Oral lactoferrin for the prevention of sepsis and necrotizing enterocolitis in preterm infants

Effective alternatives for dietary interventions for necrotizing enterocolitis: a systematic review of in vivo studies

Necrotizing enterocolitis (NEC) is a significant cause of morbidity and mortality among neonates and low birth weight children in the United States. Current treatment options, such as antibiotics and intestinal resections, often result in complications related to pediatric nutrition and development. This systematic review aimed to identify alternative dietary bioactive compounds that have shown promising outcomes in ameliorating NEC in vivo studies conducted within the past six years. Following PRISMA guidelines and registering in PROSPERO (CRD42023330617), we conducted a comprehensive search of PubMed, Scopus, and Web of Science. Our analysis included 19 studies, predominantly involving in vivo models of rats (Rattus norvegicus) and mice (Mus musculus). The findings revealed that various types of compounds have demonstrated successful amelioration of NEC symptoms. Specifically, six studies employed plant phenolics, seven utilized plant metabolites/cytotoxic chemicals, three explored the efficacy of vitamins, and three investigated the potential of whole food extracts. Importantly, all administered compounds exhibited positive effects in mitigating the disease. These results highlight the potential of natural cytotoxic chemicals derived from medicinal plants in identifying and implementing powerful alternative drugs and therapies for NEC. Such approaches have the capacity to impact multiple pathways involved in the development and progression of NEC symptoms.

Probiotics, Prebiotics, Lactoferrin, and Combination Products for Prevention of Mortality and Morbidity in Preterm Infants: A Systematic Review and Network Meta-Analysis

Importance

Modulation of intestinal microbiome by administering probiotics, prebiotics, or both may prevent morbidity and mortality in premature infants.

Objective

To assess the comparative effectiveness of alternative prophylactic strategies through a network meta-analysis (NMA) of randomized clinical trials.

Data Sources

MEDLINE, EMBASE, Science Citation Index Expanded, CINAHL, Scopus, Cochrane CENTRAL, and Google Scholar from inception until May 10, 2023.

Study Selection

Eligible trials tested probiotics, prebiotics, lactoferrin, and combination products for prevention of morbidity or mortality in preterm infants.

Data Extraction and Synthesis

A frequentist random-effects model was used for the NMA, and the certainty of evidence and inferences regarding relative effectiveness were assessed using the GRADE approach.

Main Outcomes and Measures

All-cause mortality, severe necrotizing enterocolitis, culture-proven sepsis, feeding intolerance, time to reach full enteral feeding, and duration of hospitalization.

Results

A total of 106 trials involving 25 840 preterm infants were included. Only multiple-strain probiotics were associated with reduced all-cause mortality compared with placebo (risk ratio [RR], 0.69; 95% CI, 0.56 to 0.86; risk difference [RD], -1.7%; 95% CI, -2.4% to -0.8%). Multiple-strain probiotics alone (vs placebo: RR, 0.38; 95% CI, 0.30 to 0.50; RD, -3.7%; 95% CI, -4.1% to -2.9%) or in combination with oligosaccharides (vs placebo: RR, 0.13; 95% CI, 0.05 to 0.37; RD, -5.1%; 95% CI, -5.6% to -3.7%) were among the most effective interventions reducing severe necrotizing enterocolitis. Single-strain probiotics in combination with lactoferrin (vs placebo RR, 0.33; 95% CI, 0.14 to 0.78; RD, -10.7%; 95% CI, -13.7% to -3.5%) were the most effective intervention for reducing sepsis. Multiple-strain probiotics alone (RR, 0.61; 95% CI, 0.46 to 0.80; RD, -10.0%; 95% CI, -13.9% to -5.1%) or in combination with oligosaccharides (RR, 0.45; 95% CI, 0.29 to 0.67; RD, -14.1%; 95% CI, -18.3% to -8.5%) and single-strain probiotics (RR, 0.61; 95% CI, 0.51 to 0.72; RD, -10.0%; 95% CI, -12.6% to -7.2%) proved of best effectiveness in reduction of feeding intolerance vs placebo. Single-strain probiotics (MD, -1.94 days; 95% CI, -2.96 to -0.92) and multistrain probiotics (MD, -2.03 days; 95% CI, -3.04 to -1.02) proved the most effective in reducing the time to reach full enteral feeding compared with placebo. Only single-strain and multistrain probiotics were associated with greater effectiveness compared with placebo in reducing duration of hospitalization (MD, -3.31 days; 95% CI, -5.05 to -1.58; and MD, -2.20 days; 95% CI, -4.08 to -0.31, respectively).

Conclusions and Relevance

In this systematic review and NMA, moderate- to high-certainty evidence demonstrated an association between multistrain probiotics and reduction in all-cause mortality; these interventions were also associated with the best effectiveness for other key outcomes. Combination products, including single- and multiple-strain probiotics combined with prebiotics or lactoferrin, were associated with the largest reduction in morbidity and mortality.

Transcriptomic analysis identifies lactoferrin-induced quiescent circuits in neonatal macrophages

Introduction

Upon birth, a hitherto naïve immune system is confronted with a plethora of microbial antigens due to intestinal bacterial colonization. To prevent excessive inflammation and disruption of the epithelial barrier, physiological mechanisms must promote immune-anergy within the neonatal gut. As high concentrations of human lactoferrin (hLF), a transferrin glycoprotein shown to modulate macrophage function, are frequently encountered in colostrum, its direct interaction with intestinal macrophages may satisfy this physiological need. Thus, the primary objective of this study was to investigate transcriptional changes induced by human lactoferrin in neonatal monocyte-derived macrophages.

Methods

Cord blood-derived monocytes were differentiated with M-CSF in presence or absence of 500 µg/mL hLF for 7 days and afterwards stimulated with 1 ng/mL LPS or left untreated. RNA was then isolated and subjected to microarray analysis.

Results

Differentiation of cord blood-derived monocytes in presence of hLF induced a distinct transcriptional program defined by cell cycle arrest in the G2/M phase, induction of IL-4/IL-13-like signaling, altered extracellular matrix interaction, and enhanced propensity for cell-cell interaction. Moreover, near-complete abrogation of transcriptional changes induced by TLR4 engagement with LPS was observed in hLF-treated samples.

Discussion

The global transition towards an M2-like homeostatic phenotype and the acquisition of quiescence elegantly demonstrate the ontogenetical relevance of hLF in attenuating pro-inflammatory signaling within the developing neonatal intestine. The marked anergy towards proinflammatory stimuli such as LPS further underlines the glycoprotein's potential therapeutic relevance.

Featured Prebiotic Agent: The Roles and Mechanisms of Direct and Indirect Prebiotic Activities of Lactoferrin and Its Application in Disease Control

Lactoferrin (LF) is a glycoprotein found in mammalian milk, and lactoferricin is a peptide derived from LF hydrolysate. Both LF and lactoferricin (LFcin) have diverse functions that could benefit mammals. Bovine LF (BLF) and BLFcin exhibit a wide range of antimicrobial activities, but most probiotic strains are relatively resistant to their antibacterial effects. BLF and BLF hydrolysate can promote the growth of specific probiotics depending on the culture conditions, the dose of BLF or BLF-related peptides, and the probiotic strains used. BLF supplementation has been shown to modulate several central molecular pathways or genes in Lacticaseibacillus rhamnosus GG under cold conditions, which may explain the prebiotic roles of BLF. LF alone or in combination with selected probiotics can help control bacterial infections or metabolic disorders, both in animal studies and in human clinical trials. Various LF-expressing probiotics, including those expressing BLF, human LF, or porcine LF, have been developed to facilitate the combination of LFs with specific probiotics. Supplementation with LF-expressing probiotics has positive effects in animal studies. Interestingly, inactivated LF-expressing probiotics significantly improved diet-induced nonalcoholic fatty liver disease (NAFLD) in a mouse model. This review highlights the accumulated evidence supporting the use of LF in combination with selected LF-resistant probiotics or LF-expressing probiotics in the field.

Bovine Colostrum Treatment of Specific Cancer Types: Current Evidence and Future Opportunities

Worldwide, the incidence of cancer is on the rise. Current cancer treatments include chemotherapy, radiation therapy, and surgery. Chemotherapy and radiation treatment are typically associated with severe adverse effects and a decline in patients' quality of life. Anti-cancer substances derived from plants and animals need to be evaluated therapeutically as it is cost-effective, have fewer side effects, and can improve cancer patients' quality of life. Recently, bovine colostrum (BC) has attracted the interest of numerous researchers investigating its anti-cancer potential in humans. Dressings loaded with BC are beneficial in treating chronic wounds and diabetic foot ulcers. Lactoferrin, a glycoprotein with potent anti-oxidant, anti-inflammatory, anti-cancer, and anti-microbial effects, is abundant in BC. The BC pills successfully promote the regression of low-grade cervical intraepithelial neoplasia when administered intravaginally. The biological, genetic, and molecular mechanisms driving BC remain to be determined. Oral BC supplements are generally well-tolerated, but some flatulence and nausea may happen. To evaluate the therapeutic effects, long-term safety, and appropriate dosages of BC drugs, well-designed clinical trials are necessary. The purpose of this article is to emphasize the anti-cancer potential of BC and its constituents.

