Paediatric research in the times of COVID-19.

The COVID-19 pandemic poses many direct and indirect consequences for children's health and associated research. Direct consequences include participation of children in COVID-19 research trials, pausing other research in children and the potential implications of a global economic downturn on future research funding. Collaborative and networked research together with streamlined research processes and use of remote technology have been central to efforts by clinicians and scientists around the world and have proved essential for reducing COVID-19 morbidity and mortality. IMPACT: Maintain streamlined and efficient approaches to research governance and data sharing to facilitate high-quality collaborative research. Ensure early inclusion of children in trials of therapies for diseases that affect all age groups. Paediatric Research Societies should co-ordinate effective processes to define key research questions and develop multinational clinical trials for diagnostics, therapeutics and preventative strategies for infants, children and young people.

Bifidobacterium breve BBG-001 and intestinal barrier function in preterm babies: Exploratory Studies from the PiPS Trial.

BACKGROUND: Uncertainty remains about the role of probiotics to prevent necrotising enterocolitis (NEC) some of which arises from the variety of probiotic interventions used in different trials, many with no prior evidence of potential efficacy. Mechanistic studies of intestinal barrier function embedded in a large probiotic trial could provide evidence about which properties of probiotics might be important for NEC prevention thus facilitating identification of strains with therapeutic potential. METHODS: Intestinal permeability, stool microbiota, SCFAs and mucosal inflammation were assessed from the second postnatal week in babies enrolled to a randomised controlled trial of B. breve BBG-001 (the PiPS trial). Results were compared by allocation and by stool colonisation with the probiotic. RESULTS: Ninety-four preterm babies were recruited across six nested studies. B. breve BBG-001 content was higher by allocation and colonisation; Enterobacteriaceae and acetic acid levels were higher by colonisation. No measure of intestinal barrier function showed differences. The PiPS trial found no evidence of efficacy to reduce NEC. CONCLUSIONS: That the negative results of the PiPS trial were associated with failure of this probiotic to modify intestinal barrier function supports the possibility that the tests described here have the potential to identify strains to progress to large clinical trials. IMPACT: Uncertainty about the therapeutic role of probiotics to prevent necrotising enterocolitis is in part due to the wide range of bacterial strains with no previous evidence of efficacy used in clinical trials. We hypothesised that mechanistic studies embedded in a probiotic trial would provide evidence about which properties of probiotics might be important for NEC prevention. The finding that the probiotic strain tested, Bifidobacterium breve BBG-001, showed neither effects on intestinal barrier function nor clinical efficacy supports the possibility that these tests have the potential to identify strains to progress to large clinical trials.

Evaluating preterm care across Europe using the eNewborn European Network database.

BACKGROUND: The inefficiency of recording data repeatedly limits the number of studies conducted. Here we illustrate the wider use of data captured as part of the European eNewborn benchmarking programme. METHODS: We extracted data on 39,529 live-births from 22 weeks 0 days to 31 weeks 6 days gestational age (GA) or ≤1500 g birth weight. We explored relationships between delivery room care and Apgar scores on mortality and bronchopulmonary dysplasia (BPD) and calculated the time needed for each country to detect a clinically relevant change in these outcomes following a hypothetical intervention. RESULTS: Early neonatal, neonatal, and in-hospital mortality were 3.90% (95% CI 3.71, 4.09), 6.00% (5.77, 6.24) and 7.57% (7.31, 7.83), respectively. The odds of death were greater with decreasing GA, lower Apgar scores, growth restriction, male sex, multiple birth and no antenatal steroids. Relationships for BPD were similar. The time required for participating countries to achieve 80% power to detect a relevant change in outcomes following a hypothetical intervention in 23-25 weeks' GA infants ranged from 12 years for neonatal mortality and 22 years for BPD compared to 1 year for the whole network. CONCLUSIONS: The eNewborn platform offers opportunity to drive efficiencies in benchmarking, quality control and research.

Bifidobacterium breve BBG-001 in very preterm infants: a randomised controlled phase 3 trial.

