Late-onset bloodstream infections of Very-Low-Birth-Weight infants: data from the Polish Neonatology Surveillance Network in 2009-2011

Implementation and long-term efficacy of a multifaceted intervention to reduce central line-associated bloodstream infections in intensive care units of a low-middle-income country

BACKGROUND

Central line-associated bloodstream infections (CLABSIs) pose a significant risk to critically ill patients, particularly in intensive care units (ICU), and are a significant cause of hospital-acquired infections. We investigated whether implementation of a multifaceted intervention was associated with reduced incidence of CLABSIs.

METHODS

This was a prospective cohort study over nine years. We implemented a bundled intervention approach to prevent CLABSIs, consisting of a comprehensive unit-based safety program (CUSP). The program was implemented in the Neonatal ICU, Medical ICU, and Surgical ICU departments at the Aga Khan University Hospital in Pakistan.

RESULTS

The three intervention ICUs combined were associated with an overall 36% reduction in CLABSI rates and a sustained reduction in CLABSI rates for > a year (5 quarters). The Neonatal ICU experienced a decrease of 77% in CLABSI rates lasting ∼1 year (4 quarters). An attendance rate above 88% across all stakeholder groups in each CUSP meeting correlated with a better and more sustained infection reduction.

CONCLUSIONS

Our multifaceted approach using the CUSP model was associated with reduced CLABSI-associated morbidity and mortality in resource-limited settings. Our findings suggest that a higher attendance rate (>85%) at meetings may be necessary to achieve sustained effects post-intervention.

Central-line-associated bloodstream infection burden among Dutch neonatal intensive care units

BACKGROUND

The establishment of an epidemiological overview provides valuable insights needed for the (future) dissemination of infection-prevention initiatives.

AIM

To describe the nationwide epidemiology of central-line-associated bloodstream infections (CLABSI) among Dutch Neonatal Intensive Care Units (NICUs).

METHODS

Data from 2935 neonates born at <32 weeks' gestation and/or with a birth weight <1500 g admitted to all nine Dutch NICUs over a two-year surveillance period (2019-2020) were analysed. Variations in baseline characteristics, CLABSI incidence per 1000 central-line days, pathogen distribution and CLABSI care bundles were evaluated. Multi-variable logistic mixed-modelling was used to identify significant predictors for CLABSI.

RESULTS

A total of 1699 (58%) neonates received a central line, in which 160 CLABSI episodes were recorded. Coagulase-negative staphylococci were the most common infecting organisms of all CLABSI episodes (N=100, 63%). An almost six-fold difference in the CLABSI incidence between participating units was found (2.91-16.14 per 1000 line-days). Logistic mixed-modelling revealed longer central line dwell-time (adjusted odds ratio (aOR):1.08, P<0.001), umbilical lines (aOR:1.85, P=0.03) and single rooms (aOR:3.63, P=0.02) to be significant predictors of CLABSI. Variations in bundle elements included intravenous tubing care and antibiotic prophylaxis.

CONCLUSIONS

CLABSI remains a common problem in preterm infants in The Netherlands, with substantial variation in incidence between centres. Being the largest collection of data on the burden of neonatal CLABSI in The Netherlands, this epidemiological overview provides a solid foundation for the development of a collaborative platform for continuous surveillance, ideally leading to refinement of national evidence-based guidelines. Future efforts should focus on ensuring availability and extraction of routine patient data in aggregated formats.

Late-Onset Sepsis in Very Low Birth Weight Infants

BACKGROUND AND OBJECTIVES

Late-onset sepsis is associated with significant morbidity and mortality among very low birth weight (VLBW) infants. Our objective was to determine risk factors associated with late-onset sepsis and to present temporal trends in overall and pathogen-specific rates.

METHODS

Population-based study by the Israel Neonatal Network on VLBW infants (≤1500 g) born between 1995 and 2019. Late-onset sepsis required clinical symptoms and microbiologic confirmation. Bivariate and multivariable analyses were performed to identify risk factors. The study period was divided into 4 epochs. Overall and pathogen-specific late-onset sepsis rates for each epoch were compared.

