Am J Perinatol 2013; 30(02): 081-088
DOI: 10.1055/s-0032-1333131
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Prevention of Nosocomial Infections in Neonatal Intensive Care Units

Paolo Manzoni
1   Neonatology and NICU, “S. Anna” Hospital, Turin, Italy
,
Daniele De Luca
2   Laboratory of Clinical Molecular Biology and Pediatric Intensive Care Unit, University Hospital “A. Gemelli,” Catholic University of the Sacred Heart, Rome, Italy
,
Mauro Stronati
3   Neonatology, IRCCS S. Matteo, Pavia, Italy
,
Evelyne Jacqz-Aigrain
4   Department of Paediatric Pharmacology and Pharmacogenetics, Clinical Investigation Center, Hopital “R. Debré,” Paris, France
,
Giulia Ruffinazzi
3   Neonatology, IRCCS S. Matteo, Pavia, Italy
,
Martina Luparia
1   Neonatology and NICU, “S. Anna” Hospital, Turin, Italy
,
Elena Tavella
1   Neonatology and NICU, “S. Anna” Hospital, Turin, Italy
,
Elena Boano
1   Neonatology and NICU, “S. Anna” Hospital, Turin, Italy
,
Elio Castagnola
5   Infectious Disease Unit, “G. Gaslini” Children's Hospital, Genoa, Italy
,
Michael Mostert
6   Department of Paediatrics, University of Torino, Torino, Italy
,
Daniele Farina
1   Neonatology and NICU, “S. Anna” Hospital, Turin, Italy
› Author Affiliations
Further Information

Address for correspondence and reprint requests

Paolo Manzoni, MD
Neonatology and NICU, S. Anna Hospital
Azienda Ospedaliera Regina Margherita–S. Anna, C.so Spezia 60, 10126 Torino
Italy   

Publication History

25 July 2012

01 November 2012

Publication Date:
04 January 2013 (online)

 

Abstract

Neonatal sepsis causes a huge burden of morbidity and mortality and includes bloodstream, urine, cerebrospinal, peritoneal, and lung infections as well as infections starting from burns and wounds, or from any other usually sterile sites. It is associated with cytokine - and biomediator-induced disorders of respiratory, hemodynamic, and metabolic processes. Neonates in the neonatal intensive care unit feature many specific risk factors for bacterial and fungal sepsis. Loss of gut commensals such as Bifidobacteria and Lactobacilli spp., as occurs with prolonged antibiotic treatments, delayed enteral feeding, or nursing in incubators, translates into proliferation of pathogenic microflora and abnormal gut colonization. Prompt diagnosis and effective treatment do not protect septic neonates form the risk of late neurodevelopmental impairment in the survivors. Thus prevention of bacterial and fungal infection is crucial in these settings of unique patients. In this view, improving neonatal management is a key step, and this includes promotion of breast-feeding and hygiene measures, adoption of a cautious central venous catheter policy, enhancement of the enteric microbiota composition with the supplementation of probiotics, and medical stewardship concerning H2 blockers with restriction of their use. Additional measures may include the use of lactoferrin, fluconazole, and nystatin and specific measures to prevent ventilator associated pneumonia.


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Sepsis-related morbidity and mortality is an increasing concern in all neonatal intensive care units (NICUs), and the reported incidences are dramatically high regardless of the improvements in the quality of neonatal assistance.[1]

Neonatal sepsis includes bloodstream, urine, cerebrospinal, peritoneal, and lung infections, as well as infections starting from burns and wounds or from any other usually sterile site. It is associated with cytokine- and biomediator-induced disorders of respiratory, hemodynamic, and metabolic processes that are triggered by infections.

Many specific risk factors account for the increased risk of bacterial and fungal sepsis in such patients, including the use of broad-spectrum antimicrobial drugs, parenteral nutrition, acid inhibitors, and steroids, as well as the systematic and long-lasting use of invasive devices such as central venous catheter (CVC) and endotracheal tube.

Preterm neonates in NICU are at high risk of intestinal disorders with proliferation of a pathogenic microflora, because treatment with antibiotics, total parenteral nutrition (TPN), or nursing in incubators may delay or impair the intestinal colonization process. Loss of gut commensals such as Bifidobacteria spp. and Lactobacilli spp., due to the difficulties in oral feeding or a slower acquisition of them in preterm neonates, translates into an increased susceptibility to abnormal gut colonization. For all these reasons, the digestive tract is regarded as an important reservoir and site for colonization by all kinds of pathogens and subsequent sepsis in preterm infants.

Immature or injured skin and impaired gut barriers allow dissemination of many organisms (among them, Staphylococci and Candida spp.) from various colonizing sites.

Infants with complicated gastrointestinal diseases are at increased risk due to abdominal surgery and prolonged periods of TPN and ileus. In addition, many critically ill infants subjected to mechanical ventilation are at high risk of ventilator-associated pneumonia (VAP) that may in turn determine sepsis and other long-term negative outcomes.

Due to the high incidence of negative outcomes in sepsis survivors,[2] prevention of bacterial and fungal colonization and infection is the key in these settings.

In this article, the currently available strategies to prevent infections in NICU patients will be reviewed ([Table 1]).

Table 1

Overview of Preventive Measures to Reduce Risk for Sepsis in NICU

Neonatal management

  • Breast-feeding with fresh human milk

  • Promotion of enteral feeding

  • Hygiene measures

  • CVC management policies

  • CVC bundles

  • In-line filters

  • Enteric microbiota composition enhancement with the use of probiotics

  • H2 blockers and steroids restrictions

  • Antibiotic stewardship

  • Stewardship in TPN use

  • Prevention of VAP

Pharmacological prophylactic interventions

  • General anti-infective prophylaxis: bioactive substances, probiotics, lactoferrin

  • Specific antifungal prophylaxis: fluconazole, nystatin

  • Specific anti-RSV prophylaxis: palivizumab

Abbreviations: CVC, central venous catheter; NICU, neonatal intensive care unit; RSV, Respiratory Syncitial Virus; TPN, total parenteral nutrition; VAP, ventilator-associated pneumonia.


Prevention of Sepsis: What Does Not Work

In the last years, several promising strategies have been assessed and have been ineffective in preventing sepsis.

Recent evidence provided by large, multicenter trials showed that the administration of glutamine, immunoglobulins (either pooled immunoglobulins or specific antistaphylococcal enriched donor's immunoglobulins, or the monoclonal antibody pagibaximab) had no benefits in preventing the incidence and severity of neonatal late-onset sepsis. As a result, these potential approaches are not currently recommended.

Glutamine is one of the most abundant amino acids in both plasma and human milk, with trophic actions on enterocytes and gut integrity,[3] but it is still not routinely included in standard amino acid solutions. Some studies suggested that parenteral nutrition supplemented with glutamine may reduce sepsis and mortality in critically ill adults.[4] Some reports advocated a similar benefit also in extremely low-birth-weight (ELBW) infants.[5] A multicenter, randomized, double-masked, clinical trial was thus conducted to reveal possible beneficial effects of glutamine in preterm infants.[6] ELBW infants (weighing between 401 and 1000 g) were randomized to receive within 72 hours of birth either a usual amino acid solution with no glutamine (control) or an isonitrogenous amino acid solution with 20% glutamine whenever they received TPN. Primary outcome was death or late-onset sepsis. Of the 721 infants who were assigned to glutamine supplementation, 370 (51%) died or developed late-onset sepsis, as compared with 343 of the 712 infants (48%) assigned to control (relative risk: 1.07; 95% confidence interval: 0.97 to 1.17). Glutamine had no effect on tolerance of enteral feeds, necrotizing enterocolitis, or growth. No significant adverse events were observed with glutamine supplementation. The conclusion was that parenteral glutamine supplementation did not decrease mortality or the incidence of late-onset sepsis in ELBW infants. Similar results have been obtained by other two trials of glutamine supplementation.[7] [8] Consequently, routine use of parenteral glutamine supplementation cannot be recommended in this population.

