, overlap and antisaccades and pursuit eye movements. The saccades task measured the latency and the percentage of anticipatory and express saccades and errors. The pursuit task measured the gain and percentage of intrusive saccades. RESULTS: This study confirmed that children born at 24-28 weeks of gestation demonstrated a global deficit in inhibitory processes compared to children born full term. The saccades were less precise in the preterm group, anticipatory and express saccades were elevated and there was a high occurrence of intrusive saccades during pursuit movements. CONCLUSION: These findings suggest that preterm born children have immature brain structures, particularly the parietal and frontal cortexes that are responsible for both saccade and pursuit performance. These could have been the cause of the abnormal inhibitory control measured in this study.

Intraoperative cerebral oxygen saturation and neurological outcomes following surgical management of necrotizing enterocolitis: Predictive factors of neurological complications following neonatal necrotizing enterocolitis: Predictive factors of neurological complications following neonatal necrotizing enterocolitis.

BACKGROUND: The goal of the present study was to investigate intraoperative factors associated with major neurological complications at 1 year following surgery for necrotizing enterocolitis. MATERIAL AND METHODS: The study consisted of a retrospective review of medical charts of patients operated for over one calendar year in one institution. Data collected included demographic data, cardiac resuscitation at birth, Bell classification, antibiotics usage, time of day of surgery, surgical technique, surgical duration, type of ventilation, intraoperative vasoactive agents, and albumin use, nadir cerebral saturation, the decrease in cerebral saturation from baseline, the time period when cerebral saturation was at least 20% below baseline, and the mean arterial pressure at nadir cerebral saturation. Reported follow-up complications were assessed during formal neonatologist consultation and additional imaging exploration as needed. Analyses included descriptive statistics, and univariable and multivariable statistics. RESULTS: The study included 32 patients with no prior clinical neurological complications, of which 25 had normal cerebral imaging. Severe neurological complications occurred in nine patients at 1 year: Intraventricular hemorrhage (N = 2) and Periventricular leukomalacia (N = 7). However, preoperative cerebral imaging was lacking in seven patients. Consequently, the observed neurological complications at 1 year might be present before the surgery. Multivariable analysis found the decrease in cerebral saturation ≥36% from baseline as the only factor associated with the occurrence of those complications. CONCLUSION: Intraoperative decrease of cerebral oxygen saturation below ≥36% from baseline is associated with severe neurological complications in neonates undergoing surgery for necrotizing enterocolitis.

Association between Baseline Cortisol Serum Concentrations and the Effect of Prophylactic Hydrocortisone in Extremely Preterm Infants.

OBJECTIVE: To define nomograms of serum cortisol values before 24 hours of postnatal life for extremely preterm infants and determine whether baseline cortisol values affect the benefit/risk ratio of prophylactic hydrocortisone to improve survival without bronchopulmonary dysplasia (BPD). STUDY DESIGN: We performed a predefined secondary analysis of the multicenter randomized controlled PREMILOC trial that included inborn infants delivered before 28 weeks of gestation. Nomograms of baseline serum cortisol values measured in 325 enrolled patients were determined for male and female neonates and correlated to perinatal events. BPD-free survival and severe adverse events were analyzed in placebo and hydrocortisone groups according to the cortisol z score in multivariate logistic regression models. RESULTS: Increased cortisol levels measured before 24 hours following birth were associated with a significantly higher chance of BPD-free survival only in placebo-treated infants (aOR [95% CI] 1.57 [1.08-2.27], P = .02) based on sex-specific nomograms for baseline cortisol levels. The cortisol z score for infants treated with prophylactic hydrocortisone predicted a risk of high-grade intraventricular hemorrhage (aOR [95% CI] 1.82 [1.06-3.15], P = .03) and spontaneous intestinal perforation (aOR [95% CI] 4.81 [1.34-17.22], P = .02). CONCLUSIONS: We found no predictive value of baseline cortisol levels for BPD-free survival in infants born extremely preterm treated with hydrocortisone. However, high cortisol levels early after birth were associated with a greater risk of severe intraventricular hemorrhage and spontaneous intestinal perforation in infants treated with hydrocortisone and, therefore, a lower benefit/risk ratio for the treatment. TRIAL REGISTRATION: EudraCT 2007-002041-20, ClinicalTrial.gov: NCT00623740.

Population pharmacokinetic meta-analysis of individual data to design the first randomized efficacy trial of vancomycin in neonates and young infants.