RESULTS

The study population comprised 31 612 VLBW infants, of whom 7423 (23.5%) had late-onset sepsis. An increased adjusted risk of late-onset sepsis was associated with gestational age <27 w (odds ratio [OR] 8.90, 95% confidence interval [CI] 7.85-10.09) and delivery room resuscitation (OR 1.43, 95% CI 1.34-1.52) and a decreased adjusted risk among infants born between 2013 and 2019 (OR 0.32, 95% CI 0.29-0.35). Late-onset sepsis rates declined from 29.5% in 1995 to 2000 to 13.0% in 2013 to 2019. Gram-negative and fungal rates decreased in all epochs, whereas gram-positive rates decreased only in the last epoch. The adjusted hazard ratios (95% CI) decreased in the 2013 to 2019 versus 1995 to 2000 epochs and were: all late-onset sepsis, 0.40 (0.37-0.43); gram-positive, 0.47 (0.37-0.59); gram- negative, 0.54 (0.48-0.61); fungal, 0.17 (0.12-0.22).

CONCLUSIONS

The strongest risk factor for late-onset sepsis was gestational age <27 w. Over a 25-year period, the pathogen-specific rates of late-onset sepsis among VLBW infants decreased approximately twofold for gram-positive and gram-negative bacterial infections and sixfold for fungal infections.

Incidence of infant Gram-negative invasive bacterial infections in England, 2011-2019: an observational study using population-wide surveillance data

OBJECTIVE

Invasive bacterial infections account for an estimated 15% of infant deaths worldwide. We aimed to estimate the incidence and trends in invasive bacterial infections in infants caused by Gram-negative pathogens in England during 2011-2019.

METHODS

Laboratory-confirmed invasive bacterial infections in infants (<1 year old) were identified in the UK Health Security Agency national laboratory surveillance data from April 2011 to March 2019. Polymicrobial infections were defined as two or more bacterial species from the same normally sterile sample site. Early-onset infections were defined as <7 days from birth and late-onset as ≥7 days (neonates 7-28 days; infants ≥29 days). Trend analyses were carried out using Poisson (for episodes/incidence) and beta (for proportions) regression.

RESULTS

The annual incidence of invasive bacterial infections increased by 35.9%, from 189.8 to 258.0 cases per 100 000 live births (p<0.001). Late-onset infections in both neonates and infants increased substantially over the study period (p<0.001), whereas early-onset infections increased slightly (p=0.002). Escherichia coli was the most common Gram-negative pathogen isolated and accounted for 27.2% of the overall rise in Gram-negative infant disease incidence. Polymicrobial infections almost doubled, increasing from 29.2 to 57.7 per 100 000 live births (p<0.001), and mostly involved two species (81.3%, 1604/1974 episodes).

CONCLUSIONS

The incidence of Gram-negative invasive bacterial infections in infants increased between 2011/2012 and 2018/2019 in England, driven mainly by an increase in late-onset infections. Further work is required to elucidate the risk factors and drivers of this increased incidence so that opportunities for prevention can be identified.

The Multi-Component Causes of Late Neonatal Sepsis-Can We Regulate Them?

Elucidating the mechanisms of bacterial translocation is crucial for the prevention and treatment of neonatal sepsis. In the present study, we aimed to evaluate the potential of lactoferrin to inhibit the development of late-onset blood infection in neonates. Our investigation evaluates the role of key stress factors leading to the translocation of intestinal bacteria into the bloodstream and, consequently, the development of life-threatening sepsis. Three stress factors, namely weaning, intraperitoneal administration of Gram-positive cocci and oral intake of Gram-negative rods, were found to act synergistically. We developed a novel model of rat pups sepsis induced by bacterial translocation and observed the inhibition of this process by supplementation of various forms of lactoferrin: iron-depleted (apolactoferrin), iron-saturated (hololactoferrin) and manganese-saturated lactoferrin. Additionally, lactoferrin saturated with manganese significantly increases the Lactobacillus bacterial population, which contributes to the fortification of the intestinal barrier and inhibits the translocation phenomenon. The acquired knowledge can be used to limit the development of sepsis in newborns in hospital neonatal intensive care units.

The road to zero nosocomial infections in neonates-a narrative review

Aim

Nosocomial infections (NI) in neonates are associated with prolonged hospitalisation, adverse neurodevelopmental outcome and high mortality. Over the past decade, numerous prevention strategies have resulted in significant reductions in NI rates. In this review, we aim to provide an overview of current NI rates from large, geographically defined cohorts.

Methods

PubMed, Web of Science, EMBASE and Cochrane Library were searched for evidence regarding epidemiology and prevention of NI in neonates. Extracted studies were synthesised in a narrative form with experiential reflection.

Results

Despite the abundance of geographically defined incidence proportions, an epidemiological overview of NI is difficult to provide, given the lack of consensus definition for neonatal NI and different baseline populations being compared. Successful prevention efforts have focused on implementing evidence‐based practices while eliminating outdated strategies. The most promising model for reduction in infection rates is based on quality improvement (QI) collaboratives and benchmarking, involving identification and implementation of best practices, selection of measurable outcomes and fostering a sense of community and transparency.

