Time of Onset of Necrotizing Enterocolitis and Focal Perforation in Preterm Infants: Impact on Clinical, Surgical, and Histological Features.

Objective: There is no gold standard test for diagnosis of necrotizing enterocolitis (NEC). Timing of onset is used in some definitions and studies in an attempt to separate NEC from focal intestinal perforation (FIP) with 14 days used as a cutoff. In a large, detailed data set we aimed to compare NEC and FIP in preterm infants born <32 weeks gestation, presenting before 14 days of life in comparison to cases presenting later. Design: Infants with NEC or FIP when parents had consented to enrollment in an observational and sample collection study were included from 2009 to 2019. Clinical, surgical, histological, and outcome data were extracted and reviewed by each author independently. Patients/Episodes: In 785 infants, 174 episodes of NEC or FIP were identified of which 73 (42%) occurred before 14 days, including 54 laparotomies and 19 episodes of medically managed NEC ("early"). There were 56 laparotomies and 45 episodes of medically managed NEC presenting on or after 14 days age ("late"). Results: In early cases, 41% of laparotomies were for NEC (22 cases) and 59% for FIP (32 cases), and in late cases, 91% of laparotomies (51 cases) were for NEC and 9% (five cases) were for FIP. NEC presenting early was more likely to present with an initial septic presentation rather than discrete abdominal pathology and less likely to have clear pneumatosis. Early cases did not otherwise differ clinically, surgically, or histologically or in outcomes compared with later cases. FIP features did not differ by age at presentation. Conclusions: Although most FIP occurred early, 14% occurred later, whereas almost one third (29%) of NEC cases (surgical and medical) presented early. Infant demographics and surgical and histological findings of early- and late-presenting disease did not differ, suggesting that early and late cases are not necessarily different subtypes of the same disease although a common pathway of different pathogenesis cannot be excluded. Timing of onset does not accurately distinguish NEC from FIP, and caution should be exercised in including timing of onset in diagnostic criteria.

ELFIN, the United Kingdom preterm lactoferrin trial: interpretation and future questions 1.

Results from previous studies have suggested that supplemental bovine lactoferrin (BLF) given to preterm infants (<32 weeks gestation) reduces late-onset sepsis (LOS) and necrotising enterocolitis (NEC). The Enteral Lactoferrin in Neonates (ELFIN) study, performed in the UK, aimed to further address this issue with a well powered double-blind placebo controlled trial of >2200 preterm infants. The results from ELFIN did not demonstrate a reduction in LOS or NEC, or several other clinically important measures. Of the 1093 infants, 316 (29%) in the intervention group developed late-onset sepsis versus 334 (31%) of 1089 in the control group, with an adjusted risk ratio of 0.95 (95% CI = 0.86-1.04; p = 0.233). Reasons for the differences in ELFIN trial results and other studies may include population differences, the routine use of antifungal prophylaxis in the UK, timing of administration of the lactoferrin in relation to disease onset, or specific properties of the lactoferrin used in the different trials. The UK National Institutes for Health Research funded "Mechanisms Affecting the Guts of Preterm Infants in Enteral feeding trials" (MAGPIE) study is further exploring the use of lactoferrin, and the results should be available soon.

Economic evaluation alongside the Speed of Increasing milk Feeds Trial (SIFT).

OBJECTIVE: To evaluate the cost-effectiveness of two rates of enteral feed advancement (18 vs 30 mL/kg/day) in very preterm and very low birth weight infants. DESIGN: Within-trial economic evaluation alongside a multicentre, two-arm parallel group, randomised controlled trial (Speed of Increasing milk Feeds Trial). SETTING: 55 UK neonatal units from May 2013 to June 2015. PATIENTS: Infants born <32 weeks' gestation or <1500 g, receiving less than 30 mL/kg/day of milk at trial enrolment. Infants with a known severe congenital anomaly, no realistic chance of survival, or unlikely to be traceable for follow-up, were ineligible. INTERVENTIONS: When clinicians were ready to start advancing feed volumes, infants were randomised to receive daily increments in feed volume of 30 mL/kg (intervention) or 18 mL/kg (control). MAIN OUTCOME MEASURE: Cost per additional survivor without moderate to severe neurodevelopmental disability at 24 months of age corrected for prematurity. RESULTS: Average costs per infant were slightly higher for faster feeds compared with slower feeds (mean difference £267, 95% CI -6928 to 8117). Fewer infants achieved the principal outcome of survival without moderate to severe neurodevelopmental disability at 24 months in the faster feeds arm (802/1224 vs 848/1246). The stochastic cost-effectiveness analysis showed a likelihood of worse outcomes for faster feeds compared with slower feeds. CONCLUSIONS: The stochastic cost-effectiveness analysis shows faster feeds are broadly equivalent on cost grounds. However, in terms of outcomes at 24 months age (corrected for prematurity), faster feeds are harmful. Faster feeds should not be recommended on either cost or effectiveness grounds to achieve the primary outcome.