OBJECTIVES: In the absence of consensus, the present meta-analysis was performed to determine an optimal dosing regimen of vancomycin for neonates. METHODS: A 'meta-model' with 4894 concentrations from 1631 neonates was built using NONMEM, and Monte Carlo simulations were performed to design an optimal intermittent infusion, aiming to reach a target AUC0-24 of 400 mg·h/L at steady-state in at least 80% of neonates. RESULTS: A two-compartment model best fitted the data. Current weight, postmenstrual age (PMA) and serum creatinine were the significant covariates for CL. After model validation, simulations showed that a loading dose (25 mg/kg) and a maintenance dose (15 mg/kg q12h if <35 weeks PMA and 15 mg/kg q8h if ≥35 weeks PMA) achieved the AUC0-24 target earlier than a standard 'Blue Book' dosage regimen in >89% of the treated patients. CONCLUSIONS: The results of a population meta-analysis of vancomycin data have been used to develop a new dosing regimen for neonatal use and to assist in the design of the model-based, multinational European trial, NeoVanc.

Cord blood procalcitonin level and early-onset sepsis in extremely preterm infants.

Early-onset neonatal sepsis (EOS) is observed in 1.7% of extremely preterm infants, with high morbidity and mortality rate. Cord blood procalcitonin (PCT) is a sensitive marker of EOS in full-term newborns, but it has been rarely studied in premature infants. The diagnostic value of cord blood PCT by immunofluorescence has been assessed as an early marker of EOS in a prospective cohort of extremely preterm infants, with a threshold at 0.5 µg/L. EOS was defined by a positive bacterial culture or by the association of postnatal biological/clinical signs of EOS and antibiotic treatment for more than 72 h. Correlation between PCT serum concentrations and postnatal morbidities was also analyzed. Among a total of 186 infants, 45 (24%) were classified as EOS. Blood PCT concentration was ≤ 0.5 µg/L in 114 infants, including 11 EOS (9.6%) and PCT was > 0.5 µg/L in 72 babies including 34 EOS (47.2%). PCT concentration > 0.5 µg/L was associated with higher risk of EOS (OR 2.18; CI95% 1.58-3.02; p < 0.0001). The receiver operating characteristic curve determined a cutoff of 0.7 µg/L as the best compromise, with an area under the curve of 0.75 (sensitivity 69%, specificity 70%). In multivariate analysis, clinical chorioamnionitis was associated with PCT concentration > 0.5 µg/L (OR 2.58; CI95% 1.35-4.94; p = 0.004). Cord blood PCT is a marker significantly associated with EOS in extremely preterm infants, but its sensitivity remains low. Its added value in combination with other early marker of EOS needs to be further investigated in this high-risk population.

Melatonin Levels in Preterm and Term Infants and Their Mothers.

The prevention of perinatal brain damage following preterm birth remains a public health priority. Melatonin has been shown to be a promising neuroprotectant in neonatal preclinical models of brain damage, but few studies have investigated melatonin secretion in newborns. We hypothesized that melatonin circulating levels would be lower in preterm compared to term infants. We conducted a prospective, longitudinal, multicenter study to assess melatonin, and 6-sulfatoxy-melatonin (aMT6s) concentrations, measured by radioimmunoassay. Among 209 neonates recruited, 110 were born before 34 gestational weeks (GW) and 99 born after 34 GW. Plasma melatonin concentrations, measured at birth and on Day 3 were below detectable levels (≤7 pg/mL) in 78% and 81%, respectively, of infants born before 34 GW compared to 57% and 34%, respectively, of infants born after 34 GW. The distribution of plasma melatonin concentrations was found to be correlated with gestational age at both time-points (p < 0.001). Median urine aMT6s concentrations were significantly lower in infants born before 34 GW, both on Day 1 (230 ng/L vs. 533 ng/L, p < 0.0001) and on Day 3 (197 ng/L vs. 359 ng/L, p < 0.0001). In conclusion, melatonin secretion appears very low in preterm infants, providing the rationale for testing supplemental melatonin as a neuroprotectant in clinical trials.

Developmental pharmacogenetics of CYP2C19 in neonates and young infants: omeprazole as a probe drug.