Conclusion

The preventative rather than curative approach forms the new paradigm for reducing the burden of neonatal infections. Despite progress achieved, continued work towards improved prevention practices is required in the strive towards zero NIs.

Epidemiology and Pathogenesis of Staphylococcus Bloodstream Infections in Humans: a Review

Staphylococci are among the most frequent human microbiota components associated with the high level of bloodstream infection (BSI) episodes. In predisposed patients, there is a high risk of transformation of BSI episodes to sepsis. Both bacterial and host factors are crucial for the outcomes of BSI and sepsis. The highest rates of BSI episodes were reported in Africa, where these infections were up to twice as high as the European rates. However, there remains a great need to analyze African data for comprehensive quantification of staphylococcal BSI prevalence. The lowest rates of BSI exist in Australia. Asian, European, and North American data showed similar frequency values. Worldwide analysis indicated that both Staphylococcus aureus and coagulase-negative staphylococci (CoNS) are the most frequent BSI agents. In the second group, the most prevalent species was Staphylococcus epidermidis, although CoNS were not identified at the species level in many studies. The lack of a significant worldwide decrease in BSI episodes indicates a great need to implement standardized diagnostic methods and research etiological factors using advanced genetic methods.

Coagulase-Negative Staphylococci Contained in Gut Microbiota as a Primary Source of Sepsis in Low- and Very Low Birth Weight Neonates

Background: There are only a few reports in the literature about translocation of coagulase-negative staphylococci (CoNS) as a primary cause of sepsis in neonates, although CoNS are among a short list of “translocating” bacteria when present in abundance. Methods: 468 blood samples, 119 stool samples, and 8 catheter tips, from 311 neonates, were tested for presence of microorganisms. CoNS strains isolated from the blood and stool or from blood and catheter tip of the same newborn at approximately the same time were paired and typed with PFGE (Pulse-Field Gel Electrophoresis) method. The strains were then tested for the presence of adherence genes and biofilm formation. Results: The strains with identical PFGE profiles in comparison to those with non-identical profiles differed in terms of the pattern of the virulence genes and showed a lack of the genes related to adherence, but more often presence of IS256, which is related to virulence. They also were phenotypically unable to adhere to intestinal Caco2 cells. Conclusions: A considerable proportion of CoNS strains isolated from bloodstream of VLBW/LWB neonates was identical to the strains isolated from faeces of the same neonates at the same time. These observations may offer indirect evidence indicating that at least some CoNS can translocate from the gastrointestinal tract of the premature neonates into the bloodstream and thus cause generalized infection.

Neonate Bloodstream Infections in Organization for Economic Cooperation and Development Countries: An Update on Epidemiology and Prevention

The term neonatal sepsis is used to describe a generalized bloodstream infection of bacterial, viral, or fungal origin which is associated with hemodynamic changes and other clinical symptoms and signs, however, there is no unified definition. There are no basic criteria regarding differentiation of early-onset sepsis (EOS) versus late-onset sepsis (LOS). Stratification used in studies on neonatal sepsis also rarely includes the general condition of the newborn according to unambiguous assessment at birth, which hampers the establishment of a clear, uniform epidemiological description of neonatal sepsis. We aim to review the published data about the epidemiology and microbiology of sepsis in Organization for Economic Cooperation and Development (OECD) countries. Data was also collected on sepsis prevention programs that can be implemented in neonatal units. The outcomes of interest were incidence or incidence density of EOS and LOS, microbiology of EOS and LOS, and data on the methodology of the research, in particular the criteria for inclusion and exclusion of newborns from the study. Pubmed, EMBASE, LILACS Embase, Scopus, and Google Scholar were used. For the preselection step, inclusion criteria included: "bloodstream infection" or "neonatal sepsis" (MesH), "very low birth weight", and "country" full-text studies, human, and English language. Exclusion criteria included: studies published in languages other than English and studies available only as an abstracts. For proper selection, inclusion criteria included: information about epidemiology or microbiology bloodstream infection (BSI), study population and case definitions, exclusion criteria, narrative reviews, commentaries, case studies, pilot studies, study protocols, pediatric studies, and only clinical data (without microbiology or epidemiology) or studies with only one etiological factor analysis. The data review indicated the lack of an unequivocal, unified definition and no unambiguous basic criteria with regard to differentiation of EOS versus LOS. Among infants <1500 g, studies reported an EOS rate from 7% to 2%. For studies using other definitions (mostly all inborn babies), the rate of EOS ranged from 1% to 3%. The LOS incidences were much more varied among countries; the highest rates were in the multicenter studies focused on very low birth weight (VLBW) infants. The main pathogens in EOS are GBS and Gram-negative bacteria in LOS. Our review data shows that LOS microbiology is very diverse and that Gram-positive cocci, especially staphylococci, predominate versus Gram-negative rods. Unfortunately, the lack of uniform, international prevention programs results in high newborn morbidity and insufficient postnatal prevention of late-onset infections.