BACKGROUND: Probiotics may reduce necrotising enterocolitis and late-onset sepsis after preterm birth. However, there has been concern about the rigour and generalisability of some trials and there is no agreement about whether or not they should be used routinely. We aimed to test the effectiveness of the probiotic Bifidobacterium breve BBG-001 to reduce necrotising enterocolitis, late-onset sepsis, and death in preterm infants. METHODS: In this multicentre, randomised controlled phase 3 study (the PiPS trial), we recruited infants born between 23 and 30 weeks' gestational age within 48 h of birth from 24 hospitals in southeast England. Infants were randomly assigned (1:1) to probiotic or placebo via a minimisation algorithm randomisation programme. The probiotic intervention was B breve BBG-001 suspended in dilute elemental infant formula given enterally in a daily dose of 8·2 to 9·2 log10 CFU; the placebo was dilute infant formula alone. Clinicians and families were masked to allocation. The primary outcomes were necrotising enterocolitis (Bell stage 2 or 3), blood culture positive sepsis more than 72 h after birth; and death before discharge from hospital. All primary analyses were by intention to treat. This trial is registered with ISRCTN, number 05511098 and EudraCT, number 2006-003445-17. FINDINGS: Between July 1, 2010, and July 31, 2013, 1315 infants were recruited; of whom 654 were allocated to probiotic and 661 to placebo. Five infants had consent withdrawn after randomisation, thus 650 were analysed in the probiotic group and 660 in the placebo group. Rates of the primary outcomes did not differ significantly between the probiotic and placebo groups. 61 infants (9%) in the probiotic group had necrotising enterocolitis compared with 66 (10%) in the placebo group (adjusted risk ratio 0·93 (95% CI 0·68-1·27); 73 (11%) infants in the probiotics group had sepsis compared with 77 (12%) in the placebo group (0·97 (0·73-1·29); and 54 (8%) deaths occurred before discharge home in the probiotic group compared with 56 (9%) in the placebo group (0·93 [0·67-1·30]). No probiotic-associated adverse events were reported. INTERPRETATION: There is no evidence of benefit for this intervention in this population; this result does not support the routine use of B breve BBG-001 for prevention of necrotising enterocolitis and late-onset sepis in very preterm infants. FUNDING: UK National Institute for Health Research Health Technology Assessment programme.

ESBL-producing Enterobacteriaceae in 24 neonatal units and associated networks in the south of England: no clustering of ESBL-producing Escherichia coli in units or networks.

OBJECTIVES: The objectives of this study were to characterize ESBL-producing Enterobacteriaceae present in 24 neonatal units (NNUs) in eight networks participating in a multicentre probiotic study and to test the hypothesis that specific strains would cluster within individual units and networks. METHODS: We performed analysis of stool samples for the presence of ESBL-producing Enterobacteriaceae at 2 weeks post-natal age and 36 weeks post-menstrual age. ESBL-producing Enterobacteriaceae were characterized and typed using molecular methods. RESULTS: ESBL-producing Enterobacteriaceae (n = 71) were isolated from 67/1229 (5.5%) infants from whom we received a sample at either sampling time or both sampling times, and from infants in 18 (75%) of the 24 recruiting NNUs. Thirty-three Escherichia coli, 23 Klebsiella spp. and 6 Enterobacter spp. strains were characterized. ESBL-producing E. coli were all distinguishable within individual NNUs by antibiotic resistance genotype, serogroup (O25b), phenotype, phylotype or ST. Ten of the 33 were ST131 and 9 of the 10 ST131 isolates were ciprofloxacin resistant. Seven of the 10 ST131 isolates carried genes encoding CTX-M group 1 enzymes. ST131 isolates were isolated from centres within five of the eight NNU networks. There were clusters of indistinguishable ESBL-producing Klebsiella and Enterobacter isolates associated with specific NNUs. CONCLUSIONS: Strains of E. coli ST131 were distributed across neonatal networks in the south of England. There was no evidence of clustering of clonally related ESBL-producing E. coli strains, by contrast with Klebsiella spp. and Enterobacter spp., which did cluster within units. The possibility that ESBL-producing E. coli strains are spread by vertical transmission requires further investigation.

Investigating increased admissions to neonatal intensive care in England between 1995 and 2006: data linkage study using Hospital Episode Statistics.

BACKGROUND: A 44 % increase was observed in admissions to neonatal intensive care of babies born ≤26 weeks completed gestational age in England between 1995 and 2006. Hospital Episode Statistics (HES) may provide supplementary information to investigate this. The methods and results of a probabilistic data linkage exercise are reported. METHODS: Two data sets were linked for each year (1995 and 2006) using 3 different algorithms (Fellegi and Sunter, Contiero and estimation-maximisation). RESULTS: In 1995, linkage was performed between 668 EPICure and 486,705 HES records; 1,820 linked pairs were identified of which 422 (63.17 %) were confirmed. In 2006, from 2,750 EPICure and 631,401 HES records, 8,913 linked pairs were identified with 1,662 (60.40 %) confirmed as true. Reported births in HES at <26 weeks gestation increased 37.0 % from 867 to 1188. CONCLUSIONS: Results support the EPICure findings that there was an increase in the birth rate for extremely premature babies between 1995 and 2006. There were insufficient data available for detailed investigation. Routine data sources may not be suitable for investigations at the margins of viability.