AIMS: Although substantial progress has been made in understanding of ontogeny of drug metabolism, there is still a gap of knowledge in developmental pharmacogenetics in neonates. We hypothesized that both age and pharmacogenetics might explain the developmental pattern of CYP2C19. We conducted a population pharmacokinetic-pharmacogenetic study to quantify the developmental pharmacogenetics of CYP2C19 in neonates and young infants using omeprazole as a probe drug. METHODS: Pharmacokinetic samples were collected from 51 Caucasian neonates and young infants, who were receiving omeprazole treatment. Population pharmacokinetic-pharmacogenetic analysis of omeprazole and its metabolites was performed using NONMEM. RESULTS: Data fitted a one-compartment parent and metabolite model with first-order absorption and elimination. CYP2C19 and CYP3A4 are predominantly involved in the metabolism of omeprazole despite their relatively low activities compared to adults. The clearance of omeprazole converted to 5-hydroxy-omeprazole (CLOMZ-M1 ) increases with postnatal age. In CYP2C19 poor and intermediate metabolizers, model-predicted CLOMZ-M1 are 12.5% (5-95% percentile: 3-14.9%) and 44.9% (5-95% percentile: 29.9-72.6%) of the value in extensive/ultrarapid metabolizer, respectively. Model-predicted absorption rate constant of omeprazole is 6.93 (5-95% percentile: 3.01-14.61) times higher in ABCB1 homozygous mutant patients, 1.86 (5-95% percentile: 0.86-3.47) times higher in ABCB1 heterozygous patients than that in ABCB1 homozygous wild-type patients. CONCLUSIONS: Developmental pharmacogenetics of CYP2C19 was quantitatively described in neonates and young infants using omeprazole as a probe drug. Our findings emphasize the importance of semiphysiological developmental pharmacokinetic modelling approach when evaluating developmental pharmacogenetics of drugs with multiple routes of biotransformation.

Association Between Early Low-Dose Hydrocortisone Therapy in Extremely Preterm Neonates and Neurodevelopmental Outcomes at 2 Years of Age.

Importance: Dexamethasone to prevent bronchopulmonary dysplasia in very preterm neonates was associated with adverse neurodevelopmental events. Early low-dose hydrocortisone treatment has been reported to improve survival without bronchopulmonary dysplasia but its safety with regard to neurodevelopment remains to be assessed. Objective: To assess whether early hydrocortisone therapy in extremely preterm infants is associated with neurodevelopmental impairment at 2 years of age. Design, Setting, and Participants: An exploratory secondary analysis of the PREMILOC (Early Low-Dose Hydrocortisone to Improve Survival without Bronchopulmonary Dysplasia in Extremely Preterm Infants) randomized clinical trial conducted between 2008 and 2014 in 21 French neonatal intensive care units. Randomization was stratified by gestational age groups. Neurodevelopmental assessments were completed from 2010 to 2016. Interventions: After birth, patients were randomly assigned to receive placebo or hydrocortisone (0.5 mg/kg twice per day for 7 days, followed by 0.5 mg/kg per day for 3 days). Main Outcomes and Measures: The prespecified exploratory secondary outcome of neurodevelopmental impairment was based on a standardized neurological examination and the revised Brunet-Lézine scale (global developmental quotient score and subscores; mean norm, 100 [SD, 15]). The minimal clinically important difference on the global developmental quotient was 5 points. Results: Of 1072 neonates screened, 523 were assigned to hydrocortisone (n = 256) or placebo (n = 267) and 406 survived to 2 years of age. A total of 379 patients (93%; 46% female) were evaluated (194 in the hydrocortisone group and 185 in the placebo group) at a median corrected age of 22 months (interquartile range, 21-23 months). The distribution of patients without neurodevelopmental impairment (73% in the hydrocortisone group vs 70% in the placebo group), with mild neurodevelopmental impairment (20% in the hydrocortisone group vs 18% in the placebo group), or with moderate to severe neurodevelopmental impairment (7% in the hydrocortisone group vs 11% in the placebo group) was not statistically significantly different between groups (P = .33). The mean global developmental quotient score was not statistically significantly different between groups (91.7 in the hydrocortisone group vs 91.4 in the placebo group; between-group difference, 0.3 [95% CI, -2.7 to 3.4]; P = .83). The incidence of cerebral palsy or other major neurological impairments was not significantly different between groups. Conclusions and Relevance: In this exploratory analysis of secondary outcomes of a randomized clinical trial of extremely preterm infants, early low-dose hydrocortisone was not associated with a statistically significant difference in neurodevelopment at 2 years of age. Further randomized studies are needed to provide definitive assessment of the neurodevelopmental safety of hydrocortisone in extremely preterm infants. Trial Registration: clinicaltrials.gov Identifier: NCT00623740.