Hospital-acquired Enterobacteriaceae bloodstream infections in children

Among the different age groups of children, newborns are most exposed to hospital-acquired bloodstream infection (HA-BSI), especially those who are burdened with additional risk factors, such as low birth weight, immaturity or exposition to medical procedures. The aim of this study was to analyze the aetiology of HA-BSI among children at high risk, including incidence and drug resistance. The data was obtained from the PubMed database and included medical articles as well as UNICEF and WHO reports published from 2002 to 2017. The study focused on newborns and older children (under 18 years old) with BSI. The main eligibility criteria, apart from age, were Enterobacteriaceae HA-BSI, and the use of invasive medical procedures. It was demonstrated that the main risk factors of infection were age and medical procedures. Due to non-specific symptoms, sepsis is difficult to diagnose, a fact which leads to a high mortality rate in newborns. The existence of such multi-drug resistant strains as Extended-Spectrum β-Lactamases (ESBLs) or Carbapenem-Resistant Enterobacteriaceae (CRE) phenotypes is a grave cause for concern.

Influence of Parenteral Nutrition Delivery Techniques on Growth and Neurodevelopment of Very Low Birth Weight Newborns: A Randomized Trial

Background and Objectives: In very low birth weight (VLBW) newborns, parenteral nutrition (PN) is delivered via a peripheral venous catheter (PVC), a central venous catheter (CVC), or a peripherally inserted central venous catheter (PICC). Up to 45% of PICCs are accompanied by complications, the most common being sepsis. A PVC is an unstable PN delivery technique requiring frequent change. The growth and neurodevelopment of VLBW newborns may be disturbed because of catheters used for early PN delivery and complications thereof. The aim of the conducted study was to evaluate the effect of two PN delivery techniques (PICC and PVC) on anthropometric parameters and neurodevelopment of VLBW newborns. Materials and Methods: A prospective randomized clinical trial was conducted in VLBW (≥750–<1500 g) newborns that met the inclusion criteria and were randomized into two groups: PICC and PVC. We assessed short-term outcomes (i.e., anthropometric parameters from birth until corrected age (CA) 36 weeks) and long-term outcomes (i.e., anthropometric parameters from CA 3 months to 12 months as well as neurodevelopment at CA 12 months according to the Bayley II scale). Results: In total, 108 newborns (57 in the PICC group and 51 in the PVC group) were randomized. Short-term outcomes were assessed in 47 and 38 subjects, and long-term outcomes and neurodevelopment were assessed in 38 and 33 subjects of PICC and PVC groups, respectively. There were no differences observed in anthropometric parameters between the subjects of the two groups in the short- and long-term. Mental development index (MDI) < 85 was observed in 26.3% and 21.2% (p = 0.781), and psychomotor development index (PDI) < 85 was observed in 39.5% and 54.5% (p = 0.239) of PICC and PVC subjects, respectively. Conclusions: In the short- and long-term, no differences were observed in the anthropometric parameters of newborns in both groups. At CA 12 months, there was no difference in neurodevelopment in both groups.

Osmotic stress induces biofilm production by Staphylococcus epidermidis isolates from neonates

Staphylococcus epidermidis is one of the leading causes of bloodstream infections, particularly in premature neonates, and biofilm formation is a major virulence factor. We characterized biofilm formation by 50 S. epidermidis neonatal isolates under osmotic stress and evaluated the expression of biofilm-associated genes. Phenotypical analyses of biofilm production were performed in culture medium with or without addition of NaCl or glucose. In control medium (no additions), most isolates (84%) were nonproducers or weak biofilm producers. Growth in NaCl-containing medium increased the number of moderate/strong producers, and this increase was even greater in medium containing glucose. Most of the protein-enriched biofilms (60%) could be observed only during growth in glucose, whereas 50% of the polysaccharide-enriched biofilms were observed during growth in NaCl. Studies that evaluate the conditions used to characterize biofilm production are important to help us understand the dynamics of this important virulence factor in S. epidermidis and their impact on neonatal infections.

