The relationship between Gram-negative colonization and bloodstream infections in neonates: a systematic review and meta-analysis

Safety and efficacy of phage application in bacterial decolonisation: a systematic review

Colonisation by bacterial pathogens typically precedes invasive infection and seeds transmission. Thus, effective decolonisation strategies are urgently needed. The literature reports attempts to use phages for decolonisation. To assess the in-vivo efficacy and safety of phages for bacterial decolonisation, we performed a systematic review by identifying relevant studies to assess the in-vivo efficacy and safety of phages for bacterial decolonisation. We searched PubMed, Embase (Ovid), MEDLINE (Ovid), Web of Science, and the Cochrane Library to identify relevant articles published between Jan 1, 1990, and May 12, 2023, without language restrictions. We included studies that assessed the efficacy of phage for bacterial decolonisation in humans or vertebrate animal models. This systematic review is registered with PROSPERO, CRD42023457637. We identified 6694 articles, of which 56 (51 animal studies and five clinical reports) met the predetermined selection criteria and were included in the final analysis. The gastrointestinal tract (n=49, 88%) was the most studied bacterial colonisation site, and other sites were central venous catheters, lung, nose, skin, and urinary tract. Of the 56 included studies, the bacterial load at the colonisation site was reported to decrease significantly in 45 (80%) studies, but only five described eradication of the target bacteria. 15 studies reported the safety of phages for decolonisation. No obvious adverse events were reported in both the short-term and long-term observation period. Given the increasing life-threatening risks posed by bacteria that are difficult to treat, phages could be an alternative option for bacterial decolonisation, although further optimisation is required before their application to meet clinical needs.

A clinical predictive model for pre-transplantation Klebsiella pneumoniae colonization and relevance for clinical outcomes in patients receiving allogeneic hematopoietic stem cell transplantation

The purpose of this study is to establish a clinical prediction model to discriminate patients at high risk of Klebsiella pneumoniae (KP) colonization before allogeneic hematopoietic stem cell transplantation (allo-HSCT) and evaluate the impact of KP colonization on clinical outcomes after allo-HSCT. We retrospectively collected data from 2,157 consecutive patients receiving allo-HSCT between January 2018 and March 2022. KP colonization was defined as a positive test for KP from a pharyngeal or anal swab before allo-HSCT. Logistic regression was used to build a clinical prediction model. Cox regression analyses were performed to explore the effect of KP colonization on clinical outcomes. Among all the inpatients, 166 patients had KP colonization and 581 with no positive pathogenic finding before transplantation. Seven candidate predictors were entered into the final prediction model. The prediction model had an area under the curve of 0.775 (95% CI 0.723-0.828) in the derivation cohort and 0.846 (95% CI: 0.790-0.902) in the validation cohort. Statistically significantly different incidence rates were observed among patient groups with clinically predicted low, medium, and high risk for KP infection (P < 0.001). The presence of KP colonization delayed platelet engraftment (P < 0.001) and patients with KP colonization were more likely to develop KP bloodstream infections within 100 days after allo-HSCT (P < 0.0001). Patients with KP colonization had higher non-relapse mortality (P = 0.032), worse progression-free survival (P = 0.0027), and worse overall survival within 100 days after allo-HSCT (P = 0.013). Our findings suggest that increased awareness of risks associated with pre-transplantation bacterial colonization is warranted.IMPORTANCESeveral studies have identified that Klebsiella pneumoniae (KP) is among the most common and deadly pathogens for patients in hospital intensive care units and those receiving transplantation. However, there are currently no studies that evaluate the impact of KP colonization to patients undergoing allogeneic hematopoietic stem cell transplantation. Our results confirm that pre-existing KP colonization is relatively common in a hematology transplant ward setting and negatively affects post-transplantation prognosis. Our clinical prediction model for KP colonization can support early intervention in patients at high risk to avoid subsequent bloodstream infections and improve survival outcomes. Altogether, our data suggest that increased awareness of risks associated with pre-transplantation bacterial colonization is warranted. Future studies are needed to confirm these findings and to test early intervention strategies for patients at risk of complications from KP infection.