Impact of obstetric interventions on condition at birth in extremely preterm babies: evidence from a national cohort study.

BACKGROUND: To investigate perinatal decision-making and the use of obstetric interventions, we examined the effects of antenatal steroids, tocolysis, and delivery mode on birth in a good condition (defined as presence of an infant heart rate >100 at five minutes of age) and delivery-room (DR) death in extremely preterm deliveries. METHODS: Prospective cohort of all singleton births in England in 2006 at 22-26 weeks of gestation where the fetus was alive at the start of labour monitoring or decision to perform caesarean section. Odds ratios adjusted for potential confounders (aOR) were calculated using logistic regression. RESULTS: One thousand seven hundred twenty two singleton pregnancies were included. 1231 women received antenatal steroids, 437 tocolysis and 356 delivered by Caesarean section. In babies born vaginally, aOR between a partial course of steroids and improved condition at birth was 1.84, 95% CI: 1.20 to 2.82 and, for a complete course, 1.63, 95% CI: 1.08 to 2.47; for DR death, aORs were 0.34 (0.21 to 0.55) and 0.41 (0.26 to 0.64) for partial and complete courses of steroids. No association was seen for steroid use in babies delivered by Caesarean section. Tocolysis was associated with improved condition at birth (aOR 1.45, 95% CI: 1.05 to 2.0) and lower odds of death (aOR 0.48, 95% CI: 0.32 to 0.73). In women without spontaneous labour, Caesarean delivery at ≤24 and 25 weeks was associated with improved condition at birth ((aORs 12.67 (2.79 to 57.60) and 4.94 (1.44 to 16.90), respectively) and lower odds of DR death (aORs 0.03 (0.01 to 0.21) and 0.13 (0.03 to 0.55)). There were no differences at 26 weeks gestation or in women with spontaneous labour. CONCLUSIONS: Antenatal steroids are strongly associated with improved outcomes in babies born vaginally. Tocolysis was associated with improvements in all analyses. Effects persisted after adjustment for perinatal decision-making. However, associations between delivery mode and birth outcomes may be attributable to case selection.

Changes in the intestinal microbiome of the preterm baby associated with stopping non-invasive pressure support: a prospective cohort study.

BACKGROUND: Intestinal dysbiosis is implicated in the pathogenesis of necrotising enterocolitis and late-onset sepsis in preterm babies. The provision of non-invasive positive pressure ventilation is a common clinical intervention in preterm babies, and may be hypothesised to adversely affect intestinal bacterial growth, through increased aerophagia and induction of a hyperoxic intestinal environment; however this relationship has not been previously well characterised. METHODOLOGY: In this prospectively recruited cohort study, high-throughput 16S rRNA gene sequencing was combined with contemporaneous clinical data collection, to assess within-subject changes in microbiome development around the time of transitioning from non-invasive positive pressure respiratory support to unsupported spontaneous breathing. RESULTS: In a group of 14 preterm infants, bacterial diversity was seen to increase by 0.34 units/week (inverse Simpson index) at the point of transitioning off non-invasive positive pressure respiratory support. Correspondingly, a significant increase in anaerobic genera (Bifidobacteria spp, Veillonella spp), and a non-significant fall in Enterobacteriaceae was also seen at this time. CONCLUSIONS: Provision of non-invasive positive pressure ventilation is associated with suppression of both diversity accrual and obligate anaerobic growth in the preterm intestine. This has clinical implications in view of the widespread use of non-invasive positive pressure ventilation in preterm neonatal care (and wider adult use), and demonstrates the need for potential strategies (eg, probiotic support; reduced aerophagia) to support the development of a healthy gut microbiome during this time.

How frequent is routine use of probiotics in UK neonatal units?