The future of probiotics in the preterm infant.

Probiotic administration to preterm infants is not universal despite randomised trial data from >10,000 infants, significant observational data and multiple meta-analyses. Advocates point to reductions in necrotising enterocolitis and sepsis, 'sceptics' hold concerns over data quality/interpretation or risks. Issues revolve around different products, primary outcomes, uncertain dosing strategies and individual large 'negative' trials alongside probiotic associated sepsis and quality control concerns. We review concerns and how to move probiotic use forward. Surprisingly little is known about parental perspectives, vital to inform next steps. How to share information and decisions around probiotic use now, and how this impacts on future available strategies is discussed. We address placebo controlled trials and propose alternate designs, including head to head studies, using 'routine' data collection systems, opt out consents and 'learning technologies' embedded in health care systems. We also raise the importance of underpinning mechanistic work to inform future trials.

Proportionate reduction in uncertainty of late onset infection in pre-term infants by neutrophil CD64 measurement.

OBJECTIVE: Establish how neutrophil CD64 performs as a marker of definite infection in pre-term infants in comparison to C reactive protein (CRP) and procalcitonin (PCT). METHODS: A total of 38 pre-term infants with suspected late onset infection had CD64 measured by flow cytometry. Proportionate reduction in uncertainty (PRU) curves were generated for CD64 counts at various threshold values. RESULTS: PRU curves reduced the residual uncertainty of the presence of infection by up to 64%. CONCLUSIONS: The CD64 appears to be a useful point of care test (POCT) for further defining the likelihood of infection and performs better than CRP or PCT at helping to rule in infection.

Bacterial and fungal viability in the preterm gut: NEC and sepsis.

BACKGROUND AND AIMS: Evidence suggests that microbial communities in the preterm gut may influence the development of necrotising enterocolitis (NEC) and sepsis. Existing data often neglect fungi and whether bacteria were metabolically active or not. We sought to characterise the bacterial and fungal stool flora of preterm neonates and organism viability and evaluate any associations with NEC and sepsis. PATIENTS: 136 stools from 32 patients (<32 weeks gestation) were collected between birth and day 95. Seven infants developed NEC and 13 sepsis. METHODS: Stools were analysed by PCR-DGGE for assessment of the total bacterial and fungal communities by analysis of 16S rRNA and 28S rRNA, respectively. In 65 samples (25 infants), the viable (RNA) bacterial and fungal communities were analysed. Analyses were performed to examine the possible effects of demographic or treatment related factors and the development of NEC or sepsis. RESULTS: 80 (66 viable) bacterial species were identified overall and 12 fungal (none viable). Total bacterial communities significantly differed between healthy infants and those with NEC or sepsis, with Sphingomonas spp. significantly associated with NEC. Significant drivers of community structure differed based on either total or viable analysis. Antifungal prophylaxis was associated with altered bacterial community and a reduction in bacterial richness was observed in week 4, correlating with high antibiotic exposure. CONCLUSIONS: Total and viable communities differ in preterm infants, and non-viable fungal species are present in infants on fungal prophylaxis. Exploration of viability and non-bacterial contributors to the total community may increase understanding of NEC and sepsis.

Deaths in preterm infants: changing pathology over 2 decades.

OBJECTIVE: To establish how cause of death for live-born preterm infants (24-31 weeks gestation) has changed in a single large UK population over 2 decades. STUDY DESIGN: This was an interrogation of a population-based survey of >680, 000 live births (between 1988 and 2008) for deaths in the first postnatal year. We collected cause of death grouped into major etiologies: respiratory, infection, malformation, necrotizing enterocolitis (NEC), and other. Data were analyzed in three 7-year epochs and 2 gestational groups (<27 and 28-31 weeks). Numbers, rates per 1000 live births, and proportional contributions to each epoch were analyzed. RESULTS: A total of 1504 deaths occurred. The infants who died had a median gestational age of 26 weeks (IQR, 25-28 weeks) and a median birth weight of 880 g (IQR, 700-1170 g). The number of deaths decreased with each later epoch (from 671 to 473 and then to 360), as did the proportion of deaths from respiratory causes (64% to 62% and then to 49%). The proportion of deaths occurring after 40 weeks postmenstrual age remained stable across the 3 epochs (8.8%, 8%, and 8%). Deaths from infection and NEC increased with time (from 11% to 13% and then to 21%), as did median time to death (from 2.7 to 3.8 days). CONCLUSION: Infection and NEC are increasingly prevalent causes of death in preterm infants.