Perinatal colonization with extended-spectrum beta-lactamase-producing and carbapenem-resistant Gram-negative bacteria: a hospital-based cohort study

BACKGROUND

Antimicrobial resistance (AMR) is a growing global health threat that contributes to substantial neonatal mortality. Bangladesh has reported some of the highest rates of AMR among bacteria causing neonatal sepsis. As AMR colonization among newborns can predispose to infection with these bacteria, we aimed to characterize the frequency of and risk factors for colonization of mothers and newborns during hospitalization for delivery.

METHODS

We enrolled pregnant women presenting for delivery to a tertiary care hospital in Faridpur, Bangladesh. We collected vaginal and rectal swabs from mothers pre- and post-delivery, rectal swabs from newborns, and swabs from the hospital environment. Swabs were plated on agars selective for extended-spectrum-beta-lactamase producing bacteria (ESBL-PB) and carbapenem-resistant bacteria (CRB). We performed logistic regression to determine factors associated with ESBL-PB/CRB colonization.

RESULTS

We enrolled 177 women and their newborns during February-October 2020. Prior to delivery, 77% of mothers were colonized with ESBL-PB and 15% with CRB. 79% of women underwent cesarean deliveries (C-section). 98% of women received antibiotics. Following delivery, 98% of mothers and 89% of newborns were colonized with ESBL-PB and 89% of mothers and 72% of newborns with CRB. Of 290 environmental samples, 77% were positive for ESBL-PB and 69% for CRB. Maternal pre-delivery colonization was associated with hospitalization during pregnancy (RR for ESBL-PB 1.24, 95% CI 1.10-1.40; CRB 2.46, 95% CI 1.39-4.37). Maternal post-delivery and newborn colonization were associated with C-section (RR for maternal CRB 1.31, 95% CI 1.08-1.59; newborn ESBL-PB 1.34, 95% CI 1.09-1.64; newborn CRB 1.73, 95% CI 1.20-2.47).

CONCLUSIONS

In this study, we observed high rates of colonization with ESBL-PB/CRB among mothers and newborns, with pre-delivery colonization linked to prior healthcare exposure. Our results demonstrate this trend may be driven by intense use of antibiotics, frequent C-sections, and a contaminated hospital environment. These findings highlight that greater attention should be given to the use of perinatal antibiotics, improved surgical stewardship for C-sections, and infection prevention practices in healthcare settings to reduce the high prevalence of colonization with AMR organisms.

Gut colonization and subsequent infection of neonates caused by extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae

The gut microbiota harbors diverse bacteria considered reservoirs for antimicrobial resistance genes. The global emergence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales (ESBL-PE) significantly contributes to healthcare-associated infections (HAIs). We investigated the presence of ESBL-producing Escherichia coli (ESBL-PEco) and ESBL-producing Klebsiella pneumoniae (ESBL-PKpn) in neonatal patients' guts. Furthermore, we identified the factors contributing to the transition towards ESBL-PEco and ESBL-PKpn-associated healthcare-associated infections (HAIs). The study was conducted from August 2019 to February 2020, in a Neonatal Intensive Care Unit of the Hospital Infantil de México Federico Gómez. Rectal samples were obtained upon admission, on a weekly basis for a month, and then biweekly until discharge from the neonatology ward. Clinical data, culture results, and infection information were gathered. We conducted antimicrobial tests, multiplex PCR assay, and pulsed-field gel electrophoresis (PFGE) to determine the antimicrobial resistance profile and genetic relationships. A comparison between the group's controls and cases was performed using the Wilcoxon and Student t-tests. Of the 61 patients enrolled, 47 were included, and 203 rectal samples were collected, identifying 242 isolates. In 41/47 (87%) patients, colonization was due to ESBL-PEco or ESBL-PKpn. And nine of them developed HAIs (22%, 9/41). ESBL-PEco resistance to cephalosporins ranged from 25.4% to 100%, while ESBL-PKpn resistance varied from 3% to 99%, and both bacteria were susceptible to carbapenems, tigecillin, and colistin. The prevalent bla CTX-M-group-1 gene accounted for 77.2% in ESBL-PEco and 82.2% in ESBL-PKpn, followed by bla TEM 50% and bla OXA-1 43.8% in ESBL-PEco and bla TEM 80.2% and bla SHV 76.2% in ESBL-PKpn. Analysis of clonality revealed identical colonizing and infection isolates in only seven patients. Significant risk factors included hospital stay duration, duration of antibiotic treatment, and invasive device usage. Our findings suggest high ESBL-PEco and ESBL-PKpn rates of colonization often lead to infection in neonates. Attention should be paid to patients with ESBL-PE.