OBJECTIVE: There is a lack of UK guidance regarding routine use of probiotics in preterm infants to prevent necrotising enterocolitis, late-onset sepsis and death. As practices can vary, we aimed to determine the current usage of probiotics within neonatal units in the UK. DESIGN AND SETTING: Using NeoTRIPS, a trainee-led neonatal research network, an online survey was disseminated to neonatal units of all service levels within England, Scotland, Northern Ireland and Wales in 2022. Trainees were requested to complete one survey per unit regarding routine probiotic administration. RESULTS: 161 of 188 (86%) neonatal units responded to the survey. 70 of 161 (44%) respondents routinely give probiotics to preterm infants. 45 of 70 (64%) use the probiotic product Lactobacillus acidophilus NCFM/Bifidobacterium bifidum Bb-06/B. infantis Bi-26 (Labinic™). 57 of 70 (81%) start probiotics in infants ≤32 weeks' gestation. 33 of 70 (47%) had microbiology departments that were aware of the use of probiotics and 64 of 70 (91%) had a guideline available. Commencing enteral feeds was a prerequisite to starting probiotics in 62 of 70 (89%) units. The majority would stop probiotics if enteral feeds were withheld (59 of 70; 84%) or if the infant was being treated for necrotising enterocolitis (69 of 70; 99%). 24 of 91 (26%) units that did not use probiotics at the time of the survey were planning to introduce them within the next 12 months. CONCLUSIONS: More than 40% of all UK neonatal units that responded are now routinely administering probiotics, with variability in the product used. With increased probiotic usage in recent years, there is a need to establish whether this translates to improved clinical outcomes.

Lung function is abnormal in 3-month-old infants with cystic fibrosis diagnosed by newborn screening.

BACKGROUND: Long-term benefits of newborn screening (NBS) for cystic fibrosis (CF) have been established with respect to nutritional status, but effects on pulmonary health remain unclear. HYPOTHESIS: With early diagnosis and commencement of standardised treatment, lung function at ∼3 months of age is normal in NBS infants with CF. METHODS: Lung clearance index (LCI) and functional residual capacity (FRC) using multiple breath washout (MBW), plethysmographic (pleth) FRC and forced expirations from raised lung volumes were measured in 71 infants with CF (participants in the London CF Collaboration) and 54 contemporaneous healthy controls age ∼3 months. RESULTS: Compared with controls, and after adjustment for body size and age, LCI, FRC(MBW) and FRC(pleth) were significantly higher in infants with CF (mean difference (95% CI): 0.5 (0.1 to 0.9), p=0.02; 0.4 (0.1 to 0.7), p=0.02 and 0.9 (0.4 to 1.3), p<0.001, z-scores, respectively), while forced expiratory volume (FEV(0.5)) and flows (FEF(25-75)) were significantly lower (-0.9 (-1.3 to -0.6), p<0.001 and -0.7 (-1.1 to -0.2), p=0.004, z-scores, respectively). 21% (15/70) of infants with CF had an elevated LCI (>1.96 z-scores) and 25% (17/68) an abnormally low FEV(0.5) (below -1.96 z-scores). While only eight infants with CF had abnormalities of LCI and FEV(0.5), using both techniques identified abnormalities in 35% (24/68). Hyperinflation (FRC(pleth) >1.96 z-scores) was identified in 18% (10/56) of infants with CF and was significantly correlated with diminished FEF(25-75) (r=-0.43, p<0.001) but not with LCI or FEV(0.5). CONCLUSION: Despite early diagnosis of CF by NBS and protocol-driven treatment in specialist centres, abnormal lung function, with increased ventilation inhomogeneity and hyperinflation and diminished airway function, is evident in many infants with CF diagnosed through NBS by 3 months of age.

Historical aspects of probiotic use to prevent necrotising enterocolitis in preterm babies.

Over the last few decades, numerous studies have evaluated probiotic use for the prevention of necrotising enterocolitis in preterm babies. Early 'proof of concept' studies evaluating whether probiotics are capable of colonising the preterm gut have translated into multiple observational studies, small and large randomised controlled trials. Some show evidence of benefit while others have produced disappointing results. In this paper, we review the history of probiotic use in preterm babies for NEC prevention in an attempt to explain why uncertainty exists and why this intervention has not been universally adopted into routine neonatal practice.

Colonization and persistence of antibiotic-resistant Enterobacteriaceae strains in infants nursed in two neonatal intensive care units in East London, United Kingdom.