Late-onset sepsis caused by Gram-negative bacteria in very low birth weight infants: a systematic review

INTRODUCTION

Very low birth weight (VLBW) infants are highly susceptible to late-onset sepsis (LOS). Compared to Gram-positive bacteria, Gram-negative bacteria are less common to cause LOS, but are associated with a more severe clinical manifestation, higher mortality, and increased risk of neonatal morbidity. So far, the clinical picture of late-onset Gram-negative sepsis (LOGNS) in VLBW infants has not been elucidated. An up-to-date and thorough understanding of the clinical picture of LOGNS in VLBW infants is important to optimize current anti-sepsis protocols. Areas covered: Literature published in the last three decades was searched for data on the epidemiology, pathogen profile, risk factors, clinical manifestations, laboratory parameters, mortality, and short-term and long-term morbidity of LOGNS in VLBW infants. Expert opinion: Gram-negative bacteria are major contributors of neonatal morbidity and mortality in VLBW infants with LOS, potentially posing a significant disease burden. Unravelling the pathogen-specific clinical picture of LOGNS and the underlying mechanisms is of particular interest. VLBW infants may differ from more mature neonates in terms of disease burden and clinical course of LOGNS. Epidemiologic studies aided by advanced molecular techniques may help to develop anti-sepsis protocols specialized for VLBW infants, with strategies targeting Gram-negative bacteria.

Effects of oral probiotic supplementation on gut Lactobacillus and Bifidobacterium populations and the clinical status of low-birth-weight preterm neonates: a multicenter randomized, double-blind, placebo-controlled trial

Aim

Probiotic bacteria administered directly after birth to preterm neonates may improve gastrointestinal function and may reduce the incidence of late-onset sepsis, which is a frequent complication in this group.

Purpose

The main objective of this study was to evaluate whether a new probiotic bacterial mixture of Lactobacillus rhamnosus KL53A and Bifidobacterium breve PB04 given to preterm, low-birth-weight neonates would influence composition of their gut microbiota and sepsis rates.

Patients and methods

This study was a multicenter, randomized, double-blind, placebo-controlled trial conducted in clinical centers of neonatal care in Poland. A probiotic or placebo preparation was given twice daily to 181 preterm low-birth-weight neonates who were eligible for enteral feeding between July 2012 and July 2013. The probiotic was given to 90 neonates, while placebo was given to 91 neonates. The gut microbiota was monitored by microbiological analysis of stool samples. Sepsis episodes were detected on the basis of clinical and laboratory findings and confirmed by blood cultures.

Results

Tested probiotic administration resulted in continuous increase of the Lactobacillus and Bifidobacterium counts in the gut microbiota. The applied tested strains successfully colonized the neonates gut since they were present in over 90% of stool samples, which was confirmed by molecular analysis. Regardless of the study group (probiotic or placebo), B. breve colonization correlated with lower staphylococcal sepsis incidence, which was irrespective of whether probiotics were given. No sepsis case caused by strains included in study probiotic was recorded.

Conclusion

Appropriately selected and characterized probiotic bacteria may be safely given to preterm neonates to normalize their distorted gut microbiota and may contribute to lower staphylococcal sepsis rates.

Beyond sepsis: Staphylococcus epidermidis is an underestimated but significant contributor to neonatal morbidity

Staphylococcus epidermidis accounts for the majority of cases of neonatal sepsis. Moreover, it has been demonstrated to be associated with neonatal morbidities, such as bronchopulmonary dysplasia (BPD), white matter injury (WMI), necrotizing enterocolitis (NEC) and retinopathy of prematurity (ROP), which affect short-term and long-term neonatal outcome. Imbalanced inflammation has been considered to be a major underlying mechanism of each entity. Conventionally regarded as a harmless commensal on human skin, S. epidermidis has received less attention than its more virulent relative Staphylococcus aureus. Particularities of neonatal innate immunity and nosocomial environmental factors, however, may contribute to the emergence of S. epidermidis as a significant nosocomial pathogen. Neonatal host response to S. epidermidis sepsis has not been fully elucidated. Evidence is emerging regarding the implication of S. epidermidis sepsis in the pathogenesis of neonatal inflammatory diseases. This review focuses on the interplay among S. epidermidis, neonatal innate immunity and inflammation-driven organ injury.

Inflammasome function in monocyte subsets and a risk of late-onset sepsis in preterm very low birth weight neonates

BACKGROUND

Immature immune systems predispose very low birth weight (VLBW) neonates to systemic infections in early life. Defective inflammasome function may increase a neonate's susceptibility to late-onset sepsis (LOS).