Also therapy with intravenous immune globulins (either pooled or specifically enriched against some pathogen) has proved to be not effective both in prevention and on the outcomes of suspected or proven neonatal sepsis.

The Immunoglobulin Neonatal International Study (INIS) Collaborative group conducted an International Multicenter trial involving 113 hospitals in 9 countries.[9] In all, 3,493 infants were randomized to receive two infusions of either polyvalent immunoglobulin G (IgG) immune globulin (at a dose of 500 mg/kg) or a matching placebo 48 hours apart. No effect, in terms of death or major disability at the age of two years, could be demonstrated.

Similar disappointing findings were so far obtained by studies addressing the potential benefit of antistaphylococcal immunoglobulins for the prevention of staphylococcal infection in very low-birth-weight (VLBW) infants. A recent Cochrane review analyzed all eligible randomized and quasi-randomized studies in this area.[10] Three eligible studies were included involving a total of 2,701 VLBW neonates. No significant differences in the risk of staphylococcal infection between two antistaphylococcal studied drugs (INH A-21 Veronate,[11] Inhibitex Inc., Alpharetta, GA, USA and also Altastaph, Nabi Biopharmaceuticals Inc., Rockville, MD, USA) versus placebo could be demonstrated. The authors concluded that both types of antistaphylococcal immunoglobulins are not recommended for prevention of staphylococcal infections in preterm or VLBW neonates and that further research to investigate the efficacy and the impact on long-term neurodevelopmental outcome of other products, such as pagibaximab, was needed.

Pagibaximab is a recently developed chimeric monoclonal antibody against lipoteichoic acid, a component of the cell membrane of many gram-positive organisms, particularly represented in all Staphylococcus spp. It reacts with coagulase-negative staphylococci and Staphylococcus aureus isolate strains and was granted “orphan drug status” in 2000. An investigational pipeline has been developed over the last decade to provide evidence supporting the claim of prevention of staphylococcal sepsis in VLBW infants.

In a preliminary phase I study, the safety, pharmacokinetics, and pharmacodynamics of pagibaximab were assessed and no major adverse effects were noticed.[12] The antibody was effective against staphylococci preclinically and seemed safe and well tolerated.

A phase IIa, randomized, double-blind, placebo-controlled trial was therefore conducted evaluating also the effects on staphylococcal sepsis. Some dozens of VLBW neonates were randomized to receive once-a-week pagibaximab (90 or 60 mg/kg) or placebo infusions since the early days of life. The results showed that infants who received 90 mg/kg did not feature any staphylococcal sepsis episode. Pagibaximab had a linear pharmacokinetic trend with a 14.5-day half-life and was not immunogenic. However, the target protective levels < 500 μg/mL were only consistently achieved after two to three doses.[13]

These promising findings prompted the organization of a large phase IIb, multicenter, randomized, double-blind, controlled trial that was performed in 100 NICUs across North America and Europe, enrolling 1,579 VLBW infants weighing 600 to 1200 g at birth. The protocol and the preliminary results are described and accessible at www.clinicaltrials.gov.[14]

The primary endpoint was the incidence of infections by Staphylococcus spp. from study days 0 to 35. The report posted at www.clinicaltrials.gov states that no significantly different adverse events occurred in the two groups and that no safety concerns arose. The same report declares that out of 1579 infants analyzed (792 in the pagibaximab and 787 in the placebo groups), 85 in the pagibaximab group versus 79 in the placebo group had staphylococcal sepsis in the first 35 days of study, thus nearly the same.[14]

These findings seem to be consistent with the already reported lack of effectiveness of other strategies based on administration of specific antistaphylococcal immunoglobulins, either pooled from donors or enriched,[9] [12] and seem confirming that administration of specific antistaphylococcal antibodies, whichever the type, is not effective in preventing neonatal late-onset sepsis by Staphylococcus spp. in the nursery.


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Prevention of Sepsis—What Does Work

Nutrition: Human Milk

Availability of essential nutrients is critical for a proper development and maturation of all organs, both in the fetus and in the neonate. Several nutrients play both direct and indirect roles in conditioning the onset of sepsis and infection during the neonatal period. For some nutrients, there is evidence of a protective role against infections also in early infancy (i.e., after the neonatal period).

Human milk contains several substances with putative anti-infective actions, such as lactoferrin (LF), lactoperoxidase, lysozyme, immunoglobulin A (IgA), IgG, immunoglobulin M (IgM), cytokines, interferon, oligosaccharides, bifidogenic factors, platelet-activating factor acetylhydrolase, vitamin E, beta carotene, ascorbic acid.

Also the mucosal trophic effect of human milk on the gut can be seen as an anti-infective mechanism because human milk has a known impact on gut permeability, which changes as a function of age and type of feeding.[15] The feeding of human milk is associated with decreased gut permeability at 28 days of age,[16] meaning that human milk-fed neonates have a more rapid maturation of intestinal epithelium, leading to lower intestinal permeability. This might cause less translocations of pathogens from the gut and ultimately less infections and necrotizing enterocolitis (NEC).

Which factors in maternal milk could account for this? LF possibly plays a major role. Experimental data obtained in human gut cell lines showed that enterocytes exposed to high LF concentrations respond with a potent and rapid increase in cell proliferation, whereas the same cells when exposed to low LF concentrations show enhancement and stimulation of intestinal differentiation. These experiments also reported that bovine LF has the same extent of activity as human LF.[17] LF is thus a key modulator of intestinal epithelium development, and the speculation is that the higher concentrations of LF in colostrum contribute to the early proliferation of intestinal cells, which then differentiate as a result of its decreased concentrations in mature milk.

Of importance, beneficial effects of breast milk in prevention of infections depend on the amounts of human milk ingested. Only average intakes higher than 50 mL/kg/d have been associated with a protective effect,[18] as well as only fresh (and not donor) milk has been found to be protective. Pasteurization at 62.5°C for 30 minutes (Holder method) decreases many anti-infective milk substances, and this might explain why in a recent randomized trial of donor human versus preterm formula, the two different types of milk were shown to have the same lack of effect on prevention of sepsis.[19]


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CVC Policy

Strict policies in the management of the CVC are mandatory to prevent or reduce line-associated infections. The duration of a CVC should be correctly monitored as it impacts on the occurrence of a line-associated infection. After 15 days of maintenance, the odds of developing a bloodstream infection increase abruptly.[20] Therefore, scheduled removal of percutaneously inserted CVC should be considered, at least in at-risk ELBW neonates, even in absence of signs of suspected sepsis. This recommendation is different from the usual practice in adult and pediatric critical care, and the difference in patient populations (the need for a long-term Total Parenteral Nutrition (TPN) in preemies) may explain this situation. Anyway, further, more robust evidence has to be produced to really clarify this issue.

In terms of best use of human resources, “proactive” management of percutaneously inserted central catheters results in decreased incidence of infection in the ELBW population. In a single NICU study, the creation of a dedicated task force for the CVC management produced a two-third reduction in the incidence of line-associated infections (from 15.8 infections/1000 catheters per day to only 5.1 infections/1000 catheters per day).[21] Additionally, recent evidence confirmed that standardization of CVC placement and maintenance can reduce the risk for bloodstream infection by 50%.[22]

The use of “in-line filters” is also a promising approach. Particulate contamination due to infusion therapy carries a potential health risk, in terms of occurrence of systemic inflammatory response syndrome, organ failure, thrombosis, and ultimately sepsis. A recent single-center, prospective, randomized controlled trial conducted in a pediatric intensive care unit assessed the effects of filtration of intravenous fluids on the reduction of complications in critically ill children.[23] The authors demonstrated a significant reduction in the overall complication rate (40.9% versus 30.9%;p = 0.003) for the filter group. In detail, the incidence of systemic inflammatory response syndrome was significantly lower (30.3% versus 22.4%; p = 0.01). Pediatric intensive care unit stay and duration of mechanical ventilation were also significantly reduced. However, no significant impact could be shown on the incidence of sepsis. This strategy needs further evaluation specifically designed for sepsis prevention and neonatal settings.