Colostrum Use and the Immune System of Premature Newborns: A Systematic Review and Meta-Analysis

BACKGROUND

Human colostrum has been used in a number of investigations when preterm human infants cannot, for any reason, breastfeed directly from their mothers. One of the growing fields in these investigations is colostrum therapy, which consists of exposing the oropharyngeal mucosa of these preterm newborns to small amounts of raw colostrum.

RESEARCH AIM

To critically review the scientific evidence about colostrum therapy in premature infants and to explore its influences on the immune system.

METHODS

This systematic review was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA statement). The following databases were searched for potentially eligible studies up to March 10, 2021: Medline, Scopus, Web of Science, Cochrane Library, Embase. Two reviewers independently screened all titles, abstracts, and full texts for eligibility.

RESULTS

A total of 12 studies with 996 participants were included. A significant difference in lactoferrin levels in the urine was found (SMD 0.70; 95% CI [0.03,1.36]; p = .04; I² = 65% two studies, 112 participants, very low-quality evidence).

CONCLUSION

Colostrum seems to result in increasing lactoferrin levels in the urine of premature newborns after 1 week of intervention.

CLINICAL TRIAL REGISTRATION

The study was registered at PROSPERO with the number CRD42017073624, submitted on August 9, 2017.

Lactoferrin and Human Neutrophil Protein (HNP) 1-3 Levels During the Neonatal Period in Preterm Infants

Antimicrobial polypeptides (APPs) are part of the innate immune system, but their specific role in the context of preterm birth is not yet understood. The aim of this investigation was to determine the systemic expression of APPs, i.e., lactoferrin (LF) and human neutrophil protein (HNP) 1-3 in preterm infants in the period of highest vulnerability for infection and to correlate these biomarkers with short-term outcome. We therefore conducted a prospective two-center study including plasma samples of 278 preterm infants and 78 corresponding mothers. APP levels were analyzed on day 1, 3, 7, and 21 of life via enzyme-linked immunosorbent assay (ELISA). The levels of LF and HNP1-3 remained stable during the first 21 days of life and were not influenced by maternal levels. Elevated APP levels were found at day 1 in infants born to mothers with amniotic infection syndrome (AIS vs. no AIS, mean ± SD in ng/ml: LF 199.8 ± 300 vs. 124.1 ± 216.8, HNP 1-3 16,819 ± 36,124 vs. 8,701 ± 11,840; p = 0.021, n = 179). We found no elevated levels of APPs before the onset of sepsis episodes or in association with other short-term outcomes that are in part mediated by inflammation such as necrotizing enterocolitis (NEC) or retinopathy of prematurity (ROP). Interestingly, infants developing bronchopulmonary dysplasia (BPD) showed higher levels of HNP1-3 on day 21 than infants without BPD (13,473 ± 16,135 vs. 8,388 ± 15,938, n = 111, p = 0.008). In infants born without amniotic infection, levels of the measured APPs correlated with gestational age and birth weight. In our longitudinal study, systemic levels of LF and HNP 1-3 were not associated with postnatal infection and adverse short-term outcomes in preterm infants.

Diverse Immune Effects of Bovine Colostrum and Benefits in Human Health and Disease

The health benefits of bovine colostrum have extensively been studied, including immune effects mediated by immunoglobulins, lactoferrin, and casein, as well as by certain growth factors. Some of these effects are not directly related to the absorption of proteins from the intestinal tract. The ingestion of BC can modulate the function of subsets of lymphocytes, macrophages, and dendritic cells and increase regulatory cytokines such as interleukin 10. In this review, we predominantly focused on evidence from human studies on benefits in health and disease. This review highlights that clear evidence of the prevention of infectious diseases in pre-term infants such as necrotizing enterocolitis, neonatal sepsis or prevention of cancer metastasis is lacking. This is clearly an area where translational science has to be strengthened, taking the considerable evidence from numerous ex vivo studies on cells and tissues and from animal interventions. The review focuses predominantly on human data.

Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is an inflammatory disease affecting premature infants. Intestinal microbial composition may play a key role in determining which infants are predisposed to NEC and when infants are at highest risk of developing NEC. It is unclear how to optimize antibiotic therapy in preterm infants to prevent NEC and how to optimize antibiotic regimens to treat neonates with NEC. This article discusses risk factors for NEC, how dysbiosis in preterm infants plays a role in the pathogenesis of NEC, and how probiotic and antibiotic therapy may be used to prevent and/or treat NEC and its sequelae.

Dose effect of bovine lactoferrin fortification on diarrhea and respiratory tract infections in weaned infants with anemia: A randomized, controlled trial

OBJECTIVE

The aim of this study was to explore the dose effect of bovine lactoferrin (bLF) fortification on the morbidity of diarrhea and respiratory tract infections in weaned infants with anemia.

METHODS

A total of 108 infants with anemia, who were exclusively breast fed at 4 to 6 mo and weaned and formula fed at 6 to 9 mo, were recruited. The eligible infants were randomly assigned to fortified group 0 (FG0), fortified group 1 (FG1), or fortified group 2 (FG2) and were given formula fortified with 0 mg/100 g, 38 mg/100 g, and 76 mg/100 g of bLF, respectively, for 3 mo. The morbidity of diarrhea and respiratory tract infections (RTIs), the duration of respiratory and diarrhea-related illnesses, and the levels of fecal human beta-defensin 2 (HBD-2), cathelicidin LL-37 (LL-37), secretory IgA (sIgA), butyrate, and calprotectin were assessed.

RESULTS

After the exclusion of 12 dropouts, the primary outcome measures, including episodes and duration of diarrhea and RTIs during the intervention, were obtained from 96 infants (35, 33, and 28 in FG0, FG1, and FG2, respectively). Compared with infants in FG0, there was a lower morbidity of rhinorrhea, wheezing, and skin rash among infants in FG1 (P < 0.05) and a lower morbidity of respiratory-related illness and wheezing among infants in FG2 (P < 0.05). Furthermore, a lower morbidity of diarrhea-related illness, diarrhea, vomiting, and nausea was observed among infants in FG2 than those in the other two groups (P < 0.05). In addition, the FG1 infants had a lower morbidity of vomiting and nausea than the FG0 infants (P < 0.05). The HBD-2, LL-37, sIgA, and calprotectin levels were significantly higher whereas the butyrate level was significantly lower in the FG2 infants than in infants in the other two groups after 3 mo of intervention (P < 0.05).

CONCLUSIONS

The bLF-fortified formula was effective in reducing the morbidity of diarrhea and RTIs in infants with anemia, with the 76 mg/100 g bLF-fortified formula exhibiting a stronger effect. The bLF fortification could be a new strategy for the prevention of diarrhea and RTIs in infants with anemia.

Breastfeeding importance and its therapeutic potential against SARS-CoV-2

During postnatal development, colostrum and breastmilk are sequentially the first sources of nutrition with protein components and bioactive molecules that confer protection and immunostimulatory function to the gut. Caseins, whey proteins, secretory immunoglobulin A (sIgA), mucins, tryptophan, and growth factors are among milk‐borne elements that are directly important in the control of mucosa development and protection. Consequently, breastfeeding is associated with the low incidence of gastrointestinal inflammation and with the decrease in respiratory diseases during postnatal period. The novel coronavirus (SARS‐CoV‐2) binds to angiotensin II‐converting enzyme (ACE2) on the cell membrane, allowing virus entrance, replication, and host commitment. ACE2 is expressed by different cell types, which include ciliated cells in the lungs and enterocytes in the intestine. Such cells are highly active in metabolism, as they internalize molecules to be processed and used by the organism. The disruption of ACE2 impairs leads to intestinal inflammation and decreased synthesis of serotonin, affecting motility. By reviewing the effects of SARS‐CoV‐2 in the gastrointestinal and respiratory tracts in infants, and gut responses to breastfeeding interruption, we suggest that it is important to maintain breastfeeding during SARS‐CoV‐2 infection, as it might be essential to protect newborns from gastrointestinal‐associated disorders and relieve disease symptoms.

Therapeutic Applications of Human and Bovine Colostrum in the Treatment of Gastrointestinal Diseases and Distinctive Cancer Types: The Current Evidence

The incidence of gastrointestinal disorders (GID) and cancers is escalating all over the world. Limited consumption of colostrum by newborns not only weakens the immune system but also predisposes infants to microbial infections. Colostrum is nature's perfect food, sometimes referred to as the 'elixir of life'. Breast-fed infants have a lower incidence of GI tract infections than infants fed formula or cow's milk. As per WHO statistics, cancer is the most prevalent disease globally and causes 9.6 million deaths worldwide. The current strategies for treating cancer include chemotherapy, radiation, and surgery. However, chemotherapy and radiation exposure are usually associated with serious long-term side effects and deterioration in the quality of life (QOL) of patients. Furthermore, the hospitalization and medication costs for treating cancers are exorbitant and impose high economic burden on healthcare systems. People are desperately looking for cost-effective and affordable alternative therapies for treating GID and cancers. Therefore, there is an urgent need for clinically evaluating the anticancer compounds isolated from plants and animals. Such therapies would not only be economical and have fewer side effects, but also help to improve the QOL of cancer patients. Recently, bovine colostrum (BC) has caught the attention of many investigators to explore its anticancer potential in humans. BC impregnated dressings are highly effective in treating chronic wounds and diabetic foot ulcer. BC is rich in lactoferrin, a glycoprotein with strong antioxidant, anti-inflammatory, anti-cancer, and anti-microbial properties. Intravaginal application of BC tablets is effective in causing the regression of low-grade cervical intraepithelial neoplasia. The underlying mechanisms of BC at cellular, genetic, and molecular levels remain to be ascertained. Oral BC supplement is well-tolerated, but some people may experience problems such as flatulence and nausea. Well-designed, randomized, placebo-controlled, clinical trials are needed to access the therapeutic potential, long-term safety, and optimal doses of BC products. This review is aimed to highlight the anticancer potential of BC and its components, and the therapeutic applications of BC supplements in treating gastrointestinal diseases in children and adults. We also discuss the health promotion benefits and therapeutic potential of BC nutraceuticals in reducing the incidence of non-communicable diseases.