A Population and Developmental Pharmacokinetic Analysis To Evaluate and Optimize Cefotaxime Dosing Regimen in Neonates and Young Infants.

Cefotaxime is one of the most frequently prescribed antibiotics for the treatment of Gram-negative bacterial sepsis in neonates. However, the dosing regimens routinely used in clinical practice vary considerably. The objective of the present study was to conduct a population pharmacokinetic study of cefotaxime in neonates and young infants in order to evaluate and optimize the dosing regimen. An opportunistic sampling strategy combined with population pharmacokinetic analysis using NONMEM software was performed. Cefotaxime concentrations were measured by high-performance liquid chromatography-tandem mass spectrometry. Developmental pharmacokinetics-pharmacodynamics, the microbiological pathogens, and safety aspects were taken into account to optimize the dose. The pharmacokinetic data from 100 neonates (gestational age [GA] range, 23 to 42 weeks) were modeled with an allometric two-compartment model with first-order elimination. The median values for clearance and the volume of distribution at steady state were 0.12 liter/h/kg of body weight and 0.64 liter/kg, respectively. The covariate analysis showed that current weight, GA, and postnatal age (PNA) had significant impacts on cefotaxime pharmacokinetics. Monte Carlo simulations demonstrated that the current dose recommendations underdosed older newborns. A model-based dosing regimen of 50 mg/kg twice a day to four times a day, according to GA and PNA, was established. The associated risk of overdose for the proposed dosing regimen was 0.01%. We determined the population pharmacokinetics of cefotaxime and established a model-based dosing regimen to optimize treatment for neonates and young infants.

Clinical Utility and Safety of a Model-Based Patient-Tailored Dose of Vancomycin in Neonates.

Pharmacokinetic modeling has often been applied to evaluate vancomycin pharmacokinetics in neonates. However, clinical application of the model-based personalized vancomycin therapy is still limited. The objective of the present study was to evaluate the clinical utility and safety of a model-based patient-tailored dose of vancomycin in neonates. A model-based vancomycin dosing calculator, developed from a population pharmacokinetic study, has been integrated into the routine clinical care in 3 neonatal intensive care units (Robert Debré, Cochin Port Royal, and Clocheville hospitals) between 2012 and 2014. The target attainment rate, defined as the percentage of patients with a first therapeutic drug monitoring serum vancomycin concentration achieving the target window of 15 to 25 mg/liter, was selected as an endpoint for evaluating the clinical utility. The safety evaluation was focused on nephrotoxicity. The clinical application of the model-based patient-tailored dose of vancomycin has been demonstrated in 190 neonates. The mean (standard deviation) gestational and postnatal ages of the study population were 31.1 (4.9) weeks and 16.7 (21.7) days, respectively. The target attainment rate increased from 41% to 72% without any case of vancomycin-related nephrotoxicity. This proof-of-concept study provides evidence for integrating model-based antimicrobial therapy in neonatal routine care.

Escherichia Coli Meningitis Features in 325 Children From 2001 to 2013 in France.

BACKGROUND: We aimed to describe features of Escherichia coli meningitis in a large population of children and the molecular characteristics of the involved strains to determine factors associated with severe disease or death. METHODS: Between 2001 and 2013, a prospective national survey collected data for 325 children hospitalized with E. coli meningitis. The national reference center genetically characterized 141 isolates. RESULTS: Among the 325 cases, 65.2% were term, 22.4% late preterm, and 12.5% very/extremely preterm infants. Escherichia coli meningitis was 7-fold more frequent in preterm than term infants. Median age at diagnosis was 14 days; 71.1% of infants were neonates, with 2 peaks of infection at age 0-3 days (mostly preterm neonates) and 11-15 days (mostly term neonates); 8.9% were >89 days old. In total, 51.1% patients were considered to have severe disease, and 9.2% died. B2.1 phylogenetic subgroup (56%) and O1 serogroup (27.7%) were the most frequently identified. On multivariate analysis, death was associated with preterm birth (odds ratio [OR], 3.3 [95% confidence interval {CI}, 1.3-8.4], P = .015 for late preterm infants; OR, 7.3 [95% CI, 2.7-20.9], P < .001 for very/extremely preterm infants) and cerebrospinal fluid (CSF) to blood glucose ratio <0.10 (OR, 15.3 [95% CI, 1.8-128.3], P = .012). Death was associated with uncommon O serogroup strains (P = .014) and severe disease with O7 serogroup (P = .034) and PapGII adhesin (OR, 2.3 [95% CI, 1.2-4.5], P = .015). CONCLUSIONS: In this large study of 325 cases of E. coli meningitis, risk factors of severe disease or death were preterm birth, severe hypoglycorrhachia, CSF/blood glucose ratio <0.10, and molecular characteristics of strains, which should help optimize therapeutic management.