Another option to consider is an “intraremoval” prophylactic strategy. In a recent trial, the administration of two doses of cefazolin during CVC removal and change reduced from 11 to 0% the incidence of coagulase-negative staphylococcal sepsis (number needed to treat: 9).[24] These data might have limited generalizability due to the fact that in many NICUs the proportion of coagulase-negative staphylococci resistant to cefazolin is high. Nevertheless, this is interesting information and deserves further confirmation addressing also the possible differences in risk between various types of catheters: in fact, umbilical central catheter seems at much lower risk than peripherally inserted CVC.[25]


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Restriction of H2-Blockers

Use of H2 blockers is associated with increased rates of infections in preterm neonates in NICU and should therefore be limited or avoided. The acid gastric barrier is the most primitive way of contrasting pathogens, and its impairment is obviously detrimental for the preterm host.

In a retrospective study of 569 infants in NICU over 3 years, Bianconi et al examined the effect of ranitidine on the incidence of late-onset sepsis and concluded that after controlling for all possible confounding factors, infants receiving ranitidine were at approximately 7 times greater risk of late-onset sepsis (odds ratio [OR] 6.99; 95% confidence interval [CI]: 3.78 to 12.94; p < 0.0001).[26] More recently, other reports confirmed these findings, suggesting that the use of ranitidine or other H2 blockers in the nursery should be avoided.[27] [28] In this view, no data are currently available on the impact of proton pump inhibitors (e.g., omeprazole). This class of antacid drugs operate by a different pharmacological mechanism but still result in increased gastric pH and probable altered gastrointestinal flora, thus—at least in theory—its use should be carefully considered in neonates at high risk for sepsis.


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Probiotics

Probiotics colonize the neonate since the early moments of life, starting from labor when the offspring ingests microorganisms belonging to the normal commensal flora of the maternal genitourinary tract. Should the baby be prematurely born, or through cesarean section, or exposed to antibiotics since the early moments of life, this natural process may not occur or be impaired.

Probiotics have known immunomodulating and anti-infective activities, as they produce substances with bacteriostatic/bactericidal actions (e.g., the Lactobacillus reuterii produce the so-called reutericyclin, an antibiotic peptide[29]), compete for adhesion to gut cells displacing the pathogens,[30] and finally influence intestinal permeability.[31]

The impact of healthy gut colonization has been confirmed by studies that showed how colonization with Bacteroides spp. increases the number of gut cells producing IgA, IgG, and IgM in the first months of life.[32]

Probiotics have a known effect in the prevention of NEC, which is often related to sepsis.[33] A recent Cochrane review stated that enteral supplementation of probiotics prevents severe NEC (risk ratio 0.35), sepsis (risk ratio 0.9), and all-cause mortality (risk ratio 0.4) in preterm infants.[34]

Moreover, Lactobacillus rhamnosus GG and L. reuterii proved effective in preventing gut colonization by Candida spp.,[35] a process that often precedes fungal sepsis. [Table 2] [36] [37] [63] [64] [65] [66] [67] [68] [69] [70] [71] summarizes the results from the main trials of probiotics for prevention of Candida colonization. The safety of probiotics has been recently confirmed in a retrospective, two-center study reporting on the absence of any adverse effect or microbiologic issue over 6 years of routine L. rhamnosus LGG. administration in VLBW neonates admitted in two large Italian NICUs.[36]

Table 2

Main Rrials of Probiotics to Prevent LOS or Colonization by Candida spp. in Preterm Infants in NICU

Probiotic used

Primary outcome

Incidence in the probiotic group (%)

Incidence in the placebo group (%)

p value

Manzoni et al, 2006[35]

Lactobacillus rhamnosus GG

Candida gut colonization in <1500-g neonates

23.1

48.8

0.01

Romeo et al, 2011[37]

Lactobacillus reuterii

Candida gut colonization in <2500-g neonates

7.1

22.9

0.01

Romeo et al, 2011[37]

Lactobacillus rhamnosus GG

Candida gut colonization in <2500-g neonates

10.7

22.9

0.01

Manzoni et al, 2006[35]

Lactobacillus rhamnosus GG

LOS in <1500-g neonates

48.7

53.6

NS

Kitajima et al, 1997[63]

Bifidobacterium breve

LOS in <1500 g neonates

2.2

0

NS

Dani et al, 2002[64]

Lactobacillus rhamnosus GG

LOS in <1500-g neonates

4.7

4.1

NS

Costalos et al, 2003[65]

Saccharomyces boulardii

LOS in <1500-g neonates

5.8

8.3

NS

Bin-Nun et al, 2005[66]

Bifidobacterium infantis; Streptococcus thermophilus; Bifidobacterium bifidus

LOS in <1500-g neonates

43

32.89

NS

Lin et al, 2005[67]

Lactobacillus acidophilus, Bifidobacterium infantis

LOS in <1500-g neonates

12.2

19.2

NS

Stratiki et al, 2007[68]

Bifidobacterium longum

LOS in <1500-g neonates

0

9.7

0.09

Lin et al, 2008[69]

Lactobacillus acidophilus, Bifidobacterium bifidus

LOS in <1500-g neonates

19.8

11.5

0.06

Samanta et al, 2009[70]

Bifidobacterium lactis; Lactobacillus acidophilus, Bifidobacterium bifidus

LOS in <1500-g neonates

14.2

29.5

0.02

Rougé et al, 2009[71]

Lactobacillus rhamnosus GG Bifidobacterium longum

LOS in <1500-g neonates

33.3

26.5

NS

Abbreviations: LOS, late-onset sepsis; NICU, neonatal intensive care unit; NS, not significant.


Despite the important available evidence, major areas are still in need of further studies and clarifications before probiotics can be more broadly embraced, including the scattered availability of well-defined pharmacological-grade products (as opposed to nutritional supplement grade) in many countries/settings, the lack of data on long-term neurodevelopmental follow-up in infants fed probiotics since birth, and the identification of which species of probiotics is preferable for each different clinical purpose, given that that different probiotic species may have different actions and targets.


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Fluconazole

Fluconazole prophylaxis is effective in preventing Candida spp. infection in infants < 1500 g. A recent meta-analysis with Mantel-Haenszel methods including 10 studies (7 retrospective studies and 3 randomized controlled trials)[37] shows that fluconazole prophylaxis reduces:

  • ∀ the chance of developing invasive fungal infection (IFI) in high-risk infants <1000 g (odds ratio (OR) 0.10; 95% confidence interval (CI) 0.05–0.22; p < 0.0001)

  • ∀ the chance of developing IFI in all infants <1500 g (OR 0.15; 95% CI 0.09–0.26; p < 0.0001)

  • ∀ the overall mortality rate (11% versus 16.3%) in all infants <1500 g (OR 0.74; 95% CI 0.58–0.95; p = 0.017)

  • ∀ the Candida-related mortality (from 25 non-treated infants to 1 fluconazole-treated patient among the 4,208 VLBW infants included in the published studies so far).