Early Effect of Supplemented Infant Formulae on Intestinal Biomarkers and Microbiota: A Randomized Clinical Trial

Background: Post-natal gut maturation in infants interrelates maturation of the morphology, digestive, and immunological functions and gut microbiota development. Here, we explored both microbiota development and markers of gut barrier and maturation in healthy term infants during their early life to assess the interconnection of gut functions during different infant formulae regimes. Methods: A total of 203 infants were enrolled in this randomized double-blind controlled trial including a breastfed reference group. Infants were fed starter formulae for the first four weeks of life, supplemented with different combination of nutrients (lactoferrin, probiotics (Bifidobacterium animal subsp. Lactis) and prebiotics (Bovine Milk-derived Oligosaccharides—BMOS)) and subsequently fed the control formula up to eight weeks of life. Stool microbiota profiles and biomarkers of early gut maturation, calprotectin (primary outcome), elastase, α-1 antitrypsin (AAT) and neopterin were measured in feces at one, two, four, and eight weeks. Results: Infants fed formula containing BMOS had lower mean calprotectin levels over the first two to four weeks compared to the other formula groups. Elastase and AAT levels were closer to levels observed in breastfed infants. No differences were observed for neopterin. Global differences between the bacterial communities of all groups were assessed by constrained multivariate analysis with hypothesis testing. The canonical correspondence analysis (CCA) at genus level showed overlap between microbiota profiles at one and four weeks of age in the BMOS supplemented formula group with the breastfed reference, dominated by bifidobacteria. Microbiota profiles of all groups at four weeks were significantly associated with the calprotectin levels at 4 (CCA, p = 0.018) and eight weeks of age (CCA, p = 0.026). Conclusion: A meaningful correlation was observed between changes in microbiota composition and gut maturation marker calprotectin. The supplementation with BMOS seems to favor gut maturation closer to that of breastfed infants.

Dysregulated Mucosal Immunity and Associated Pathogeneses in Preterm Neonates

Many functions of the immune system are impaired in neonates, allowing vulnerability to serious bacterial, viral and fungal infections which would otherwise not be pathogenic to mature individuals. This vulnerability is exacerbated in compromised newborns such as premature neonates and those who have undergone surgery or who require care in an intensive care unit. Higher susceptibility of preterm neonates to infections is associated with delayed immune system maturation, with deficiencies present in both the innate and adaptive immune components. Here, we review recent insights into early life immunity, and highlight features associated with compromised newborns, given the challenges of studying neonatal immunity in compromised neonates due to the transient nature of this period of life, and logistical and ethical obstacles posed by undertaking studies newborns and infants. Finally, we highlight how the unique immunological characteristics of the premature host play key roles in the pathogenesis of diseases that are unique to this population, including necrotizing enterocolitis and the associated sequalae of lung and brain injury.

Synergistic Killing of Pathogenic Escherichia coli Using Camel Lactoferrin from Different Saudi Camel Clans and Various Antibiotics

Current study aimed to analyze the synergistic killing of pathogenic Escherichia coli using camel lactoferrin from different Saudi camel clans and various antibiotics. Methods: using multiple microbiological and protein analysis techniques, the results were shown that the purified camel lactoferrins (cLfs) from different Saudi camel have strong antimicrobial potentials against two strains of E. coli. Although all cLfs were superior relative to human or bovine lactoferrins (hLf or bLf), there was no noticeable difference in the antimicrobial potentials of cLfs from different camel clans. The effects of antibiotics and cLfs were synergistic, indicating the superiority of using cLf-antibiotic combinations against E. coli growth. Since these combinations possessed distinguished synergy profiles, it is likely that they can be used to enhance the low efficacy of antibiotics, as well as to control the problems associated with bacterial resistance. Furthermore, these combinations can reduce the cost of cure of bacterial infections, especially in the developing countries. The analysis of the molecular mechanisms of lactoferrin action revealed that expression of several E. coli proteins was affected by the treatment with these antibacterial factors. Several proteins of different molecular weights interacting with cLf-biotin were found. Scanning and transmission electron microscopy analysis revealed the presence of noticeable morphological changes associated with the treatment of E. coli strains by antibiotic carbenicillin or cLf alone, and in combination. Camel lactoferrin has superior potential killing of E. coli over bovine and human lactoferrin, and this potential can be further synergistically enhanced of cLF is combined with antibiotics.

Enteral lactoferrin supplementation for prevention of sepsis and necrotizing enterocolitis in preterm infants

BACKGROUND

Lactoferrin, a normal component of human colostrum and milk, can enhance host defenses and may be effective for prevention of sepsis and necrotizing enterocolitis (NEC) in preterm neonates.

OBJECTIVES

To assess the safety and effectiveness of lactoferrin supplementation to enteral feeds for prevention of sepsis and NEC in preterm neonates. Secondarily, we assessed the effects of lactoferrin supplementation to enteral feeds on the duration of positive-pressure ventilation, development of chronic lung disease (CLD) or periventricular leukomalacia (PVL), length of hospital stay to discharge among survivors, and adverse neurological outcomes at two years of age or later.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to update our search. We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2019, Issue 9), MEDLINE via PubMed (1966 to 20 January 2020), PREMEDLINE (1996 to 20 January 2020), Embase (1980 to 20 January 2020), and CINAHL (1982 to 20 January 2020). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomized controlled trials and quasi-randomized trials.

SELECTION CRITERIA

In our search, we included randomized controlled trials (RCTs) evaluating enteral lactoferrin supplementation at any dose or duration to prevent sepsis or NEC in preterm neonates.

DATA COLLECTION AND ANALYSIS

We used the standard methods of Cochrane Neonatal and the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

Meta-analysis of data from twelve randomized controlled trials showed that lactoferrin supplementation to enteral feeds decreased late-onset sepsis (typical RR 0.82, 95% CI 0.74 to 0.91; typical RD -0.04, 95% CI, -0.06, -0.02; NNTB 25, 95% CI 17 to 50; 12 studies, 5425 participants, low-certainty evidence) and decreased length of hospital stay (MD -2.38, 95% CI, -4.67, -0.09; 3 studies, 1079 participants, low-certainty evidence). Sensitivity analysis including only good methodological certainty studies suggested a decrease in late-onset sepsis with enteral lactoferrin supplementation (typical RR 0.87, 95% CI, 0.78, 0.97; typical RD -0.03, 95% CI, -0.05, -0.0; 9 studies, 4702 participants, low-certainty evidence). There were no differences in NEC stage II or III (typical RR 1.10, 95% CI, 0.86, 1.41; typical RD -0.00, 95% CI, -0.02, 0.01; 7 studies, 4874 participants; low-certainty evidence) or 'all-cause mortality' (typical RR 0.90, 95% CI 0.69, 1.17; typical RD -0.00, 95% CI, -0.01, 0.01; 11 studies, 5510 participants; moderate-certainty evidence). One study reported no differences in neurodevelopmental testing by Mullen's or Bayley III at 24 months of age after enteral lactoferrin supplementation (one study, 292 participants, low-certainty evidence). Lactoferrin supplementation to enteral feeds with probiotics decreased late-onset sepsis (RR 0.25, 95% CI 0.14 to 0.46; RD -0.13, 95% CI -0.18 to -0.08; NNTB 8, 95% CI 6 to 13; 3 studies, 564 participants; low-certainty evidence) and NEC stage II or III (RR 0.04, 95% CI 0.00 to 0.62; RD -0.05, 95% CI -0.08 to -0.03; NNTB 20, 95% CI 12.5 to 33.3; 1 study, 496 participants; very low-certainty evidence), but not 'all-cause mortality' (very low-certainty evidence). Lactoferrin supplementation to enteral feeds with or without probiotics had no effect on CLD, duration of mechanical ventilation or threshold retinopathy of prematurity (low-certainty evidence). Investigators reported no adverse effects in the included studies.

AUTHORS' CONCLUSIONS

We found low-certainty evidence from studies of good methodological quality that lactoferrin supplementation of enteral feeds decreases late-onset sepsis but not NEC ≥ stage II or 'all cause mortality' or neurodevelopmental outcomes at 24 months of age in preterm infants without adverse effects. Low- to very low-certainty evidence suggests that lactoferrin supplementation of enteral feeds in combination with probiotics decreases late-onset sepsis and NEC ≥ stage II in preterm infants without adverse effects, however, there were few included studies of poor methodological quality. The presence of publication bias and small studies of poor methodology that may inflate the effect size make recommendations for clinical practice difficult.