Stool samples were collected from infants nursed in two neonatal intensive care units (NICUs) in East London, United Kingdom. The aim of the study was to determine the incidence of and risk factors for the carriage of multiresistant Enterobacteriaceae strains (MRE; resistant to three or more classes of antibiotic) and the extent of the persistence of resistant strains following discharge. Sixty-two (50%) of 124 infants had acquired MRE by 2 weeks of postnatal age, and 69 (56%) infants had acquired MRE by discharge. The proportions of infants at 2 weeks carrying strains that were resistant to antibiotics were the following: tetracycline, 79%; amoxicillin, 78%; cephalosporins, 31%; trimethoprim, 20%; piperacillin-tazobactam, 11%; chloramphenicol, 9%; and aminoglycoside, 4%. A gestational age of less than 26 weeks was a risk factor for colonization with MRE at discharge, but not at 2 weeks. Analysis within a NICU showed that exposure of an infant to a specific antibiotic in the NICU was not a risk factor for the carriage of a strain resistant to that antibiotic. Estimates of persistence from discharge to 6 months were the following: for tetracycline, 57% (95% confidence intervals [CI], 0.35 to 0.87); chloramphenicol, 49% (95% CI, 0.20 to 0.83); trimethoprim, 45% (95% CI, 0.22 to 0.74); piperacillin-tazobactam, 42% (95% CI, 0.20 to 0.71); and augmentin, 34% (95% CI, 0.11 to 0.66). Strains resistant to cephalosporins or aminoglycosides showed lower levels of persistence. Nine of 34 infants (26.5%) with Escherichia coli and 4 (7.1%) of 56 infants with Klebsiella spp. at discharge carried strains indistinguishable by randomly amplified polymorphic DNA and antibiotic susceptibility patterns at 6 months. MRE were found at high frequency in the infants during their stay in the NICU and persisted in a proportion of infants.

Measuring circulating blood volume in newborn infants using pulse dye densitometry and indocyanine green.

BACKGROUND: Circulating blood volume (BV) is an important, but often unconsidered, variable in newborn infants undergoing intensive care. The data on validation and repeatability of BV measurement are limited. AIM: To validate and test the repeatability of measuring BV in newborn infants using indocyanine green (ICG) and pulse dye densitometry (PDD). METHODS: Validation--Paired measurements of BV were made using the fetal hemoglobin (HbF) dilution and the PDD method. Repeatability--The BV was measured twice at an interval of 30-40 min in a second group of infants. RESULTS: Validation--Data from three of 13 infants studied were excluded because of probe dislodgement or ICG injection error. The median (range) birth weight of the 10 infants whose data were analyzed was 1032 g (740-2384 g) and seven (70%) were receiving either mechanical ventilation or nasal CPAP. The median BV measured by HbF dilution was 66.2 ml x kg(-1) (43.7-81.0 ml x kg(-1)) and by the PDD method was 68.9 ml x kg(-1) (49.3-101.0 ml x kg(-1)). The mean difference was 5.92 ml x kg(-1) (SD 17.33 ml x kg(-1)). Repeatability--Twelve infants were studied and three excluded because of probe dislodgement/motion artifact or ICG injection error. The median weight of the nine infants whose data were analyzed was 1208 g (795-2600 g). The median (range) BV1 and BV2 were 70.5 ml x kg(-1) (53.1-160 ml x kg(-1)) and 87.5 ml x kg(-1) (38.0-248.0 ml x kg(-1)), respectively. Mean difference of the two BV estimates (BV1-BV2) was -24.6 ml x kg(-1) (SD 33.3 ml x kg(-1)) and coefficient of repeatability was 66.5 ml x kg(-1). CONCLUSION: Pulse dye densitometry can be used to measure BV in the newborn infant at the cotside but the repeatability measurements suggest that its use is limited.

Incidence of neonatal necrotising enterocolitis in high-income countries: a systematic review.

OBJECTIVE: To conduct a systematic review of neonatal necrotising enterocolitis (NEC) rates in high-income countries published in peer-reviewed journals. METHODS: We searched MEDLINE, Embase and PubMed databases for observational studies published in peer-reviewed journals. We selected studies reporting national, regional or multicentre rates of NEC in 34 Organisation for Economic Co-operation and Development countries. Two investigators independently screened studies against predetermined criteria. For included studies, we extracted country, year of publication in peer-reviewed journal, study time period, study population inclusion and exclusion criteria, case definition, gestation or birth weight-specific NEC and mortality rates. RESULTS: Of the 1888 references identified, 120 full manuscripts were reviewed, 33 studies met inclusion criteria, 14 studies with the most recent data from 12 countries were included in the final analysis. We identified an almost fourfold difference, from 2% to 7%, in the rate of NEC among babies born <32 weeks' gestation and an almost fivefold difference, from 5% to 22%, among those with a birth weight <1000 g but few studies covered the entire at-risk population. The most commonly applied definition was Bell's stage ≥2, which was used in seven studies. Other definitions included Bell's stage 1-3, definitions from the Centers for Disease Control and Prevention, International Classification for Diseases and combinations of clinical and radiological signs as specified by study authors. CONCLUSION: The reasons for international variation in NEC incidence are an important area for future research. Reliable inferences require clarity in defining population coverage and consistency in the case definition applied. PROSPERO INTERNATIONAL PROSPECTIVE REGISTER OF SYSTEMATIC REVIEWS REGISTRATION NUMBER: CRD42015030046.