Overall, fluconazole prophylaxis decreases invasive fungal infections by 90% in ELBW and by 85% in VLBW infants with all cause mortality decreased by 24%. Fluconazole is currently recommended as a strategy in NICU having a high incidence of fungal infections, and in all those subgroups of neonates with high odds of developing such a devastating disease.[38] [39]


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Nystatin

Nystatin is a nonabsorbed antifungal drug that has been proposed since the 1990s as a feasible approach for prevention of fungal infections in neonates.[38] [40] [41] [42] [43] [44] The highest-quality evidence comes from one only recent comparative trial in which 278 babies were randomized to three arms receiving nystatin, fluconazole, or placebo. The efficacy of nystatin in preventing fungal colonization and invasive infections was deemed similar to that of fluconazole.[45] When grouping together all the other nystatin studies, however, the overall level of evidence reached is lower, as compared with that of fluconazole. However, most data come from retrospective, nonrandomized, or low-quality studies with few of the smallest preterm infants and do not report data on mortality, nor on other major outcomes and on resistances development.

Of note, although intravenous fluconazole acts on many levels, oral nystatin may only reduce intestinal colonization. Moreover, nystatin has an extremely high osmolarity (10 times higher than fluconazole) and this paradoxically might be a relevant risk factor for NEC.[46]


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Lactoferrin

A new approach toward reduction of sepsis and NEC might involve the use of bioactive substances with known anti-infective properties. LF is a mammalian milk glycoprotein involved in innate immune host defenses and can reduce the incidence of late-onset sepsis in VLBW infants [47] and of NEC in animal models.[48] The bovine isoform is nearly homologous to the human one. LF targets all pathogens, has bifidogenic properties, and enhances maturation of the nascent gut.[49] In a recent trial, bovine LF produced a 65% decrease in late-onset sepsis and a significant decrease in NEC of any stage of severity.[50]

Moreover, LF seems to have a strong candidacidal activity and might have a role also specifically for fungal infection prevention.[51] [52] In fact, a randomized controlled trial enrolling 472 neonates demonstrated a reduction in the risk of invasive fungal infection for LF-treated infants (relative risk between 3.8 and 11, with a number needed to treat between 14 and 17.5).[53] As no adverse effects or treatment intolerances have been reported to date, the role of LF in the management of infections and NEC in NICU looks very promising and worthy of future, larger-sized trials to confirm these findings.


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The Special Case of VAP

VAP represents a particular challenge because it affects most critically ill patients needing mechanical ventilation for their respiratory failure, including preterm neonates. VAP is responsible for a vicious cycle because it leads to a longer duration of ventilation, and as the additional days of ventilation is inversely related to the birth weight,[54] [55] this may obviously affect the insurgence of bronchopulmonary dysplasia and sepsis. Conversely, a previous episode of sepsis is a significant risk factor for VAP occurrence in preterm babies.[56] It is not surprising that VAP represents a significant risk factor for death in ELBW babies (OR: 3.4; 95% CI: 1.20 to 12.31).[56] The risk for VAP is significantly higher below 28 weeks' gestation,[56] thus smaller babies are at greater risk for concurrent complications. Despite its importance and the fact that VAP is among the commonest nosocomial infections in pediatric critical care units in Europe and North-America,[57] [58] few data are available about its occurrence in NICUs, and a certain degree of variability in VAP definitions in the different studies exists. Thus no clear strategy for its prevention is currently available.

Preventative proposed interventions include early extubation strategies and switching to noninvasive respiratory support, the reduction of transfers of the babies outside the NICU, and frequent changes of the ventilator circuits; however, more data are needed to properly evaluate the efficacy of each intervention.[59] [60]

Very recently, two intriguing new approaches have been proposed. Ryan et al used an ultraviolet germicidal irradiation in the heating ventilation and air-conditioning system of their NICU and observed a significantly reduced tracheal microbial colonization and VAP (from 74 to 39%; p = 0.04; relative risk: 1.89; number needed to treat 2.85).[61] Christensen et al proposed the use of a low sodium saline solution for airway care and bronchoalveolar lavage in intubated neonates. This solution should decrease the incidence of VAP by reducing the damage to the innate antimicrobial system of airways subjected to serial lavages (as happens in long-term ventilated neonates). These authors observed a reduction in VAP incidence from 4.2/1,000 episodes in the control group to 1.6 VAPs/1,000 ventilator days in the treatment arm (p = 0.04) and also a lower incidence of chronic lung disease (p < 0.001).[62]

Even though these findings are preliminary and produced by trials that may not be free from biases, they look promising in identifying new lines of research to prevent VAP and concurrent complications including neonatal sepsis.


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Disclosures

Authors P.M. and E.A.J. collaborate in the framework of several EU-funded and endorsed projects in the area of antifungal safety and treatment in neonates. They represent in these projects the TINN European collaborative group. E.A.J. and P.M. are, respectively, coordinator and work package leader of the FP7 European Project Treat Infections in Neonates (TINN). P.M. and D.F. are, respectively, Chairman and Advisor of the Scientific Committee of the Foundation “Crescere Insieme al S. Anna-ONLUS.”