Necrotizing enterocolitis: It's not all in the gut

Necrotizing enterocolitis is the leading cause of death due to gastrointestinal disease in preterm neonates, affecting 5–12% of neonates born at a very-low birth weight. Necrotizing enterocolitis can present with a slow and insidious onset, with some neonates displaying early symptoms such as feeding intolerance. Treatment during the early stages includes bowel rest and careful use of antibiotics, but surgery is required if pneumoperitoneum and intestinal perforation occur. Mortality rates among neonates requiring surgery are estimated to be 20–30%, mandating the development of non-invasive and reliable biomarkers to predict necrotizing enterocolitis before the onset of clinical signs. Such biomarkers would allow at-risk neonates to receive maximal preventative therapies such as careful nutritional consideration, probiotics, and increased skin-to-skin care.

Impact statement

Necrotizing enterocolitis (NEC) is a devastating gastrointestinal disease; its high mortality rate mandates the development of non-invasive biomarkers to predict NEC before its onset. This review summarizes the pathogenesis, prevention, unresolved issues, and long-term outcomes of NEC.

A multisite, randomized field trial to evaluate the influence of lactoferrin on the morbidity and mortality of dairy calves with diarrhea

Diarrhea is one of the most common causes of antimicrobial use and mortality in young calves. To reduce antimicrobial use and resistance on dairy farms, research on alternative therapies for calf diarrhea is necessary. Our laboratory previously conducted a randomized clinical trial investigating the effectiveness of lactoferrin, an iron-binding protein found in colostrum, as a treatment for calf diarrhea. The trial showed significantly reduced calf mortality in diarrheic calves that were administered lactoferrin. Thus, the objective of this study was to corroborate the results of our prior clinical trial across multiple farms and to investigate the effect of lactoferrin on the morbidity and mortality of preweaned calves with naturally occurring cases of diarrhea. This randomized field trial was conducted on 5 commercial dairy farms in Ohio. In total, 485 calves (≤21 d of age) were enrolled at first diarrhea diagnosis (fecal score ≥2 defined as loose to watery) and randomly assigned to receive an oral dose of lactoferrin (3 g of lactoferrin powder dissolved in 30 mL of water) or 30 mL of water (control) once daily for 3 consecutive days. Health assessments were conducted on the day of diarrhea diagnosis (d 0) and 1, 2, 3, 7, 14, 21, 28, and 35 d following diagnosis. Producer records of disease treatment and mortality were collected 120 d following diagnosis. A Poisson regression model was used to test differences between treatments in disease frequency through 35 d post-diarrhea diagnosis and the incidence risk of treatment and mortality risk 120 d post-diarrhea diagnosis; the model controlled for calf age at enrollment, farm, and treatment. Median calf age at enrollment was 11 d and ranged from 1 to 26 d of age. At study enrollment, 51.3% (123/240) and 52.2% (128/245) of calves in the control and lactoferrin treatment groups, respectively, were diagnosed with severe diarrhea (fecal score = 3). The frequency of disease (diarrhea, dehydration, depression, signs of respiratory disease) through 35 d following diarrhea diagnosis was not significantly different for calves in the lactoferrin and control groups. Overall mortality risk for enrolled calves was 9.9%, and 10.7% (22/243) and 9.1% (26/242) of calves in the lactoferrin and control groups, respectively, died or were culled in the 120 d following diarrhea diagnosis. The relative risk of death or culling did not differ between treatment groups, however. Therefore, as performed in this study, lactoferrin as a treatment for calf diarrhea was not beneficial.

The synovial fluid proteome differentiates between septic and nonseptic articular pathologies

Articular conditions are common in horses and can result in loss of function, chronic pain and/or inability to work. Common conditions include osteoarthritis, osteochondrosis and synovial sepsis, which can be life-threatening, but despite the high clinical prevalence of these conditions, rapid and specific diagnosis, monitoring and prognostication remains a challenge for practicing veterinarians. Synovial fluid from a range of arthropathies was enriched for low abundance proteins using combinatorial peptide ligand ProteoMiner™ beads and analysed via liquid chromatography-tandem mass spectrometry. Changes in protein abundances were analysed using label-free quantification. Principle component analysis of differentially expressed proteins identified groupings associated with joint pathology. Findings were validated using ELISA. Lactotransferrin (LTF) abundance was increased in sepsis compared to all other groups and insulin-like growth factor-binding protein 6 (IGFBP6) abundance decreased in sepsis compared to other disease groups. Pathway analysis identified upregulation of the complement system in synovial joint sepsis and the downregulation of eukaryotic translation initiation factors and mTOR signalling pathways in both OA and OC compared to the healthy group. Overall, we have identified a catalogue of proteins which we propose to be involved in osteoarthritis, osteochondrosis and synovial sepsis pathogenesis. SIGNIFICANCE: Osteoarthritis, osteochondrosis and synovial sepsis, which can be life-threatening, are common articular conditions in which rapid and specific diagnosis, monitoring and prognostication remains a challenge for practicing veterinarians. This study has identified that the equine synovial fluid proteome exhibits distinctive profile changes between osteoarthritis, osteochondrosis, synovial sepsis and healthy joints. Elevated synovial abundance of lactotransferrin and decreased insulin-like growth factor-binding protein 6 were both found to distinguish synovial sepsis from all other study groups. Thus, these protein markers may have a future role in clinical practice to enable an earlier and reliable diagnosis of synovial sepsis.

Enteral lactoferrin to prevent infection for very preterm infants: the ELFIN RCT

BACKGROUND

Infections acquired in hospital are an important cause of morbidity and mortality in very preterm infants. Several small trials have suggested that supplementing the enteral diet of very preterm infants with lactoferrin, an antimicrobial protein processed from cow's milk, prevents infections and associated complications.

OBJECTIVE

To determine whether or not enteral supplementation with bovine lactoferrin (The Tatua Cooperative Dairy Company Ltd, Morrinsville, New Zealand) reduces the risk of late-onset infection (acquired > 72 hours after birth) and other morbidity and mortality in very preterm infants.

DESIGN

Randomised, placebo-controlled, parallel-group trial. Randomisation was via a web-based portal and used an algorithm that minimised for recruitment site, weeks of gestation, sex and single versus multiple births.

SETTING

UK neonatal units between May 2014 and September 2017.

PARTICIPANTS

Infants born at < 32 weeks' gestation and aged < 72 hours at trial enrolment.

INTERVENTIONS

Eligible infants were allocated individually (1 : 1 ratio) to receive enteral bovine lactoferrin (150 mg/kg/day; maximum 300 mg/day) or sucrose (British Sugar, Peterborough, UK) placebo (same dose) once daily from trial entry until a postmenstrual age of 34 weeks. Parents, caregivers and outcome assessors were unaware of group assignment.

OUTCOMES

Primary outcome - microbiologically confirmed or clinically suspected late-onset infection. Secondary outcomes - microbiologically confirmed infection; all-cause mortality; severe necrotising enterocolitis (NEC); retinopathy of prematurity (ROP); bronchopulmonary dysplasia (BPD); a composite of infection, NEC, ROP, BPD and mortality; days of receipt of antimicrobials until 34 weeks' postmenstrual age; length of stay in hospital; and length of stay in intensive care, high-dependency and special-care settings.

RESULTS

Of 2203 enrolled infants, primary outcome data were available for 2182 infants (99%). In the intervention group, 316 out of 1093 (28.9%) infants acquired a late-onset infection versus 334 out of 1089 (30.7%) infants in the control group [adjusted risk ratio (RR) 0.95, 95% confidence interval (CI) 0.86 to 1.04]. There were no significant differences in any secondary outcomes: microbiologically confirmed infection (RR 1.05, 99% CI 0.87 to 1.26), mortality (RR 1.05, 99% CI 0.66 to 1.68), NEC (RR 1.13, 99% CI 0.68 to 1.89), ROP (RR 0.89, 99% CI 0.62 to 1.28), BPD (RR 1.01, 99% CI 0.90 to 1.13), or a composite of infection, NEC, ROP, BPD and mortality (RR 1.01, 99% CI 0.94 to 1.08). There were no differences in the number of days of receipt of antimicrobials, length of stay in hospital, or length of stay in intensive care, high-dependency or special-care settings. There were 16 reports of serious adverse events for infants in the lactoferrin group and 10 for infants in the sucrose group.

CONCLUSIONS

Enteral supplementation with bovine lactoferrin does not reduce the incidence of infection, mortality or other morbidity in very preterm infants.

FUTURE WORK

Increase the precision of the estimates of effect on rarer secondary outcomes by combining the data in a meta-analysis with data from other trials. A mechanistic study is being conducted in a subgroup of trial participants to explore whether or not lactoferrin supplementation affects the intestinal microbiome and metabolite profile of very preterm infants.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN88261002.

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. 22, No. 74. See the NIHR Journals Library website for further project information. This trial was also sponsored by the University of Oxford, Oxford, UK. The funder provided advice and support and monitored study progress but did not have a role in study design or data collection, analysis and interpretation.