METHODS

Blood samples were taken on the 5^th day of life (DOL) for all VLBW neonates (non-LOS and before-LOS groups; N.=76), and within 24 hours of sepsis onset (LOS group; N.=39). Monocyte (MO) subsets and intracellular interleukin-1β (IL-1β) expression were analyzed using flow cytometry. Inflammasome function, defined as level of IL-1β and interleukin-18 (IL-18) was measured with enzyme-linked immunosorbent assay. IRA B cells were reported as a fraction of all B cells.

RESULTS

Stimulation of classical MO in non-LOS cells demonstrated a higher expression of intracellular IL-1β in comparison to MO from before LOS group. Serum from the LOS group revealed a higher level of IL-18. Stimulation of mononuclear cultures from samples taken during LOS resulted in significantly increased supernatant level of IL-1β and IL-18 in comparison to samples taken on 5^th DOL. No changes in the levels of IRA B cells were detected with the onset of sepsis.

CONCLUSIONS

We did not observe a difference in the functioning of the inflammasome within monocytes taken on 5^th DOL from premature VLBW neonates. Furthermore, there was no observable change in the IRA B cells of the septic and non-septic groups. The decreased expression of intracellular IL-1β within classical MO of the before-LOS group may be an independent risk factor for LOS development.

Clinical usefulness of catheter-drawn blood samples and catheter tip cultures for the diagnosis of catheter-related bloodstream infections in neonatology: A systematic review

OBJECTIVES

Neonatal sepsis is the most frequent health care-associated infection in neonatal units. This study aimed to analyze articles on the clinical usefulness of catheter-drawn blood samples and catheter tip cultures for the diagnosis of intravascular catheter-related bloodstream infection (CRBSI) in neonates.

METHODS

A systematic search was performed for studies published from 1987-2017, without language restriction. Observational studies carried out in neonates with CRBSI diagnosed using catheter-drawn blood samples or catheter tip cultures were included.

RESULTS

A total of 412 articles were identified in the databases and 10 articles were included. The 7 studies that evaluated central venous catheter tip cultures and cultures of catheter fragments presented sensitivities ranging from 58.5%-100% and specificities ranging from 60%-95.7%. Three studies that evaluated catheter-drawn blood cultures, paired with peripheral blood cultures, reported sensitivity and specificity of 94% and 71% when evaluated for the differential time to positivity. When quantitative evaluation was performed, the sensitivity and specificity were 80% and 99.4%.

CONCLUSIONS

Most of the studies analyzed cultures from the central venous catheter tip and catheter fragments for the diagnosis of CRBSI in neonatal populations. The results of this review suggest that the analysis of the catheter-drawn blood samples and catheter tip cultures, paired with peripheral blood cultures, are efficient methods for the diagnosis of CRBSI in neonates.

Infections following surgical patent ductus arteriosus ligation in very-low-birthweight neonates

BACKGROUND

Very-low-birthweight (VLBW) neonates (<1500g) comprise approximately 1% of liveborn infants in Poland. Patent ductus arteriosus (PDA) is a common complication of prematurity. This study aimed to determine how many VLBW neonates treated in the participating units needed surgical correction of PDA, and to evaluate the incidence of various types of postoperative infections and their microbiology.

METHODS

Observational study in five neonatology departments by the Polish Neonatology Surveillance Network, involving 2039 VLBW newborns of whom 103 (5.1%) required surgical PDA ligation. Continuous infection surveillance was conducted between 2009 and 2013; infections were defined based on Gastmeier's criteria.

RESULTS

PDA surgery was required significantly more frequently in infants from multiple pregnancies, and where labour was complicated by amnionitis. Surgical PDA correction was performed, on average, at 19 days of life. The incidence of infection was 48.5% (N = 50), and the most common infections were bloodstream infection (26.2%) and pneumonia (22.3%). A correlation was observed between the day on which the procedure was performed and the time of infection: the earlier the neonate underwent PDA surgery, the earlier the infection manifested (P = 0.032). A high CRIB score and chorioamnionitis contributed significantly to the presence of infection.

CONCLUSION

The later the PDA surgery was performed, the later the infection occurred. The incidence of infection after correction of PDA among VLBW neonates was comparable with the incidence of infection among all hospitalized VLBW neonates.