  • References

  • 1 Manzoni P, Rizzollo S, Decembrino L , et al. Recent advances in prevention of sepsis in the premature neonates in NICU. Early Hum Dev 2011; 87 (Suppl. 01) S31-S33
  • 2 Stoll BJ, Hansen NI, Adams-Chapman I , et al; National Institute of Child Health and Human Development Neonatal Research Network. Neurodevelopmental and growth impairment among extremely low-birth-weight infants with neonatal infection. JAMA 2004; 292: 2357-2365
  • 3 Panigrahi P, Gewolb IH, Bamford P, Horvath K. Role of glutamine in bacterial transcytosis and epithelial cell injury. JPEN J Parenter Enteral Nutr 1997; 21: 75-80
  • 4 Lacey JM, Wilmore DW. Is glutamine a conditionally essential amino acid?. Nutr Rev 1990; 48: 297-309
  • 5 van den Berg A, van Elburg RM, Westerbeek EA, Twisk JW, Fetter WP. Glutamine-enriched enteral nutrition in very-low-birth-weight infants and effects on feeding tolerance and infectious morbidity: a randomized controlled trial. Am J Clin Nutr 2005; 81: 1397-1404
  • 6 Poindexter BB, Ehrenkranz RA, Stoll BJ , et al; National Institute of Child Health and Human Development Neonatal Research Network. Parenteral glutamine supplementation does not reduce the risk of mortality or late-onset sepsis in extremely low birth weight infants. Pediatrics 2004; 113: 1209-1215
  • 7 Vaughn P, Thomas P, Clark R, Neu J. Enteral glutamine supplementation and morbidity in low birth weight infants. J Pediatr 2003; 142: 662-668
  • 8 Mohamad Ikram I, Quah BS, Noraida R, Djokomuljanto S, Faris Irfan CY, Van Rostenberghe H. A randomised controlled trial of glutamine-enriched neonatal parenteral nutrition in Malaysia. Singapore Med J 2011; 52: 356-360
  • 9 Brocklehurst P, Farrell B, King A , et al; INIS Collaborative Group. Treatment of neonatal sepsis with intravenous immune globulin. N Engl J Med 2011; 365: 1201-1211
  • 10 Shah PS, Kaufman DA. Antistaphylococcal immunoglobulins to prevent staphylococcal infection in very low birth weight infants. Cochrane Database Syst Rev 2009; (2) CD006449
  • 11 DeJonge M, Burchfield D, Bloom B , et al. Clinical trial of safety and efficacy of INH-A21 for the prevention of nosocomial staphylococcal bloodstream infection in premature infants. J Pediatr 2007; 151: 260-265 , e1
  • 12 Weisman LE, Thackray HM, Garcia-Prats JA , et al. Phase 1/2 double-blind, placebo-controlled, dose escalation, safety, and pharmacokinetic study of pagibaximab (BSYX-A110), an antistaphylococcal monoclonal antibody for the prevention of staphylococcal bloodstream infections, in very-low-birth-weight neonates. Antimicrob Agents Chemother 2009; 53: 2879-2886
  • 13 Weisman LE, Thackray HM, Steinhorn RH , et al. A randomized study of a monoclonal antibody (pagibaximab) to prevent staphylococcal sepsis. Pediatrics 2011; 128: 271-279
  • 14 ClinicalTrials.gov. Safety and efficacy of pagibaximab injection in very low birth weight neonates for prevention of staphylococcal sepsis. Available at: http://www.clinicaltrials.gov/ct2/show/study/NCT00646399?term=pagibaximab&rank=1&sect=X3015 . Accessed July 18, 2012
  • 15 Goldman AS. Modulation of the gastrointestinal tract of infants by human milk. Interfaces and interactions. An evolutionary perspective. J Nutr 2000; 130 (2S, Suppl) 426S-431S
  • 16 Shulman RJ, Schanler RJ, Lau C, Heitkemper M, Ou CN, Smith EO. Early feeding, antenatal glucocorticoids, and human milk decrease intestinal permeability in preterm infants. Pediatr Res 1998; 44: 519-523
  • 17 Buccigrossi V, de Marco G, Bruzzese E , et al. Lactoferrin induces concentration-dependent functional modulation of intestinal proliferation and differentiation. Pediatr Res 2007; 61: 410-414
  • 18 Schanler RJ, Shulman RJ, Lau C. Feeding strategies for premature infants: beneficial outcomes of feeding fortified human milk versus preterm formula. Pediatrics 1999; 103 (6 Pt 1) 1150-1157
  • 19 Schanler RJ, Lau C, Hurst NM, Smith EO. Randomized trial of donor human milk versus preterm formula as substitutes for mothers' own milk in the feeding of extremely premature infants. Pediatrics 2005; 116: 400-406
  • 20 Advani S, Reich NG, Sengupta A, Gosey L, Milstone AM. Central line-associated bloodstream infection in hospitalized children with peripherally inserted central venous catheters: extending risk analyses outside the intensive care unit. Clin Infect Dis 2011; 52: 1108-1115
  • 21 Golombek SG, Rohan AJ, Parvez B, Salice AL, LaGamma EF. “Proactive” management of percutaneously inserted central catheters results in decreased incidence of infection in the ELBW population. J Perinatol 2002; 22: 209-213
  • 22 Taylor T, Massaro A, Williams L , et al. Effect of a dedicated percutaneously inserted central catheter team on neonatal catheter-related bloodstream infection. Adv Neonatal Care 2011; 11: 122-128
  • 23 Jack T, Boehne M, Brent BE , et al. In-line filtration reduces severe complications and length of stay on pediatric intensive care unit: a prospective, randomized, controlled trial. Intensive Care Med 2012; 38: 1008-1016
  • 24 Hemels MA, van den Hoogen A, Verboon-Maciolek MA, Fleer A, Krediet TG. Prevention of neonatal late-onset sepsis associated with the removal of percutaneously inserted central venous catheters in preterm infants. Pediatr Crit Care Med 2011; 12: 445-448
  • 25 Hei MY, Zhang XC, Gao XY , et al. Catheter-related infection and pathogens of umbilical venous catheterization in a neonatal intensive care unit in China. Am J Perinatol 2012; 29: 107-114
  • 26 Bianconi S, Gudavalli M, Sutija VG, Lopez AL, Barillas-Arias L, Ron N. Ranitidine and late-onset sepsis in the neonatal intensive care unit. J Perinat Med 2007; 35: 147-150
  • 27 Terrin G, Passariello A, De Curtis M , et al. Ranitidine is associated with infections, necrotizing enterocolitis, and fatal outcome in newborns. Pediatrics 2012; 129: e40-e45
  • 28 Graham III PL, Begg MD, Larson E, Della-Latta P, Allen A, Saiman L. Risk factors for late onset gram-negative sepsis in low birth weight infants hospitalized in the neonatal intensive care unit. Pediatr Infect Dis J 2006; 25: 113-117
  • 29 Gänzle MG. Reutericyclin: biological activity, mode of action, and potential applications. Appl Microbiol Biotechnol 2004; 64: 326-332
  • 30 Walter J, Britton RA, Roos S. Host-microbial symbiosis in the vertebrate gastrointestinal tract and the Lactobacillus reuteri paradigm. Proc Natl Acad Sci U S A 2011; 108 (Suppl. 01) 4645-4652
  • 31 Ahrne S, Hagslatt ML. Effect of lactobacilli on paracellular permeability in the gut. Nutrients 2011; 3: 104-117
  • 32 Grönlund MM, Arvilommi H, Kero P, Lehtonen OP, Isolauri E. Importance of intestinal colonisation in the maturation of humoral immunity in early infancy: a prospective follow up study of healthy infants aged 0–6 months. Arch Dis Child Fetal Neonatal Ed 2000; 83: F186-F192
  • 33 Deshpande G, Rao S, Patole S, Bulsara M. Updated meta-analysis of probiotics for preventing necrotizing enterocolitis in preterm neonates. Pediatrics 2010; 125: 921-930
  • 34 Alfaleh K, Anabrees J, Bassler D, Al-Kharfi T. Probiotics for prevention of necrotizing enterocolitis in preterm infants. Cochrane Database Syst Rev 2011; (3) CD005496
  • 35 Manzoni P, Mostert M, Leonessa ML , et al. Oral supplementation with Lactobacillus casei subspecies rhamnosus prevents enteric colonization by Candida species in preterm neonates: a randomized study. Clin Infect Dis 2006; 42: 1735-1742