Neuroprotective Care of Extremely Preterm Infants in the First 72 Hours After Birth

Birth at extremely low gestational ages presents a significant threat to infants' survival, health, development, and future well-being. After birth, a critical period of brain development must continue outside the womb. Neuro-supportive and neuroprotective family centered developmental care for and standardized care practices for extremely preterm infants have been shown to improve outcomes. Neuroprotective interventions must include a focus on the emotional connections of infants and their families. Being in skin-to-skin contact with the mother is the developmentally expected environment for all mammals and is especially important for supporting physiologic stability and neurodevelopment of preterm infants.

Enteral feeding composition and necrotizing enterocolitis

Enteral feeding and composition play a chief role in the prevention and treatment of necrotizing enterocolitis (NEC). In the face of decades of research on this fatal disease, the exact mechanism of disease is still poorly understood. There is established evidence that providing mother's own breast milk and standardization of feeding regimens leads to a decreased risk for NEC. More recent studies have focused on the provision of donor human milk or an exclusive human milk diet in the endeavor to prevent NEC while still maintaining adequate nutrition to the premature infant. There is growing literature on the provision of specific human milk components and its effect on the incidence of NEC.

Bovine Lactoferrin Enhances TLR7-Mediated Responses in Plasmacytoid Dendritic Cells in Elderly Women: Results From a Nutritional Intervention Study With Bovine Lactoferrin, GOS and Vitamin D

During aging the immune system is dysregulated. Especially plasmacytoid dendritic cells (pDCs) and myeloid DCs (mDCs) have reduced Toll like receptor (TLR)-mediated responses resulting in increased susceptibility to infections. Consumption of bovine lactoferrin (bLF) has been shown to reduce infections with viruses. Galacto-oligosacharides (GOS) and vitamin D are associated with reduced pro-inflammatory cytokine levels in serum, and increased TLR7/8 responses, respectively. A double-blind placebo-controlled nutritional intervention study in elderly women was performed, to investigate the potential of bLF, GOS, and vitamin D to restore TLR responsiveness of pDCs and mDCs and to reduce inflammatory markers in serum. The nutritional intervention group (n = 15) received bLF for 3 weeks, followed by 3 weeks of bLF + GOS, and subsequently 3 weeks of bLF + GOS + vitamin D. The placebo group (n = 15) received maltodextrin for 9 weeks. Every 3 weeks, blood was collected and TLR responses of pDCs and mDCs, and inflammation-related markers in serum were measured. After 3 weeks of bLF supplementation, increased TLR7/8 and TLR1/2 responses were observed in pDCs of the nutritional intervention group compared to the placebo group. When the effects of the entire nutritional intervention were investigated, increased TLR1/2 mediated responses in mDCs were observed, and in serum sVCAM tended to decrease. Finally, based on the RAND-36 questionnaire physical function tended to improve in the intervention group. Since especially TLR7-mediated responses in pDCs were enhanced after bLF supplementation compared to placebo, this suggests that bLF may contribute to antiviral responses mediated by pDC in elderly women.Clinical trial registry number: NCT03026244, clinicaltrials.gov:

Sepsis and Oxidative Stress in the Newborn: From Pathogenesis to Novel Therapeutic Targets

Sepsis is at present one of the leading causes of morbidity and mortality in the neonatal population. Together with inflammation, oxidative stress is involved in detrimental pathways activated during neonatal sepsis, eventually leading to organ dysfunction and death. The redox cascade during sepsis is mainly initiated by IL-6 and IL-8 stimulation in newborns and includes multiple noxious processes, as direct cell damage induced by reactive oxygen species, activation of gene expression leading to amplification of inflammation and oxidative stress, and impairment of mitochondrial function. Once proinflammatory and prooxidant pathways are established as stimulated by causing pathogens, self-maintaining unfavorable redox cycles ensue, leading to oxidative stress-related cellular damage, independently from the activating pathogens themselves. Despite antioxidant systems are induced during neonatal sepsis, as an adaptive response to an increased oxidative burden, a condition of redox imbalance favoring oxidative pathways occurs, resulting in increased markers of oxidative stress damage. Therefore, antioxidant treatment would exert beneficial effects during neonatal sepsis, potentially interrupting prooxidant pathways and preventing the maintenance of detrimental redox cycles that cannot be directly affected by antibiotic treatment. Among others, antioxidant agents investigated in clinical settings as adjunct treatment for neonatal sepsis include melatonin and pentoxifylline, both showing promising results, while novel antioxidant molecules, as edaravone and endothelin receptor antagonists, are at present under investigation in animal models. Finally, mitochondria-targeted antioxidant treatments could represent an interesting line of research in the treatment of neonatal sepsis.

Immunomodulation to Prevent or Treat Neonatal Sepsis: Past, Present, and Future

Despite continued advances in neonatal medicine, sepsis remains a leading cause of death worldwide in neonatal intensive care units. The clinical presentation of sepsis in neonates varies markedly from that in older children and adults, and distinct acute inflammatory responses results in age-specific inflammatory and protective immune response to infection. This review first provides an overview of the neonatal immune system, then covers current mainstream, and experimental preventive and adjuvant therapies in neonatal sepsis. We also discuss how the distinct physiology of the perinatal period shapes early life immune responses and review strategies to reduce neonatal sepsis-related morbidity and mortality. A summary of studies that characterize immune ontogeny and neonatal sepsis is presented, followed by discussion of clinical trials assessing interventions such as breast milk, lactoferrin, probiotics, and pentoxifylline. Finally, we critically appraise future treatment options such as stem cell therapy, other antimicrobial protein and peptides, and targeting of pattern recognition receptors in an effort to prevent and/or treat sepsis in this highly vulnerable neonatal population.

Clinical Outcomes Related to the Gastrointestinal Trophic Effects of Erythropoietin in Preterm Neonates: A Systematic Review and Meta-Analysis

Erythropoietin (EPO) plays an important role in the development and maturation of the gastrointestinal tract. Recombinant EPO (rEPO) has been used to prevent anemia of prematurity. The gastrointestinal trophic effects of EPO may reduce feeding intolerance and necrotizing enterocolitis (NEC) in preterm neonates. The aim of this systematic review of randomized controlled trials (RCTs) was to evaluate the effects of rEPO on clinical outcomes such as feeding intolerance, stage II or higher NEC, any stage NEC, sepsis, retinopathy of prematurity, and bronchopulmonary dysplasia in preterm neonates. Twenty-five RCTs (intravenous: 13; subcutaneous: 10; enteral: 2; n = 4025) were eligible for inclusion. Meta-analysis of data from 17 RCTs (rEPO compared with placebo) with the use of a fixed-effects model showed no significant effect of rEPO on stage II or higher NEC (RR: 0.87; 95% CI: 0.64, 1.19; P = 0.39). Meta-analysis of data from 25 RCTs (rEPO compared with placebo) showed that rEPO significantly decreased the risk of any stage NEC [cases/total sample: 120/2058 (5.83%) compared with 146/1967 (7.42%); RR: 0.77; 95% CI: 0.61, 0.97; P = 0.03]. Only one RCT reported on time to full feedings. Meta-analysis of data from 15 RCTs showed a significant reduction in late-onset sepsis after rEPO administration (RR: 0.81; 95% CI: 0.71, 0.94; P = 0.004). Meta-analysis of 13 RCTs showed no significant effect of rEPO on mortality, retinopathy of prematurity, and bronchopulmonary dysplasia. Prophylactic rEPO had no effect on stage II or higher NEC, but it reduced any stage NEC, probably by reducing feeding intolerance, which is often labeled as stage I NEC. Adequately powered RCTs are required to confirm these findings.

Toll-Like Receptor-Mediated Intestinal Inflammatory Imbalance in the Pathogenesis of Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) remains the leading cause of death from gastrointestinal disease in premature infants and attacks the most fragile patients at a time when they appear to be the most stable. Despite significant advances in our overall care of the premature infant, NEC mortality remains stubbornly high. There is no specific treatment for NEC beyond broad-spectrum antibiotics and intestinal resection, and current efforts have focused on preventive strategies. Over the past decade, we have proposed a unifying hypothesis to explain the pathogenesis of NEC in premature infants that suggests that NEC develops in response to an imbalance between exaggerated proinflammatory signaling in the mucosa of the premature gut leading to mucosal injury, which is not countered effectively by endogenous repair processes, and in the setting of impaired mesenteric perfusion leads to intestinal ischemia and disease development. One of the most important pathways that mediates the balance between injury and repair in the premature intestine, and that plays a key role in NEC pathogenesis, is Toll-like receptor 4 (TLR4), which recognizes lipopolysaccharide on gram-negative bacteria. This review focuses on the role that the TLR4-mediated imbalance between proinflammatory and anti-inflammatory signaling in the premature intestinal epithelium leads to the development of NEC, and will explore how an understanding of the role of TLR4 in NEC pathogenesis has led to the identification of novel preventive or treatment approaches for this devastating disease.