The United Kingdom National Neonatal Research Database: A validation study.

BACKGROUND: The National Neonatal Research Database (NNRD) is a rich repository of pre-defined clinical data extracted at regular intervals from point-of-care, clinician-entered electronic patient records on all admissions to National Health Service neonatal units in England, Wales, and Scotland. We describe population coverage for England and assess data completeness and accuracy. METHODS: We determined population coverage of the NNRD in 2008-2014 through comparison with data on live births in England from the Office for National Statistics. We determined the completeness of seven data items on the NNRD. We assessed the accuracy of 44 data items (16 patient characteristics, 17 processes, 11 clinical outcomes) for infants enrolled in the multi-centre randomised controlled trial, Probiotics in Preterm Study (PiPs). We compared NNRD to PiPs data, the gold standard, and calculated discordancy rates using predefined criteria, and sensitivity, specificity and positive predictive values (PPV) of binary outcomes. RESULTS: The NNRD holds complete population data for England for infants born alive from 25+0 to 31+6 (completed weeks) of gestation; and 70% and 90% for those born at 23 and 24 weeks respectively. Completeness of patient characteristics was over 90%. Data were linked for 2257 episodes of care received by 1258 of the 1310 babies recruited to PiPs. Discordancy rates were <5% for 13/16 patient characteristics (exceptions: mode of delivery 8.7%; maternal ethnicity 10.2%, Lower layer Super Output Area 16.5%); <5% for 9/16 processes (exceptions: medical treatment for Patent ductus arteriosus 6.1%, high-dependency days 10.2%, central line days 11.2%, type of first milk 22.3%; and during first 14 days, summary of types of milk 13.8%; number of days of antibiotics 9.0%; whether antacid given 5.1%); and <5% for 10/11 clinical outcomes (exception: Bronchopulmonary dysplasia, defined as oxygen dependency at 36 weeks postmenstrual age 3.3%). The specificity of NNRD data was >85% for all outcomes; sensitivity ranged from 50-100%; PPV ranged from 58.8 (95% CI 40.8-75.4%) for porencephalic cyst to 99.7 (95% CI 99.2, 99.9%) for survival to discharge. CONCLUSIONS: The completeness and quality of data held in the NNRD is high, providing assurance in relation to use for multiple purposes, including national audit, health service evaluations, quality improvement, and research.

Development of a Gestational Age-Specific Case Definition for Neonatal Necrotizing Enterocolitis.

Importance: Necrotizing enterocolitis (NEC) is a major cause of neonatal morbidity and mortality. Preventive and therapeutic research, surveillance, and quality improvement initiatives are hindered by variations in case definitions. Objective: To develop a gestational age (GA)-specific case definition for NEC. Design, Setting, and Participants: We conducted a prospective 34-month population study using clinician-recorded findings from the UK National Neonatal Research Database between December 2011 and September 2014 across all 163 neonatal units in England. We split study data into model development and validation data sets and categorized GA into groups (group 1, less than 26 weeks' GA; group 2, 26 to less than 30 weeks' GA; group 3, 30 to less than 37 weeks' GA; group 4, 37 or more weeks' GA). We entered GA, birth weight z score, and clinical and abdominal radiography findings as candidate variables in a logistic regression model, performed model fitting 1000 times, averaged the predictions, and used estimates from the fitted model to develop an ordinal NEC score and cut points to develop a dichotomous case definition based on the highest area under the receiver operating characteristic curves [AUCs] and positive predictive values [PPVs]. Exposures: Abdominal radiography performed to investigate clinical concerns. Main Outcomes and Measures: Ordinal NEC likelihood score, dichotomous case definition, and GA-specific probability plots. Results: Of the 3866 infants, the mean (SD) birth weight was 2049.1 (1941.7) g and mean (SD) GA was 32 (5) weeks; 2032 of 3663 (55.5%) were male. The total included 2978 infants (77.0%) without NEC and 888 (23.0%) with NEC. Infants with NEC in group 1 were less likely to present with pneumatosis (31.1% vs 47.2%; P = .01), blood in stool (11.8% vs 29.6%; P < .001), or mucus in stool (2.1% vs 5.6%; P = .048) but more likely to present with gasless abdominal radiography findings (6.3% vs 0.9%; P = .009) compared with infants with NEC in group 3. In the ordinal NEC score analysis, we allocated 3 points to pneumatosis, 2 points to blood in stool, and 1 point each to abdominal tenderness and abdominal discoloration; 1 point was assigned if 1 or more of pneumoperitoneum, fixed loop, and portal venous gas were present, and 1 point was assigned if both increased and/or bilious aspirates and abdominal distension were present. The cutoff scores for the dichotomous GA-specific case definition were 2 or greater for infants in groups 1 and 2, 3 or greater for infants in group 3, and 4 or greater for infants in group 4. The ordinal NEC score and dichotomous case definition discriminated well between infants with (AUC, 87%) and without (AUC, 80%) NEC. The case definition has a sensitivity of 66.2% (95% CI, 63.0-69.4), a specificity of 94.4% (95% CI, 93.2-95.4), an AUC of 80.0% (95% CI, 79-82), and a PPV of 85.5% (95% CI, 82.6-88.1). Applying the cut points to the 431 infants who underwent a laparotomy yielded a sensitivity of 76.5% (95% CI, 70.0-82.1), a specificity of 74.4% (95% CI, 68.3-80.0), an AUC of 75.0% (95% CI, 71.0- 80.0), and a PPV of 72.9% (95% CI, 66.4-78.7). Conclusions and Relevance: The risk of NEC and clinical presentation are associated with GA. Adoption of a consistent GA-specific case definition would strengthen global efforts to reduce the population burden of this devastating neonatal disease.