Antibiotic consumption in laboratory confirmed vs. non-confirmed bloodstream infections among very low birth weight neonates in Poland

BACKGROUND

Newborns are a population in which antibiotic consumption is extremely high. Targeted antibiotic therapy should help to reduce antibiotics consumption. The aim of this study was an assessment of antibiotic usage in bloodstream infections treatment in the Polish Neonatology Surveillance Network (PNSN) and determining the possibility of applying this kind of data in infection control, especially for the evaluation of standard methods of microbiological diagnostics.

METHODS

Data were collected between 01.01.2009 and 31.12.2013 in five teaching NICUs from the PNSN. The duration of treatment in days (DOT) and the defined daily doses (DDD) were used for the assessment of antibiotics consumption.

RESULTS

The median DOT for a single case of BSI amounted to 8.0 days; whereas the median consumption expressed in DDD was 0.130. In the case of laboratory confirmed BSI, median DOT was 8 days, and consumption-0.120 DDD. Median length of therapy was shorter for unconfirmed cases: 7 days, while the consumption of antibiotics was higher-0.140 DDD (p < 0.0001). High consumption of glycopeptides expressed in DOTs was observed in studied population, taking into account etiology of infection.

CONCLUSIONS

Even application of classical methods of microbiological diagnostics significantly reduces the consumption of antibiotics expressed by DDD. However, the high consumption of glycopeptides indicates the necessity of applying rapid diagnostic assays. Nevertheless, the assessment of antibiotic consumption in neonatal units represents a methodological challenge and requires the use of different measurement tools.

Efficacy of periodic surveillance culture in a neonatal intensive care unit in the presumption of causative pathogens of late-onset bacterial infection

BACKGROUND

Surveillance cultures have been recommended for infection control of resistant bacteria in neonatal intensive care units (NICUs). However, the utility of surveillance cultures in the presumption of causative bacteria in late-onset bacterial infection has been controversial. The aim of the present study was to investigate the relationship between the causative pathogens of late-onset bacterial infection and the results of periodic surveillance cultures in a NICU.

METHODS

A retrospective study was performed on 600 patients hospitalized in the NICU of a large metropolitan hospital from 2010-2013. The correspondence of the results of surveillance cultures with causative pathogens was analyzed in patients who developed late-onset bacterial infection.

RESULTS

Staphylococcus species and enterobacterium were the most prevalent in the samples obtained from the oropharynx and rectum, respectively, during the investigation period. Twenty patients (3.3%) developed late-onset bacterial infection. The causative pathogens in 15 patients (75%) were also detected from the final surveillance cultures; these patients tended to be older than the other 5 patients (P = .003).

CONCLUSIONS

Surveillance cultures might be useful for the presumption of causative pathogens of late-onset bacterial infection in patients with risk factors for the development of nosocomial bacterial infection.

Clonal Structure and Characterization of Staphylococcus aureus Strains from Invasive Infections in Paediatric Patients from South Poland: Association between Age, spa Types, Clonal Complexes, and Genetic Markers

The aim of current study was to examine clonal structure and genetic profile of invasive Staphylococcus aureus isolates recovered from infants and children treated at the Jagiellonian University Children’s Hospital of Krakow, Poland. The 107 invasive S. aureus isolates, collected between February 2012 and August 2014, were analysed retrospectively. Antimicrobial susceptibility testing, spa typing and DNA microarray analysis were performed to determine clonal distribution, diversity and gene content in regard to patients characteristics. In total, 107 isolates were recovered from 88 patients with clinical symptoms of invasive bacterial infection. The final set of 92 non-duplicate samples included 38 MRSA isolates. Additionally, a set of 54 S. aureus isolates collected during epidemiological screening was genotyped and analysed. There were 72 healthcare-associated (HCA) and 20 community-onset (CO) infection events caused by 33 and 5 MRSA isolates, respectively. The majority of isolates were affiliated with the major European clonal complexes CC5 (t003, spa-CC 002), CC45 (spa-CC 015), CC7 or CC15 (t084, t091, spa-CC 084). Two epidemic clones (CC5-MRSA-II or CC45-MRSA-IV) dominated among MRSA isolates, while MSSA population contained 15 different CCs. The epidemiological screening isolates belonged to similar genetic lineages as those collected from invasive infection cases. The HCA infection events, spa types t003, t2642 or CC5 were significantly associated with infections occurring in neonates and children under 5 years of age. Moreover, carriage of several genetic markers, including erm(A), sea (N315), egc-cluster, chp was significantly higher in isolates obtained from children in this age group. The spa types t091 and t008 were underrepresented among patients aged 5 years or younger, whereas spa type t008, CC8 and presence of splE was associated with infection in children aged 10 years or older. The HCA-MRSA strains were most frequently found in children under 5 years, although the majority of invasive infections was associated with MSSA strains. Moreover, an association between age group of children from the study population and a specific strain genotype (spa type, clonal complex or genetic content) was observed among the patients.