Human lactoferrin attenuates the proinflammatory response of neonatal monocyte-derived macrophages

Bioactive components of human milk, such as human lactoferrin (hLF), play an essential role in gut microbiome homeostasis and protection against neonatal inflammatory diseases. Neonatal intestinal macrophages display a proinflammatory profile that might contribute to inflammatory mucosal injury. Therefore, the aim of the study was to investigate the immunomodulatory effects of hLF on differentiation and activation of monocyte‐derived macrophages (moMϕ). Monocytes isolated from umbilical cord blood of term neonates and peripheral blood of healthy adults were differentiated in the absence or presence of hLF, and differentiation, apoptosis and phagocytosis were evaluated. Cytokine production, Toll‐like receptor (TLR) signalling and activation marker expression were investigated upon activation with lipopolysaccharide (LPS) and lipoteichoic acid (LTA) challenge. We demonstrate that hLF‐differentiated moMϕ exhibit decreased TLR‐4 expression, TLR signalling, proinflammatory cytokine secretion and intracellular tumour necrosis factor (TNF)‐α production. Investigation of differentiation markers, morphology and induction of apoptosis showed no alteration in lactoferrin‐differentiated moMϕ. Taken together, hLF promote anergic/anti‐inflammatory effects by TLR expression and pathway interference, resulting in a diminished proinflammatory moMϕ phenotype. The anergic/anti‐inflammatory properties of hLF might contribute to the prevention of harmful TLR‐mediated inflammatory disorders in the developing gut of premature infants.

A Mixed Lipid Emulsion for Prevention of Parenteral Nutrition Associated Cholestasis in Extremely Low Birth Weight Infants: A Randomized Clinical Trial

OBJECTIVES

To examine whether a mixed lipid emulsion reduces the incidence of parenteral nutrition associated cholestasis (PNAC) in extremely low birth weight (ELBW, <1000 g) infants.

STUDY DESIGN

This double-blind randomized trial of 230 ELBW infants (June 2012-October 2015) was performed at a single level IV neonatal intensive care unit. Patients received either a mixed lipid emulsion composed of soybean oil, medium chain triglycerides, olive oil, and fish oil-(intervention) or a soybean oil-based lipid emulsion (control) for parenteral nutrition. The primary outcome measure was PNAC (conjugated bilirubin >1.5 mg/dL [25 µmol/L] at 2 consecutive measurements). The study was powered to detect a reduction of PNAC from 25% to 10%.

RESULTS

Reasons for noneligibility of 274 infants screened were refusal to participate (n = 16), death (n = 10), withdrawal of treatment (n = 5), higher order multiples (n = 9), and parents not available for consent (n = 4). Intention to treat analysis was carried out in 223 infants (7 infants excluded after randomization). Parenteral nutrition associated cholestasis was 11 of 110 (10.1%) in the intervention and 18 of 113 (15.9%) in the control group (P = .20). Multivariable analyses showed no statistically significant difference in the intention to treat (aOR 0.428, 95% CI 0.155-1.187; P = .10) or per protocol population (aOR 0.457, 95% CI 0.155-1.347; P = .16). There was no statistically significant effect on any other neonatal morbidity.

CONCLUSIONS

The incidence of parenteral nutrition associated cholestasis was not significantly reduced using a mixed lipid emulsion in ELBW infants.

TRIAL REGISTRATION

ClinicalTrials.govNCT01585935.

Exposure to Gastric Acid Inhibitors Increases the Risk of Infection in Preterm Very Low Birth Weight Infants but Concomitant Administration of Lactoferrin Counteracts This Effect

OBJECTIVE

To investigate whether exposure to inhibitors of gastric acidity, such as H2 blockers or proton pump inhibitors, can independently increase the risk of infections in very low birth weight (VLBW) preterm infants in the neonatal intensive care unit.

STUDY DESIGN

This is a secondary analysis of prospectively collected data from a multicenter, randomized controlled trial of bovine lactoferrin (BLF) supplementation (with or without the probiotic Lactobacillus rhamnosus GG) vs placebo in prevention of late-onset sepsis (LOS) and necrotizing enterocolitis (NEC) in preterm infants. Inhibitors of gastric acidity were used at the recommended dosages/schedules based on the clinical judgment of attending physicians. The distribution of days of inhibitors of gastric acidity exposure between infants with and without LOS/NEC was assessed. The mutually adjusted effects of birth weight, gestational age, duration of inhibitors of gastric acidity treatment, and exposure to BLF were controlled through multivariable logistic regression. Interaction between inhibitors of gastric acidity and BLF was tested; the effects of any day of inhibitors of gastric acidity exposure were then computed for BLF-treated vs -untreated infants.

RESULTS

Two hundred thirty-five of 743 infants underwent treatment with inhibitors of gastric acidity, and 86 LOS episodes occurred. After multivariate analysis, exposure to inhibitors of gastric acidity remained significantly and independently associated with LOS (OR, 1.03; 95% CI, 1.008-1.067; P = .01); each day of inhibitors of gastric acidity exposure conferred an additional 3.7% odds of developing LOS. Risk was significant for Gram-negative (P < .001) and fungal (P = .001) pathogens, but not for Gram-positive pathogens (P = .97). On the test for interaction, 1 additional day of exposure to inhibitors of gastric acidity conferred an additional 7.7% risk for LOS (P = .003) in BLF-untreated infants, compared with 1.2% (P = .58) in BLF-treated infants.

CONCLUSION

Exposure to inhibitors of gastric acidity is significantly associated with the occurrence of LOS in preterm VLBW infants. Concomitant administration of BLF counteracts this selective disadvantage.

TRIAL REGISTRATION

isrctn.org: ISRCTN53107700.

Reduction in necrotizing enterocolitis and improved outcomes in preterm infants following routine supplementation with Lactobacillus GG in combination with bovine lactoferrin

BACKGROUND

Preterm infants remain at high risk of adverse outcomes following necrotizing enterocolitis (NEC) and late onset sepsis (LOS). Meta-analysis of randomized trials has indicated a reduction in severe NEC following use of probiotics and bovine lactoferrin (LF). Overall, however, uncertainty remains over which probiotic, or combination to use. The aim of this study was to compare the incidence of severe NEC and LOS before and after routine supplementation with Lactobacillus GG (LGG) and LF.

METHODS

In this retrospective cohort study, infants <32 weeks or <1500 g routinely received LGG and 100 mg lactoferrin daily from 2011 -2015 were compared with similar infants born from 2004-2008. Cases of NEC were Bell stage 2 or greater and LOS was blood or spinal fluid culture positive after 48 hrs of age.

RESULTS

We noted a marked decline in the incidence of NEC from 3% to 1% with a RR of 0.29 (CI 0.1-0.9) and a number needed to benefit of 50. The cost of preventing one case of NEC was estimated to be NZ $2800, considerably lower than the cost of treatment. LOS rates were not significantly different. There was a decrease in retinopathy treatment rates. During the period there was one case of LGG sepsis in a 23 week gestation infant with abdominal pathology and one infant developed NEC after stopping prophylaxis.

CONCLUSION

The rates of severe NEC was markedly reduced following prophylaxis. The case of LGG sepsis indicates caution is required in extremely preterm infants.

Impact and Time Course of Clostridium difficile Colonization in Very Low Birth Weight Infants

BACKGROUND

Clostridium difficile is a gram-positive, anaerobic spore-forming, toxin-producing bacillus, which is one of the most common causes for health care-associated infections. High colonization rates in clinically asymptomatic neonates and infants have been described, although most studies go back to the early 1980 and 1990s, and were carried out in term and late preterm infants.

OBJECTIVES

The aim of our study was to determine both the impact and time course of C. difficile colonization in a cohort of very low birth weight infants (VLBWI) in an era of PCR-based technologies for diagnosis.

METHODS

Stool samples of VLBWI were analyzed for the presence of C. difficile strains in regular intervals during the hospital stay by PCR ribotyping. Analysis was continued throughout the first 2 years of life.

RESULTS

A 32% C. difficile colonization rate during the first 2 years of life and an in-hospital colonization rate of 8% was found in a cohort of 190 VLBWI. C. difficile colonization occurred mainly in the first 6 months of life, which was similar to term neonates. In-hospital colonization accounted for only a small percentage of cases with no detection of hypervirulent strains. Also, C. difficile colonization was not related to an adverse outcome in this VLBWI cohort. Oral lactoferrin of bovine origin and treatment with piperacillin/tazobactam were negatively correlated with C. difficile colonization in our study.

CONCLUSIONS

C. difficile colonization in our cohort of VLBWI was significantly lower than has been described in the literature and was not related to an adverse outcome.