  • 36 Manzoni P, Lista G, Gallo E , et al. Routine Lactobacillus rhamnosus GG administration in VLBW infants: a retrospective, 6-year cohort study. Early Hum Dev 2011; 87 (Suppl. 01) S35-S38
  • 37 Romeo MG, Romeo DM, Trovato L , et al. Role of probiotics in the prevention of the enteric colonization by Candida in preterm newborns: incidence of late-onset sepsis and neurological outcome. J Perinatol 2011; 31: 63-69
  • 38 Kaufman DA, Manzoni P. Strategies to prevent invasive candidal infection in extremely preterm infants. Clin Perinatol 2010; 37: 611-628
  • 39 Manzoni P, Mostert M, Jacqz-Aigrain E, Farina D. The use of fluconazole in neonatal intensive care units. Arch Dis Child 2009; 94: 983-987
  • 40 Sims ME, Yoo Y, You H, Salminen C, Walther FJ. Prophylactic oral nystatin and fungal infections in very-low-birthweight infants. Am J Perinatol 1988; 5: 33-36
  • 41 Ozturk MA, Gunes T, Koklu E, Cetin N, Koc N. Oral nystatin prophylaxis to prevent invasive candidiasis in neonatal intensive care unit. Mycoses 2006; 49: 484-492
  • 42 Ganesan K, Harigopal S, Neal T, Yoxall CW. Prophylactic oral nystatin for preterm babies under 33 weeks' gestation decreases fungal colonisation and invasive fungaemia. Arch Dis Child Fetal Neonatal Ed 2009; 94: F275-F278
  • 43 Howell A, Isaacs D, Halliday R. Australasian Study Group For Neonatal Infections. Oral nystatin prophylaxis and neonatal fungal infections. Arch Dis Child Fetal Neonatal Ed 2009; 94: F429-F433
  • 44 Violaris K, Carbone T, Bateman D, Olawepo O, Doraiswamy B, LaCorte M. Comparison of fluconazole and nystatin oral suspensions for prophylaxis of systemic fungal infection in very low birthweight infants. Am J Perinatol 2010; 27: 73-78
  • 45 Aydemir C, Oguz SS, Dizdar EA , et al. Randomised controlled trial of prophylactic fluconazole versus nystatin for the prevention of fungal colonisation and invasive fungal infection in very low birth weight infants. Arch Dis Child Fetal Neonatal Ed 2011; 96: F164-F168
  • 46 De Carolis MP, Lacerenza S, De Luca D, Bersani I, Costa S, Romagnoli C. Is neonatal antiretroviral therapy a risk factor for NEC occurrence?. Turk J Pediatr 2010; 52: 108-110
  • 47 Manzoni P, Rinaldi M, Cattani S , et al; Italian Task Force for the Study and Prevention of Neonatal Fungal Infections, Italian Society of Neonatology. Bovine lactoferrin supplementation for prevention of late-onset sepsis in very low-birth-weight neonates: a randomized trial. JAMA 2009; 302: 1421-1428
  • 48 Adamkin DH. Mother's milk, feeding strategies, and lactoferrin to prevent necrotizing enterocolitis. JPEN J Parenter Enteral Nutr 2012; 36 (1, Suppl) 25S-29S
  • 49 Manzoni P, Mostert M, Stronati M. Lactoferrin for prevention of neonatal infections. Curr Opin Infect Dis 2011; 24: 177-182
  • 50 Manzoni P, Decembrino L, Stolfi I , et al; Italian Task Force for the Study and Prevention of Neonatal Fungal Infections; Italian Society of Neonatology. Lactoferrin and prevention of late-onset sepsis in the pre-term neonates. Early Hum Dev 2010; 86 (Suppl. 01) 59-61
  • 51 Lupetti A, Brouwer CP, Dogterom-Ballering HE , et al. Release of calcium from intracellular stores and subsequent uptake by mitochondria are essential for the candidacidal activity of an N-terminal peptide of human lactoferrin. J Antimicrob Chemother 2004; 54: 603-608
  • 52 Ward PP, Paz E, Conneely OM. Multifunctional roles of lactoferrin: a critical overview. Cell Mol Life Sci 2005; 62: 2540-2548
  • 53 Manzoni P, Stolfi I, Messner H , et al; Italian Task Force for the Study and Prevention of Neonatal Fungal Infections–the Italian Society of Neonatology. Bovine lactoferrin prevents invasive fungal infections in very low birth weight infants: a randomized controlled trial. Pediatrics 2012; 129: 116-123
  • 54 Cordero L, Ayers LW, Miller RR, Seguin JH, Coley BD. Surveillance of ventilator-associated pneumonia in very-low-birth-weight infants. Am J Infect Control 2002; 30: 32-39
  • 55 Cordero L, Sananes M, Coley B, Hogan M, Gelman M, Ayers LW. Ventilator-associated pneumonia in very low-birth-weight infants at the time of nosocomial bloodstream infection and during airway colonization with Pseudomonas aeruginosa . Am J Infect Control 2000; 28: 333-339
  • 56 Apisarnthanarak A, Holzmann-Pazgal G, Hamvas A, Olsen MA, Fraser VJ. Ventilator-associated pneumonia in extremely preterm neonates in a neonatal intensive care unit: characteristics, risk factors, and outcomes. Pediatrics 2003; 112 (6 Pt 1) 1283-1289
  • 57 Raymond J, Aujard Y. European Study Group. Nosocomial infections in pediatric patients: a European, multicenter prospective study. Infect Control Hosp Epidemiol 2000; 21: 260-263
  • 58 Stover BH, Shulman ST, Bratcher DF, Brady MT, Levine GL, Jarvis WR. Pediatric Prevention Network. Nosocomial infection rates in US children's hospitals' neonatal and pediatric intensive care units. Am J Infect Control 2001; 29: 152-157
  • 59 Garland JS. Strategies to prevent ventilator-associated pneumonia in neonates. Clin Perinatol 2010; 37: 629-643
  • 60 Vendettuoli V, De Cunto A, Tana M , et al. [Pulmonary infections in preterm newborns]. Minerva Pediatr 2007; 59: 97-105
  • 61 Ryan RM, Wilding GE, Wynn RJ, Welliver RC, Holm BA, Leach CL. Effect of enhanced ultraviolet germicidal irradiation in the heating ventilation and air conditioning system on ventilator-associated pneumonia in a neonatal intensive care unit. J Perinatol 2011; 31: 607-614
  • 62 Christensen RD, Henry E, Baer VL , et al. A low-sodium solution for airway care: results of a multicenter trial. Respir Care 2010; 55: 1680-1685
  • 63 Kitajima H, Sumida Y, Tanaka R, Yuki N, Takayama H, Fujimura M. Early administration of Bifidobacterium breve to preterm infants: randomised controlled trial. Arch Dis Child Fetal Neonatal Ed 1997; 76: F101-F107
  • 64 Dani C, Biadaioli R, Bertini G, Martelli E, Rubaltelli FF. Probiotics feeding in prevention of urinary tract infection, bacterial sepsis and necrotizing enterocolitis in preterm infants. A prospective double-blind study. Biol Neonate 2002; 82: 103-108
  • 65 Costalos C, Skouteri V, Gounaris A , et al. Enteral feeding of premature infants with Saccharomyces boulardii . Early Hum Dev 2003; 74: 89-96
  • 66 Bin-Nun A, Bromiker R, Wilschanski M , et al. Oral probiotics prevent necrotizing enterocolitis in very low birth weight neonates. J Pediatr 2005; 147: 192-196
  • 67 Lin HC, Su BH, Chen AC , et al. Oral probiotics reduce the incidence and severity of necrotizing enterocolitis in very low birth weight infants. Pediatrics 2005; 115: 1-4
  • 68 Stratiki Z, Costalos C, Sevastiadou S , et al. The effect of a bifidobacter supplemented bovine milk on intestinal permeability of preterm infants. Early Hum Dev 2007; 83: 575-579
  • 69 Lin HC, Hsu CH, Chen HL , et al. Oral probiotics prevent necrotizing enterocolitis in very low birth weight preterm infants: a multicenter, randomized, controlled trial. Pediatrics 2008; 122: 693-700
  • 70 Samanta M, Sarkar M, Ghosh P, Ghosh J, Sinha M, Chatterjee S. Prophylactic probiotics for prevention of necrotizing enterocolitis in very low birth weight newborns. J Trop Pediatr 2009; 55: 128-131
  • 71 Rougé C, Piloquet H, Butel MJ , et al. Oral supplementation with probiotics in very-low-birth-weight preterm infants: a randomized, double-blind, placebo-controlled trial. Am J Clin Nutr 2009; 89: 1828-1835