Is melatonin ready to be used in preterm infants as a neuroprotectant?

The prevention of neurological disabilities following preterm birth remains a major public health challenge and efforts are still needed to test the neuroprotective properties of candidate molecules. Melatonin serves as a neuroprotectant in adult models of cerebral ischemia through its potent antioxidant and anti-inflammatory effects. An increasing number of preclinical studies have consistently demonstrated that melatonin protects the damaged developing brain by preventing abnormal myelination and an inflammatory glial reaction, a major cause of white matter injury. The main questions asked in this review are whether preclinical data on the neuroprotective properties of melatonin are sufficient to translate this concept into the clinical setting, and whether melatonin can reduce white matter damage in preterm infants. This review provides support for our view that melatonin is now ready to be tested in human preterm neonates, and discusses ongoing and planned clinical trials.

Quantification of brain-wide vascular resistivity via ultrafast Doppler in human neonates helps early detection of white matter injury.

Preterm birth is associated with cerebrovascular development disruption and can induce white matter injuries (WMI). Transfontanellar ultrasound Doppler is the most widely used clinical imaging technique to monitor neonatal cerebral vascularisation and haemodynamics based on vascular indexes such as the resistivity index (RI); however, it has poor predictive value for brain damage. Indeed, these RI measurements are currently limited to large vessels, leading to a very limited probing of the brain's vascularisation, which may hinder prognosis. Here we show that ultrafast Doppler imaging (UfD) enables simultaneous quantification, in the whole field of view, of the local RI and vessel diameter, even in small vessels. Combining both pieces of information, we defined two new comprehensive resistivity parameters of the vascular trees. First, we showed that our technique is more sensitive in the early characterisation of the RI modifications between term and preterm neonates and for the first time we could show that the RI depends both on the vessel diameter and vascular territory. We then showed that our parameters can be used for early prediction of WMI. Our results demonstrate the potential of UfD to provide new biomarkers and pave the way for continuous monitoring of neonatal brain resistivity.

Association between Portal Vein Thrombosis after Umbilical Vein Catheterization and Neonatal Asphyxia.

INTRODUCTION: Neonatal portal vein thrombosis (PVT) is frequently related to umbilical venous catheterization (UVC), but risk factors remain unclear. This study aims to analyze the variables associated to PVT in near- to full-term newborns with UVC, with a focus on newborns exposed to controlled therapeutic hypothermia (CTH) for hypoxic ischemic encephalopathy (HIE). METHODS: This is retrospective cohort study of infants delivered at or after 36 weeks and with a birthweight over 1,500 g. All infants were assessed for UVC location and PVT using ultrasonography performed between day 5 and day 10 after catheterization. RESULTS: Among 213 eligible patients, PVT was diagnosed in 57 (27%); among them, 54 (95%) were localized in the left portal vein branch. With all significant factors in univariate analysis considered, higher gestational age at birth (adjusted OR 1.35; 95% CI: 1.12-1.64, p = 0.002) and duration of UVC placement (adjusted OR 1.36; 95% CI: 1.11-1.67, p = 0.004) were the main risk factors of PVT. Among 87 infants who were cooled for HIE, 31 (36%) had PVT compared to 26 (21%) in infants without CTH. Using a multivariate model including variables linked to treatment procedures only, an increased PVT incidence was statistically associated with UVC duration (adjusted OR 1.33; 95% CI: 1.08; 1.63, p = 0.01) and CTH (adjusted OR 1.94; 95% CI: 1.04-3.65, p = 0.04). CONCLUSION: Left PVT was frequently observed in near- to full-term neonates with UVC. Among factors linked to treatment procedures, both duration of UVC and CTH exposure for HIE were found to be independent risk factors of PVT.