Necrotizing enterocolitis and high intestinal iron uptake due to genetic variants

BackgroundIntestinal iron is a nutritional compound, which is essential for enteric microbiota. We evaluated the hypothesis that polymorphisms, which are known modifiers of intestinal iron uptake in adults, are associated with necrotizing enterocolitis (NEC) in preterm infants.MethodsPreterm infants (birth weight below 1,500 g) were studied. Single-nucleotide polymorphisms with known effects on serum iron levels (rs1800562, rs1799945, and rs855791) were determined using PCR. The effects of polymorphisms on NEC surgery were tested by Mendelian randomization. Outcome data were compared with χ²-test, Fisher's exact test, t-test, and Cochran-Armitage test for trend and multiple logistic regression analysis.ResultsComplete genotyping data were available for 11,166 infants. High serum iron levels due to rs855791 genotype were associated with a significantly reduced risk of NEC surgery (odds ratio (OR) 0.265; 95% confidence interval (CI) 0.11-0.65; adjusted P=0.011). Carriers of the rs855791 A-allele not receiving prophylactic probiotics had a higher risk of NEC surgery (OR 1.12, 95% CI 1.08-1.70, nominal P=0.002). Prophylactic treatment with probiotics was associated with a reduced risk of NEC surgery in carriers of the rs855791 A-Allele. No differences were found with regard to other short- or long-term outcome data.ConclusionPolymorphisms inducing lower intestinal iron uptake like the rs855791 A-allele might be an underestimated risk factor for NEC.

Late-onset Sepsis in Extremely Premature Infants: 2000-2011

BACKGROUND

Late-onset sepsis (LOS) is an important cause of death and neurodevelopmental impairment in premature infants. The purpose of this study was to assess overall incidence of LOS, distribution of LOS-causative organisms and center variation in incidence of LOS for extremely premature infants over time.

METHODS

In a retrospective analysis of infants 401-1000 g birth weight and 22-28 6/7 weeks of gestational age born at 12 National Institute of Child Health and Human Development Neonatal Research Network centers in the years 2000-2005 (era 1) or 2006-2011 (era 2) who survived >72 hours, we compared the incidence of LOS and pathogen distribution in the 2 eras using the χ test. We also examined the effect of birth year on the incidence of LOS using multivariable regression to adjust for nonmodifiable risk factors and for center. To assess whether the incidence of LOS was different among centers in era 2, we used a multivariable regression model to adjust for nonmodifiable risk factors.

RESULTS

Ten-thousand one-hundred thirty-one infants were studied. LOS occurred in 2083 of 5031 (41%) infants in era 1 and 1728 of 5100 (34%) infants in era 2 (P < 0.001). Birth year was a significant predictor of LOS on adjusted analysis, with birth years 2000-2009 having a significantly higher odds of LOS than the reference year 2011. Pathogens did not differ, with the exception of decreased fungal infection (P < 0.001). In era 2, 9 centers had significantly higher odds of LOS compared with the center with the lowest incidence.

CONCLUSIONS

The incidence of LOS decreased over time. Further investigation is warranted to determine which interventions have the greatest impact on infection rates.

Benefits of Lactoferrin, Osteopontin and Milk Fat Globule Membranes for Infants

The provision of essential and non-essential amino acids for breast-fed infants is the major function of milk proteins. In addition, breast-fed infants might benefit from bioactivities of milk proteins, which are exhibited in the intestine during the digestive phase and by absorption of intact proteins or derived peptides. For lactoferrin, osteopontin and milk fat globule membrane proteins/lipids, which have not until recently been included in substantial amounts in infant formulas, in vitro experiments and animal models provide a convincing base of evidence for bioactivities, which contribute to the protection of the infant from pathogens, improve nutrient absorption, support the development of the immune system and provide components for optimal neurodevelopment. Technologies have become available to obtain these compounds from cow´s milk and the bovine compounds also exhibit bioactivities in humans. Randomized clinical trials with experimental infant formulas incorporating lactoferrin, osteopontin, or milk fat globule membranes have already provided some evidence for clinical benefits. This review aims to compare findings from laboratory and animal experiments with outcomes of clinical studies. There is good justification from basic science and there are promising results from clinical studies for beneficial effects of lactoferrin, osteopontin and the milk fat globule membrane complex of proteins and lipids. Further studies should ideally be adequately powered to investigate effects on clinically relevant endpoints in healthy term infants.

Probiotics and gastrointestinal conditions: An overview of evidence from the Cochrane Collaboration

Alterations in the composition of the gut microbiota are associated with a number of gastrointestinal (GI) conditions, including diarrhea, inflammatory bowel diseases (IBD), and liver diseases. Probiotics, live microorganisms that may confer a health benefit to the host when consumed, are commonly used as a therapy for treating these GI conditions by means of modifying the composition or activity of the microbiota. The purpose of this review was to summarize the evidence on probiotics and GI conditions available from Cochrane, a nonprofit organization that produces rigorous and high-quality systematic reviews of health interventions. Findings from this review will help provide more precise guidance for clinical use of probiotics and to identify gaps in probiotic research related to GI conditions.

Standardized feeding regimen for reducing necrotizing enterocolitis in preterm infants: an updated systematic review

OBJECTIVE

A systematic review (2005) of observational studies has reported 87% reduction in the incidence of necrotizing enterocolitis (NEC) after introducing standardized feeding regimen (SFR) in preterm infants. Considering the many new studies in this field since 2005 and the continued health burden of NEC, we aimed to systematically review the incidence of NEC in preterm infants 'before' vs 'after' implementing a SFR.

STUDY DESIGN

PubMed, EMBASE, CINAHL and E-abstracts from the Pediatric Academic Society meetings and other pediatric and neonatal conference proceedings were searched in May 2016. Observational studies reporting incidence of NEC before and after implementing a SFR were included. Relevant data were extracted independently by two reviewers. Meta-analysis was conducted using random effects model (REM) and results rechecked with fixed effects model.

RESULTS

Pooled results from 15 observational studies (N=18 160) using REM showed that SFR significantly reduced the incidence of NEC (risk ratio 0.22; 95% confidence interval 0.13 to 0.36; P<0.00001; I2=74%). The results remained significant after comparing studies in two epochs (1978 to 2003 vs 2004 to 2016).

CONCLUSION

SFR continues to be an important tool in prevention of NEC in preterm infants.

Enteral lactoferrin supplementation for prevention of sepsis and necrotizing enterocolitis in preterm infants

BACKGROUND

Lactoferrin, a normal component of human colostrum and milk, can enhance host defenses and may be effective for prevention of sepsis and necrotizing enterocolitis (NEC) in preterm neonates.

OBJECTIVES

Primary objective 1. To assess the safety and effectiveness of lactoferrin supplementation to enteral feeds for prevention of sepsis and NEC in preterm neonates Secondary objectives 1. To determine the effects of lactoferrin supplementation to enteral feeds to prevent neonatal sepsis and/or NEC on duration of positive-pressure ventilation, development of chronic lung disease (CLD) or periventricular leukomalacia (PVL), length of hospital stay to discharge among survivors, and adverse neurological outcomes at two years of age or later2. To determine the adverse effects of lactoferrin supplementation for prophylaxis of neonatal sepsis and/or NECWhen data were available, we analyzed the following subgroups.1. Gestational age < 32 weeks and 32 to 36 weeks2. Birth weight < 1000 g (extremely low birth weight (ELBW) infants) and birth weight < 1500 g (very low birth weight (VLBW) infants)3. Type of feeding: breast milk versus formula milk SEARCH METHODS: We used the search strategy of the Cochrane Neonatal Review Group (CNRG) to update our search in December 2016. We searched the databases Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PREMEDLINE, Embase, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL), as well as trial registries and conference proceedings.

SELECTION CRITERIA

Randomized controlled trials (RCTs) evaluating oral lactoferrin at any dose or duration to prevent sepsis or NEC in preterm neonates.

DATA COLLECTION AND ANALYSIS

Review authors used standard methods of the CNRG.

MAIN RESULTS

This review includes six RCTs. Trial results show that lactoferrin supplementation to enteral feeds decreased late-onset sepsis (typical risk ratio (RR) 0.59, 95% confidence interval (CI) 0.40 to 0.87; typical risk difference (RD) -0.06, 95% CI -0.10 to -0.02; number needed to treat for an additional beneficial outcome (NNTB) 17, 95% CI 10 to 50; six trials, 886 participants; low-quality evidence) and NEC stage II or III (typical RR 0.40, 95% CI 0.18 to 0.86; typical RD -0.04, 95% CI -0.06 to -0.01; NNTB 25, 95% CI 17 to 100; four studies, 750 participants; low-quality evidence). Lactoferrin supplementation did not have an effect on "all-cause mortality" (typical RR 0.65, 95% CI 0.37 to 1.11; typical RD -0.02, 95% CI -0.05 to 0; six studies, 1041 participants; low-quality evidence).Lactoferrin supplementation to enteral feeds with probiotics decreased late-onset sepsis (RR 0.27, 95% CI 0.12 to 0.60; RD -0.13, 95% CI -0.19 to -0.06; NNTB 8, 95% CI 5 to 17; one study, 321 participants; low-quality evidence) and NEC stage II or III (RR 0.04, 95% CI 0.00 to 0.62; RD -0.05, 95% CI -0.08 to -0.03; NNTB 20, 95% CI 12.5 to 33.3; one study, 496 participants; low-quality evidence), but not "all-cause mortality" (low-quality evidence).Lactoferrin supplementation to enteral feeds with or without probiotics decreased bacterial and fungal sepsis but not CLD or length of hospital stay (low-quality evidence). Investigators reported no adverse effects and did not evaluate long-term neurological outcomes and PVL.