Incidence and enteral feed antecedents of severe neonatal necrotising enterocolitis across neonatal networks in England, 2012-13: a whole-population surveillance study.

BACKGROUND: Necrotising enterocolitis is a neonatal gastrointestinal inflammatory disease with high mortality and severe morbidity. This disorder is growing in global relevance as birth rates and survival of babies with low gestational age improve. Population data are scant and pathogenesis is incompletely understood, but enteral feed exposures are believed to affect risk. We aimed to quantify the national incidence of severe necrotising enterocolitis, describe variation across neonatal networks, and investigate enteral feeding-related antecedents of severe necrotising enterocolitis. METHODS: We undertook a 2-year national surveillance study (the UK Neonatal Collaborative Necrotising Enterocolitis [UKNC-NEC] Study) of babies born in England to quantify the burden of severe or fatal necrotising enterocolitis confirmed by laparotomy, leading to death, or both. Data on all liveborn babies admitted to neonatal units between Jan 1, 2012, and Dec 31, 2013, were obtained from the National Neonatal Research Database. In the subgroup of babies born before a gestational age of 32 weeks, we did a propensity score analysis of the effect of feeding in the first 14 postnatal days with own mother's milk, with or without human donor milk and avoidance of bovine-origin formula, or milk fortifier, on the risk of developing necrotising enterocolitis. FINDINGS: During the study period, 118 073 babies were admitted to 163 neonatal units across 23 networks, of whom 14 678 were born before a gestational age of 32 weeks. Overall, 531 (0·4%) babies developed severe necrotising enterocolitis, of whom 247 (46·5%) died (139 after laparotomy). 462 (3·2%) of 14 678 babies born before a gestational age of 32 weeks developed severe necrotising enterocolitis, of whom 222 (48·1%) died. Among babies born before a gestational age of 32 weeks, the adjusted network incidence of necrotising enterocolitis ranged from 2·51% (95% CI 1·13-3·60) to 3·85% (2·37-5·33), with no unusual variation from the adjusted national incidence of 3·13% (2·85-3·42), despite variation in feeding practices. The absolute risk difference for babies born before a gestational age of 32 weeks who received their own mother's milk within 7 days of birth was -0·88% (95% CI -1·15 to -0·61; relative risk 0·69, 95% CI 0·60 to 0·78; number needed to treat to prevent one case of necrotising enterocolitis 114, 95% CI 87 to 136). For babies who received no compared with any bovine-origin products within 14 days of birth, the absolute risk difference was -0·65% (-1·01 to -0·29; relative risk 0·61, 0·39 to 0·83; number needed to treat 154, 99 to 345). We were unable to assess the effect of human donor milk as use was low. INTERPRETATION: Early feeding of babies with their own mother's milk and avoidance of bovine-origin products might reduce the risk of necrotising enterocolitis, but the absolute reduction is small. Owing to the rarity of severe necrotising enterocolitis, international collaborations are needed for adequately powered preventive trials. FUNDING: National Institute for Health Research.

The Microbiome of Infants Recruited to a Randomised Placebo-controlled Probiotic Trial (PiPS Trial).