Blood Culture Proven Early Onset Sepsis and Late Onset Sepsis in Very-Low-Birth-Weight Infants in Korea

Neonatal sepsis remains one of the most important causes of death and co-morbidity in very-low-birth-weight (VLBW) infants. The aim of this study was to determine the current incidences of early-onset sepsis (EOS) and late-onset sepsis (LOS), the distribution of pathogens, and the impact of infection on co-morbidities in VLBW infants. We analyzed the data including sepsis episode from 2,386 VLBW infants enrolled in Korean Neonatal Network from January 2013 to June 2014. We defined EOS as a positive blood culture occurring between birth and 7 days of life and LOS after 7 days of life. Sepsis was found in 21.1% of VLBW infants. The risk of sepsis was inversely related to birth weight and gestational age. EOS was found in only 3.6% of VLBW infants, however the mortality rate was as high as 34.1%. EOS was associated with the increased odds for bronchopulmonary dysplasia and intraventricular hemorrhage. The vast majority of EOS was caused by Gram-positive organisms, particularly coagulase-negative staphylococci (30.6%). LOS developed in 19.4% of VLBW infants with a 16.1% mortality rate. Pathogens in LOS were dominated by coagulase-negative staphylococci (38.3%). Twenty-five percent and fifty percent of first LOS episode occurred after 12 days and 20 days from birth, respectively. Younger and smaller VLBW infants showed the earlier occurrence day for the 25% of first LOS episode. This study provides a recent nationwide epidemiology of sepsis in VLBW infants in Korea. Based on this study, successful strategies to reduce infections would improve survival and reduce morbidity.

Infections and risk-adjusted length of stay and hospital mortality in Polish Neonatology Intensive Care Units

BACKGROUND

The objectives of this study were to analyze the impact of infections on prolonging hospital stay with consideration of underlying risk factors and determining the mortality rates and its association with infections.

METHODS

An electronic database developed from a continuous prospective targeted infection surveillance program was used in the study. Data were collected from 2009 to 2012 in five Polish tertiary academic neonatal intensive care units (NICUs). The length of stay (LOS) of 2,003 very low birth weight (VLBW) neonates was calculated as the sum of the number of days since birth until death or until reaching a weight of 1,800g.

RESULTS

The median LOS for neonates with infections was twice as high as for neonates without infection. LOS was significantly affected by the overall general condition of the neonate, as expressed by both gestational age and birth weight as well as by the Clinical Risk Index for Babies (CRIB) score; another independent factor was presence of at least one infection. Risk of in-hospital mortality was significantly increased by male sex and vaginal birth and was lower among breastfed neonates. Deaths were significantly more frequent in neonates without infection.

CONCLUSIONS

The general condition of VLBW infants statistically increase both their risk of mortality and LOS; this is in contrast to the presence of infection, which significantly prolonged LOS only.

Human parechovirus infection in neonatal intensive care

BACKGROUND

Approximately 5-6% of all infective episodes in neonatal intensive care unit (NICU) are of viral origin. Previous studies suggest that human parechovirus (HPeV) infection presents most commonly in term infants, as a sepsis-like syndrome in which meningoencephalitis is prominent. Our aim was to study the infection rate and associated features of HPeV.

METHODS

Blood samples were taken from NICU babies older than 48 hours, who were being investigated for late onset sepsis. Clinical and laboratory data were collected at the time of the suspected sepsis episode. Samples were tested using universal primers and probe directed at the 5'-untranslated region of the HPeV genome by reverse transcriptase polymerase chain reaction (RT-PCR). Results were confirmed by electrophoresis and DNA sequencing.

RESULTS

HPeV was detected in 11 of 84 samples (13%). These infants had a mean [interquartile range (IQR)] gestational age of 28.9 (26.9-30.6) weeks and mean birth weight of 1.26 (SD = 0.72) kg. The median day of presentation was 16 (IQR: 11-27). These characteristics were similar to the infants without positive viral detection. Six infants presented with respiratory signs. One infant presented with signs of meningitis. Six of the 11 episodes of HPeV infection occurred during the winter months (December to February). No HPeV positive infants had abnormal findings on their 28-day cranial ultrasound examination.

CONCLUSIONS

We found an HPeV infection rate of 13% in infants being tested for late onset sepsis. HPeV should be considered as a possible cause of sepsis-like symptoms in preterm infants.