Address for correspondence and reprint requests

Paolo Manzoni, MD
Neonatology and NICU, S. Anna Hospital
Azienda Ospedaliera Regina Margherita–S. Anna, C.so Spezia 60, 10126 Torino
Italy   

  • References

  • 1 Manzoni P, Rizzollo S, Decembrino L , et al. Recent advances in prevention of sepsis in the premature neonates in NICU. Early Hum Dev 2011; 87 (Suppl. 01) S31-S33
  • 2 Stoll BJ, Hansen NI, Adams-Chapman I , et al; National Institute of Child Health and Human Development Neonatal Research Network. Neurodevelopmental and growth impairment among extremely low-birth-weight infants with neonatal infection. JAMA 2004; 292: 2357-2365
  • 3 Panigrahi P, Gewolb IH, Bamford P, Horvath K. Role of glutamine in bacterial transcytosis and epithelial cell injury. JPEN J Parenter Enteral Nutr 1997; 21: 75-80
  • 4 Lacey JM, Wilmore DW. Is glutamine a conditionally essential amino acid?. Nutr Rev 1990; 48: 297-309
  • 5 van den Berg A, van Elburg RM, Westerbeek EA, Twisk JW, Fetter WP. Glutamine-enriched enteral nutrition in very-low-birth-weight infants and effects on feeding tolerance and infectious morbidity: a randomized controlled trial. Am J Clin Nutr 2005; 81: 1397-1404
  • 6 Poindexter BB, Ehrenkranz RA, Stoll BJ , et al; National Institute of Child Health and Human Development Neonatal Research Network. Parenteral glutamine supplementation does not reduce the risk of mortality or late-onset sepsis in extremely low birth weight infants. Pediatrics 2004; 113: 1209-1215
  • 7 Vaughn P, Thomas P, Clark R, Neu J. Enteral glutamine supplementation and morbidity in low birth weight infants. J Pediatr 2003; 142: 662-668
  • 8 Mohamad Ikram I, Quah BS, Noraida R, Djokomuljanto S, Faris Irfan CY, Van Rostenberghe H. A randomised controlled trial of glutamine-enriched neonatal parenteral nutrition in Malaysia. Singapore Med J 2011; 52: 356-360
  • 9 Brocklehurst P, Farrell B, King A , et al; INIS Collaborative Group. Treatment of neonatal sepsis with intravenous immune globulin. N Engl J Med 2011; 365: 1201-1211
  • 10 Shah PS, Kaufman DA. Antistaphylococcal immunoglobulins to prevent staphylococcal infection in very low birth weight infants. Cochrane Database Syst Rev 2009; (2) CD006449
  • 11 DeJonge M, Burchfield D, Bloom B , et al. Clinical trial of safety and efficacy of INH-A21 for the prevention of nosocomial staphylococcal bloodstream infection in premature infants. J Pediatr 2007; 151: 260-265 , e1
  • 12 Weisman LE, Thackray HM, Garcia-Prats JA , et al. Phase 1/2 double-blind, placebo-controlled, dose escalation, safety, and pharmacokinetic study of pagibaximab (BSYX-A110), an antistaphylococcal monoclonal antibody for the prevention of staphylococcal bloodstream infections, in very-low-birth-weight neonates. Antimicrob Agents Chemother 2009; 53: 2879-2886
  • 13 Weisman LE, Thackray HM, Steinhorn RH , et al. A randomized study of a monoclonal antibody (pagibaximab) to prevent staphylococcal sepsis. Pediatrics 2011; 128: 271-279
  • 14 ClinicalTrials.gov. Safety and efficacy of pagibaximab injection in very low birth weight neonates for prevention of staphylococcal sepsis. Available at: http://www.clinicaltrials.gov/ct2/show/study/NCT00646399?term=pagibaximab&rank=1&sect=X3015 . Accessed July 18, 2012
  • 15 Goldman AS. Modulation of the gastrointestinal tract of infants by human milk. Interfaces and interactions. An evolutionary perspective. J Nutr 2000; 130 (2S, Suppl) 426S-431S
  • 16 Shulman RJ, Schanler RJ, Lau C, Heitkemper M, Ou CN, Smith EO. Early feeding, antenatal glucocorticoids, and human milk decrease intestinal permeability in preterm infants. Pediatr Res 1998; 44: 519-523
  • 17 Buccigrossi V, de Marco G, Bruzzese E , et al. Lactoferrin induces concentration-dependent functional modulation of intestinal proliferation and differentiation. Pediatr Res 2007; 61: 410-414
  • 18 Schanler RJ, Shulman RJ, Lau C. Feeding strategies for premature infants: beneficial outcomes of feeding fortified human milk versus preterm formula. Pediatrics 1999; 103 (6 Pt 1) 1150-1157
  • 19 Schanler RJ, Lau C, Hurst NM, Smith EO. Randomized trial of donor human milk versus preterm formula as substitutes for mothers' own milk in the feeding of extremely premature infants. Pediatrics 2005; 116: 400-406
  • 20 Advani S, Reich NG, Sengupta A, Gosey L, Milstone AM. Central line-associated bloodstream infection in hospitalized children with peripherally inserted central venous catheters: extending risk analyses outside the intensive care unit. Clin Infect Dis 2011; 52: 1108-1115
  • 21 Golombek SG, Rohan AJ, Parvez B, Salice AL, LaGamma EF. “Proactive” management of percutaneously inserted central catheters results in decreased incidence of infection in the ELBW population. J Perinatol 2002; 22: 209-213
  • 22 Taylor T, Massaro A, Williams L , et al. Effect of a dedicated percutaneously inserted central catheter team on neonatal catheter-related bloodstream infection. Adv Neonatal Care 2011; 11: 122-128
  • 23 Jack T, Boehne M, Brent BE , et al. In-line filtration reduces severe complications and length of stay on pediatric intensive care unit: a prospective, randomized, controlled trial. Intensive Care Med 2012; 38: 1008-1016
  • 24 Hemels MA, van den Hoogen A, Verboon-Maciolek MA, Fleer A, Krediet TG. Prevention of neonatal late-onset sepsis associated with the removal of percutaneously inserted central venous catheters in preterm infants. Pediatr Crit Care Med 2011; 12: 445-448
  • 25 Hei MY, Zhang XC, Gao XY , et al. Catheter-related infection and pathogens of umbilical venous catheterization in a neonatal intensive care unit in China. Am J Perinatol 2012; 29: 107-114
  • 26 Bianconi S, Gudavalli M, Sutija VG, Lopez AL, Barillas-Arias L, Ron N. Ranitidine and late-onset sepsis in the neonatal intensive care unit. J Perinat Med 2007; 35: 147-150
  • 27 Terrin G, Passariello A, De Curtis M , et al. Ranitidine is associated with infections, necrotizing enterocolitis, and fatal outcome in newborns. Pediatrics 2012; 129: e40-e45
  • 28 Graham III PL, Begg MD, Larson E, Della-Latta P, Allen A, Saiman L. Risk factors for late onset gram-negative sepsis in low birth weight infants hospitalized in the neonatal intensive care unit. Pediatr Infect Dis J 2006; 25: 113-117
  • 29 Gänzle MG. Reutericyclin: biological activity, mode of action, and potential applications. Appl Microbiol Biotechnol 2004; 64: 326-332
  • 30 Walter J, Britton RA, Roos S. Host-microbial symbiosis in the vertebrate gastrointestinal tract and the Lactobacillus reuteri paradigm. Proc Natl Acad Sci U S A 2011; 108 (Suppl. 01) 4645-4652
  • 31 Ahrne S, Hagslatt ML. Effect of lactobacilli on paracellular permeability in the gut. Nutrients 2011; 3: 104-117
  • 32 Grönlund MM, Arvilommi H, Kero P, Lehtonen OP, Isolauri E. Importance of intestinal colonisation in the maturation of humoral immunity in early infancy: a prospective follow up study of healthy infants aged 0–6 months. Arch Dis Child Fetal Neonatal Ed 2000; 83: F186-F192
  • 33 Deshpande G, Rao S, Patole S, Bulsara M. Updated meta-analysis of probiotics for preventing necrotizing enterocolitis in preterm neonates. Pediatrics 2010; 125: 921-930
  • 34 Alfaleh K, Anabrees J, Bassler D, Al-Kharfi T. Probiotics for prevention of necrotizing enterocolitis in preterm infants. Cochrane Database Syst Rev 2011; (3) CD005496
  • 35 Manzoni P, Mostert M, Leonessa ML , et al. Oral supplementation with Lactobacillus casei subspecies rhamnosus prevents enteric colonization by Candida species in preterm neonates: a randomized study. Clin Infect Dis 2006; 42: 1735-1742