The microbial dysbiosis associated with necrotizing enterocolitis (NEC) in preterm infants suggests that early exposure to probiotics may decrease and antibiotics may increase NEC risk. However, administration of Bifidobacterium breve strain BBG-001 to preterm infants did not affect NEC incidence in a multicenter randomised controlled phase 3 trial (PiPS trial). Using a subset of these subjects we compared the fecal microbiome of probiotic and placebo groups and assessed the impact of early antibiotic treatment. Extracted DNA from 103 fecal samples collected at 36weeks post-menstrual age underwent PCR amplification of a fragment of the 16S rRNA gene. Heatmaps were constructed showing the proportions of sequences from bacterial families present at >1% of the community. Stepwise logistic regression assessed the association between early antibiotic exposure and microbiome group. There was no difference in the microbial richness and diversity of the microbiome of preterm infants following treatment with probiotic or a placebo. Conversely, early antimicrobial exposure was associated with different patterns of colonisation, specifically a relative abundance of Proteobacteria. These findings highlight that the potential influence of probiotics on the microbiome of preterm infants remains unclear whereas the modulatory effect of antibiotic exposure on microbial colonisation requires further research.

A randomised controlled trial of the probiotic Bifidobacterium breve BBG-001 in preterm babies to prevent sepsis, necrotising enterocolitis and death: the Probiotics in Preterm infantS (PiPS) trial.

BACKGROUND: Necrotising enterocolitis (NEC) and late-onset sepsis remain important causes of death and morbidity in preterm babies. Probiotic administration might strengthen intestinal barrier function and provide protection; this is supported by published meta-analyses, but there is a lack of large well-designed trials. OBJECTIVE: To test the use of the probiotic Bifidobacterium breve strain BBG-001 to prevent NEC, late-onset sepsis and death in preterm babies while monitoring probiotic colonisation of participants. DESIGN: Double-blind, randomised, placebo-controlled trial. SETTING: Recruitment was carried out in 24 hospitals, and the randomisation programme used a minimisation algorithm. Parents, clinicians and outcome assessors were blinded to the allocation. PARTICIPANTS: Babies born between 23 and 30 weeks' gestation and randomised within 48 hours of birth. Exclusions included life-threatening or any gastrointestinal malformation detected within 48 hours of birth and no realistic chance of survival. INTERVENTIONS: Active intervention: 1 ml of B. breve BBG-001 in one-eighth-strength infant formula Neocate(®) (Nutricia Ltd, Trowbridge, UK), (6.7 × 10(7) to 6.7 × 10(9) colony-forming units) per dose administered enterally. Placebo: 1 ml of one-eighth-strength infant formula Neocate. Started as soon as practicable and continued daily until 36 weeks' postmenstrual age. MAIN OUTCOME MEASURES: Primary outcomes were an episode of bloodstream infection, with any organism other than a skin commensal, in any baby between 72 hours and 46 weeks' postmenstrual age; an episode of NEC Bell stage ≥ 2 in any baby; and death before discharge from hospital. Secondary outcomes included stool colonisation with B. breve. RESULTS: In total, 654 babies were allocated to receive probiotic and 661 to receive placebo over 37 months from July 2010. Five babies were withdrawn; 650 babies from the probiotic group and 660 from the placebo group were included in the primary analysis. Baseline characteristics were well balanced. There was no evidence of benefit for the primary outcomes {sepsis: 11.2% vs. 11.7% [adjusted relative risk (RR) 0.97, 95% confidence interval (CI) 0.73 to 1.29]; NEC Bell stage ≥ 2: 9.4% vs. 10.0% [adjusted RR 0.93, 95% CI 0.68 to 1.27]; and death: 8.3% vs. 8.5% [adjusted RR 0.93, 95% CI 0.67 to 1.30]}. B. breve colonisation status was available for 1186 (94%) survivors at 2 weeks' postnatal age, of whom 724 (61%) were positive: 85% of the probiotic group and 37% of the placebo group. There were no differences for subgroup analyses by minimisation criteria and by stool colonisation with B. breve at 2 weeks. No harms associated with the interventions were reported. LIMITATIONS: Cross-colonisation of the placebo arm could have reduced statistical power and confounded results; analyses suggest that this did not happen. CONCLUSIONS: This is the largest trial to date of a probiotic intervention. It shows no evidence of benefit and does not support routine use of probiotics for preterm infants. FUTURE WORK RECOMMENDATIONS: The increasing understanding of the pathogenesis of NEC and sepsis will inform the choice of probiotics for testing and better define the target population. Future Phase III trials should incorporate monitoring of the quality and viability of the intervention and colonisation rates of participants; cluster design should be considered. TRIAL REGISTRATION: Current Controlled Trials ISRCTN05511098 and EudraCT 2006-003445-17. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 66. See the NIHR Journals Library website for further project information.