AUTHORS' CONCLUSIONS

Evidence of low quality suggests that lactoferrin supplementation to enteral feeds with or without probiotics decreases late-onset sepsis and NEC stage II or III in preterm infants without adverse effects. Completed ongoing trials will provide data from more than 6000 preterm neonates, which may enhance the quality of the evidence. Clarification regarding optimal dosing regimens, types of lactoferrin (human or bovine), and long-term outcomes is needed.

Mechanisms Affecting the Gut of Preterm Infants in Enteral Feeding Trials

Large randomized controlled trials (RCTs) in preterm infants offer unique opportunities for mechanistic evaluation of the risk factors leading to serious diseases, as well as the actions of interventions designed to prevent them. Necrotizing enterocolitis (NEC) a serious inflammatory gut condition and late-onset sepsis (LOS) are common feeding and nutrition-related problems that may cause death or serious long-term morbidity and are key outcomes in two current UK National Institutes for Health Research (NIHR) trials. Speed of increasing milk feeds trial (SIFT) randomized preterm infants to different rates of increases in milk feeds with a primary outcome of survival without disability at 2 years corrected age. Enteral lactoferrin in neonates (ELFIN) randomizes infants to supplemental enteral lactoferrin or placebo with a primary outcome of LOS. This is a protocol for the mechanisms affecting the gut of preterm infants in enteral feeding trials (MAGPIE) study and is funded by the UK NIHR Efficacy and Mechanistic Evaluation programme. MAGPIE will recruit ~480 preterm infants who were enrolled in SIFT or ELFIN. Participation in MAGPIE does not change the main trial protocols and uses non-invasive sampling of stool and urine, along with any residual resected gut tissue if infants required surgery. Trial interventions may involve effects on gut microbes, metabolites (e.g., short-chain fatty acids), and aspects of host immune function. Current hypotheses suggest that NEC and/or LOS are due to a dysregulated immune system in the context of gut dysbiosis, but mechanisms have not been systematically studied within large RCTs. Microbiomic analysis will use next-generation sequencing, and metabolites will be assessed by mass spectrometry to detect volatile organic and other compounds produced by microbes or the host. We will explore differences between disease cases and controls, as well as exploring the actions of trial interventions. Impacts of this research are multiple: translation of knowledge of mechanisms promoting gut health may explain outcomes or suggest alternate strategies to improve health. Results may identify new non-invasive diagnostic or monitoring techniques, preventative or treatment strategies for NEC or LOS, or provide data useful for risk stratification in future studies. Mechanistic evaluation might be especially informative where there are not clear effects on the primary outcome (ISRCTN 12554594).

Lactoferrin concentration in breast milk of mothers of low-birth-weight newborns

OBJECTIVES

Lactoferrin (LF) is a breast milk glycoprotein with protective effects against neonatal infections, mainly in premature and low-birth-weight (LBW) neonates. The aims of this study were to determine LF concentration in breast milk of mothers of LBW infants during the first 2 months postpartum, and to identify the factors associated with LF concentration.

STUDY DESIGN

Prospective study conducted as a part of an ongoing clinical trial in three Neonatal Units in Peru. We included 346 mothers of neonates with a birth weight <2000 g. We measured LF concentration in four stages of lactation using a commercial enzyme-linked immunosorbent assay kit. Multivariate analysis was performed to assess the association between maternal and neonatal factors, and LF concentration.

RESULTS

We collected 695 milk samples. LF mean concentration±standard deviation was 14.92±7.96 mg ml^-1 in colostrum (n=277), 10.73±5.67 in transitional milk (n=55), 10.34±6.27 at 1 month (n=259) and 8.52±6.47 at 2 months (n=104). There was a significant difference in LF concentration between different stages of lactation (P<0.001). Mothers with higher LF concentration in colostrum had higher values in the following 2 months. High maternal income and multiple gestation were significantly associated with higher LF levels; in contrast, maternal peripartum infections and male neonatal gender were associated with lower LF levels.

CONCLUSIONS

LF concentration in breast milk of mothers of LBW infants was high and remained elevated even at 1 and 2 months postpartum. LF concentration in colostrum was higher in mothers with higher income and multiple pregnancies, and lower in mothers with peripartum infections.

Probiotics to prevent necrotising enterocolitis and nosocomial infection in very low birth weight preterm infants

The aim of the study was to determine whether routine probiotic supplementation (RPS) with Lactobacillus rhamnosus GG (LGG) or Lactobacillus acidophilus +Lactobacillus bifidum is associated with reduced risk of necrotising enterocolitis (NEC)≥Stage II in preterm neonates born at ≤32 weeks' gestation. We conducted a retrospective cohort study on the effect of probiotic supplementation in very low birth weight infants in our neonatal unit by comparing two periods: before and after supplementation. The incidence of NEC≥Stage II, late-onset sepsis and all-cause mortality was compared for an equal period 'before' (Period I) and 'after' (Period II) RPS with LGG or L. acidophillus+L. bifidum. Multivariate logistic regression analysis was conducted to adjust for relevant confounders. The study population was composed of 261 neonates (Period I v. II: 134 v. 127) with comparable gestation duration and birth weights. In <32 weeks, we observed a significant reduction in NEC≥Stage II (11·3 v. 4·8 %), late-onset sepsis (16 v. 10·5 %) and mortality (19·4 v. 2·3 %). The benefits in neonates aged ≤27 weeks did not reach statistical significance. RPS with LGG or L. acidophillus+L. bifidum is associated with a reduced risk of NEC≥Stage II, late-onset sepsis and mortality in preterm neonates born at ≤32 weeks' gestation.

The Importance of Human Milk for Immunity in Preterm Infants

The immune system of preterm infants is immature, placing them at increased risk for serious immune-related complications. Human milk provides a variety of immune protective and immune maturation factors that are beneficial to the preterm infant's poorly developed immune system. The most studied immune components in human milk include antimicrobial proteins, maternal leukocytes, immunoglobulins, cytokines and chemokines, oligosaccharides, gangliosides, nucleotides, and long-chain polyunsaturated fatty acids. There is growing evidence that these components contribute to the lower incidence of immune-related conditions in the preterm infant. Therefore, provision of these components in human milk, donor milk, or formula may provide immunologic benefits.

Pathogenesis of NEC: Role of the innate and adaptive immune response

Necrotizing enterocolitis (NEC) is a devastating disease in premature infants with high case fatality and significant morbidity among survivors. Immaturity of intestinal host defenses predisposes the premature infant gut to injury. An abnormal bacterial colonization pattern with a deficiency of commensal bacteria may lead to a further breakdown of these host defense mechanisms, predisposing the infant to NEC. Here, we review the role of the innate and adaptive immune system in the pathophysiology of NEC.

The Role of Mucosal Immunity in the Pathogenesis of Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is the most devastating gastrointestinal disease of prematurity. Although the precise cause is not well understood, the main risk factors thought to contribute to NEC include prematurity, formula feeding, and bacterial colonization. Recent evidence suggests that NEC develops as a consequence of intestinal hyper-responsiveness to microbial ligands upon bacterial colonization in the preterm infant, initiating a cascade of aberrant signaling events, and a robust pro-inflammatory mucosal immune response. We now have a greater understanding of important mechanisms of disease pathogenesis, such as the role of cytokines, immunoglobulins, and immune cells in NEC. In this review, we will provide an overview of the mucosal immunity of the intestine and the relationship between components of the mucosal immune system involved in the pathogenesis of NEC, while highlighting recent advances in the field that have promise as potential therapeutic targets. First, we will describe the cellular components of the intestinal epithelium and mucosal immune system and their relationship to NEC. We will then discuss the relationship between the gut microbiota and cell signaling that underpins disease pathogenesis. We will conclude our discussion by highlighting notable therapeutic advancements in NEC that target the intestinal mucosal immunity.

Bovine lactoferrin free of lipopolysaccharide can induce a proinflammatory response of macrophages

Background

Lactoferrin (LF) is an 80 kDa glycoprotein which is known for its effects against bacteria, viruses and other pathogens. It also has a high potential in nutrition therapy and welfare of people and a variety of animals, including piglets. The ability to bind lipopolysaccharide (LPS) is one of the described anti-inflammatory mechanisms of LF. Previous studies suggested that cells can be stimulated even by LPS-free LF. Therefore, the aim of our study was to bring additional information about this possibility. Porcine monocyte derived macrophages (MDMF) and human embryonic kidney (HEK) cells were stimulated with unpurified LF in complex with LPS and with purified LF without bound LPS.

Results

Both cell types were stimulated with unpurified as well as purified LF. On the other hand, neither HEK0 cells not expressing any TLR nor HEK4a cells transfected with TLR4 produced any pro-inflammatory cytokine transcripts after stimulation with purified LF. This suggests that purified LF without LPS stimulates cells via another receptor than TLR4. An alternative, TLR4-independent, pathway was further confirmed by analyses of the NF-kappa-B-inducing kinase (NIK) activation. Western blot analyses showed NIK which activates different NFκB subunits compared to LF-LPS signaling via TLR4. Though, this confirmed an alternative pathway which is used by the purified LF free of LPS. This stimulation of MDMF led to low, but significant amounts of pro-inflammatory cytokines, which can be considered as a positive stimulation of the immune system.

Conclusion

Our results suggest that LF’s ability is not only to bind LPS, but LF itself may be a stimulant of pro-inflammatory pathways.