  • 36 Manzoni P, Lista G, Gallo E , et al. Routine Lactobacillus rhamnosus GG administration in VLBW infants: a retrospective, 6-year cohort study. Early Hum Dev 2011; 87 (Suppl. 01) S35-S38
  • 37 Romeo MG, Romeo DM, Trovato L , et al. Role of probiotics in the prevention of the enteric colonization by Candida in preterm newborns: incidence of late-onset sepsis and neurological outcome. J Perinatol 2011; 31: 63-69
  • 38 Kaufman DA, Manzoni P. Strategies to prevent invasive candidal infection in extremely preterm infants. Clin Perinatol 2010; 37: 611-628
  • 39 Manzoni P, Mostert M, Jacqz-Aigrain E, Farina D. The use of fluconazole in neonatal intensive care units. Arch Dis Child 2009; 94: 983-987
  • 40 Sims ME, Yoo Y, You H, Salminen C, Walther FJ. Prophylactic oral nystatin and fungal infections in very-low-birthweight infants. Am J Perinatol 1988; 5: 33-36
  • 41 Ozturk MA, Gunes T, Koklu E, Cetin N, Koc N. Oral nystatin prophylaxis to prevent invasive candidiasis in neonatal intensive care unit. Mycoses 2006; 49: 484-492
  • 42 Ganesan K, Harigopal S, Neal T, Yoxall CW. Prophylactic oral nystatin for preterm babies under 33 weeks' gestation decreases fungal colonisation and invasive fungaemia. Arch Dis Child Fetal Neonatal Ed 2009; 94: F275-F278
  • 43 Howell A, Isaacs D, Halliday R. Australasian Study Group For Neonatal Infections. Oral nystatin prophylaxis and neonatal fungal infections. Arch Dis Child Fetal Neonatal Ed 2009; 94: F429-F433
  • 44 Violaris K, Carbone T, Bateman D, Olawepo O, Doraiswamy B, LaCorte M. Comparison of fluconazole and nystatin oral suspensions for prophylaxis of systemic fungal infection in very low birthweight infants. Am J Perinatol 2010; 27: 73-78
  • 45 Aydemir C, Oguz SS, Dizdar EA , et al. Randomised controlled trial of prophylactic fluconazole versus nystatin for the prevention of fungal colonisation and invasive fungal infection in very low birth weight infants. Arch Dis Child Fetal Neonatal Ed 2011; 96: F164-F168
  • 46 De Carolis MP, Lacerenza S, De Luca D, Bersani I, Costa S, Romagnoli C. Is neonatal antiretroviral therapy a risk factor for NEC occurrence?. Turk J Pediatr 2010; 52: 108-110
  • 47 Manzoni P, Rinaldi M, Cattani S , et al; Italian Task Force for the Study and Prevention of Neonatal Fungal Infections, Italian Society of Neonatology. Bovine lactoferrin supplementation for prevention of late-onset sepsis in very low-birth-weight neonates: a randomized trial. JAMA 2009; 302: 1421-1428
  • 48 Adamkin DH. Mother's milk, feeding strategies, and lactoferrin to prevent necrotizing enterocolitis. JPEN J Parenter Enteral Nutr 2012; 36 (1, Suppl) 25S-29S
  • 49 Manzoni P, Mostert M, Stronati M. Lactoferrin for prevention of neonatal infections. Curr Opin Infect Dis 2011; 24: 177-182
  • 50 Manzoni P, Decembrino L, Stolfi I , et al; Italian Task Force for the Study and Prevention of Neonatal Fungal Infections; Italian Society of Neonatology. Lactoferrin and prevention of late-onset sepsis in the pre-term neonates. Early Hum Dev 2010; 86 (Suppl. 01) 59-61
  • 51 Lupetti A, Brouwer CP, Dogterom-Ballering HE , et al. Release of calcium from intracellular stores and subsequent uptake by mitochondria are essential for the candidacidal activity of an N-terminal peptide of human lactoferrin. J Antimicrob Chemother 2004; 54: 603-608
  • 52 Ward PP, Paz E, Conneely OM. Multifunctional roles of lactoferrin: a critical overview. Cell Mol Life Sci 2005; 62: 2540-2548
  • 53 Manzoni P, Stolfi I, Messner H , et al; Italian Task Force for the Study and Prevention of Neonatal Fungal Infections–the Italian Society of Neonatology. Bovine lactoferrin prevents invasive fungal infections in very low birth weight infants: a randomized controlled trial. Pediatrics 2012; 129: 116-123
  • 54 Cordero L, Ayers LW, Miller RR, Seguin JH, Coley BD. Surveillance of ventilator-associated pneumonia in very-low-birth-weight infants. Am J Infect Control 2002; 30: 32-39
  • 55 Cordero L, Sananes M, Coley B, Hogan M, Gelman M, Ayers LW. Ventilator-associated pneumonia in very low-birth-weight infants at the time of nosocomial bloodstream infection and during airway colonization with Pseudomonas aeruginosa . Am J Infect Control 2000; 28: 333-339
  • 56 Apisarnthanarak A, Holzmann-Pazgal G, Hamvas A, Olsen MA, Fraser VJ. Ventilator-associated pneumonia in extremely preterm neonates in a neonatal intensive care unit: characteristics, risk factors, and outcomes. Pediatrics 2003; 112 (6 Pt 1) 1283-1289
  • 57 Raymond J, Aujard Y. European Study Group. Nosocomial infections in pediatric patients: a European, multicenter prospective study. Infect Control Hosp Epidemiol 2000; 21: 260-263
  • 58 Stover BH, Shulman ST, Bratcher DF, Brady MT, Levine GL, Jarvis WR. Pediatric Prevention Network. Nosocomial infection rates in US children's hospitals' neonatal and pediatric intensive care units. Am J Infect Control 2001; 29: 152-157
  • 59 Garland JS. Strategies to prevent ventilator-associated pneumonia in neonates. Clin Perinatol 2010; 37: 629-643
  • 60 Vendettuoli V, De Cunto A, Tana M , et al. [Pulmonary infections in preterm newborns]. Minerva Pediatr 2007; 59: 97-105
  • 61 Ryan RM, Wilding GE, Wynn RJ, Welliver RC, Holm BA, Leach CL. Effect of enhanced ultraviolet germicidal irradiation in the heating ventilation and air conditioning system on ventilator-associated pneumonia in a neonatal intensive care unit. J Perinatol 2011; 31: 607-614
  • 62 Christensen RD, Henry E, Baer VL , et al. A low-sodium solution for airway care: results of a multicenter trial. Respir Care 2010; 55: 1680-1685
  • 63 Kitajima H, Sumida Y, Tanaka R, Yuki N, Takayama H, Fujimura M. Early administration of Bifidobacterium breve to preterm infants: randomised controlled trial. Arch Dis Child Fetal Neonatal Ed 1997; 76: F101-F107
  • 64 Dani C, Biadaioli R, Bertini G, Martelli E, Rubaltelli FF. Probiotics feeding in prevention of urinary tract infection, bacterial sepsis and necrotizing enterocolitis in preterm infants. A prospective double-blind study. Biol Neonate 2002; 82: 103-108
  • 65 Costalos C, Skouteri V, Gounaris A , et al. Enteral feeding of premature infants with Saccharomyces boulardii . Early Hum Dev 2003; 74: 89-96
  • 66 Bin-Nun A, Bromiker R, Wilschanski M , et al. Oral probiotics prevent necrotizing enterocolitis in very low birth weight neonates. J Pediatr 2005; 147: 192-196
  • 67 Lin HC, Su BH, Chen AC , et al. Oral probiotics reduce the incidence and severity of necrotizing enterocolitis in very low birth weight infants. Pediatrics 2005; 115: 1-4
  • 68 Stratiki Z, Costalos C, Sevastiadou S , et al. The effect of a bifidobacter supplemented bovine milk on intestinal permeability of preterm infants. Early Hum Dev 2007; 83: 575-579
  • 69 Lin HC, Hsu CH, Chen HL , et al. Oral probiotics prevent necrotizing enterocolitis in very low birth weight preterm infants: a multicenter, randomized, controlled trial. Pediatrics 2008; 122: 693-700
  • 70 Samanta M, Sarkar M, Ghosh P, Ghosh J, Sinha M, Chatterjee S. Prophylactic probiotics for prevention of necrotizing enterocolitis in very low birth weight newborns. J Trop Pediatr 2009; 55: 128-131
  • 71 Rougé C, Piloquet H, Butel MJ , et al. Oral supplementation with probiotics in very-low-birth-weight preterm infants: a randomized, double-blind, placebo-controlled trial. Am J Clin Nutr 2009; 89: 1828-1835