Impact of intestinal colonization by Gram-negative bacteria on the incidence of bloodstream infections and lethality in critically ill neonates

BACKGROUND

Early detection of antimicrobial-resistant microorganisms is crucial to prevent subsequent invasive infections and contain their spread in the Neonatal Intensive Care Unit (NICU). This study aims to investigate the association between intestinal colonization (IC) by Gram-negative bacteria and the risk of bloodstream infection (BSI) in critically ill neonates.

METHODS

Data from the electronic medical records of 678 newborns admitted to a NICU Brazilian between 2018 and 2022 were retrospectively analyzed. Participants were monitored by the National Health Security Network.

RESULTS

Among neonates, 6.9 % had IC (56.9 % attributed to Acinetobacter baumannii); of these, 19.1 % developed BSI (66.7 % by Staphylococcus spp.). Within the A. baumannii colonization, 34.5 % occurred during an outbreak in September 2021. Colonized individuals had a longer mean length of stay (49.3 ± 26.4 days) and higher mortality rate (12.8 %) compared to non-colonized individuals (22.2 ± 16.9 days; 6.7 %, respectively). Previous use of antimicrobials and invasive devices significantly increased the risk of colonization. Colonization by drug-resistant microorganisms, along with the occurrence of BSI, was associated with increased mortality and reduced survival time.

CONCLUSIONS

IC contributed to the incidence of BSI, leading to more extended hospital stays and higher mortality rates. Its early detection proved to be essential to identify an outbreak and control the spread of resistant microorganisms within the NICU.

Burden of antibiotic resistance in infections among very-low-birthweight infants in Singapore

Introduction

Recent reports have described the increasing predominance of Gram-negative organisms among invasive bacterial infections affecting preterm infants. This changing pattern of infections is concerning due to the spread of antibiotic resistance among Gram-negatives.

Method

We conducted a single-centre, retrospective cohort study involving very-low-birthweight (VLBW) (<1500 grams) infants born <32 weeks gestation, with culture-proven infections (blood, urine, cerebrospinal fluid [CSF]) in the neonatal intensive care unit from 1 January 2005 to 31 October 2017.

Results

A total of 278 out of 2431 (11.4%) VLBW infants born <32 weeks gestation developed 334 infections, i.e. 52 (15.6%) early-onset infections (EOIs) and 282 (84.4%) late-onset infections (LOIs). The overall incidence decreased from 247 to 68 infections per 1000 infants over the study period, corresponding to reductions in LOI (211 to 62 infections per 1000 infants). A total of 378 bacteria were isolated, i.e. Gram-negatives accounted for 70.9% (45 of 59 [76.3%] EOI; 223 of 319 [69.9%] LOI). Specific resistant organisms were noted, i.e. Methicillin-resistant Staphylococcus aureus (8 of 21 S. aureus infections [38.1%]); Cephalosporin-resistant Klebsiella (18 of 62 isolates [29.0%]) and multidrug-resistant [MDR] Acinetobacter (10 of 27 isolates [37.0%]). MDR organisms accounted for 85 of 195 (43.6%) Gram-negative infections from the bloodstream and CSF. Based on laboratory susceptibility testing, only 63.5% and 49.3% of infecting bacteria isolated in blood were susceptible to empiric antibiotic regimens used for suspected EOI and LOI, respectively.

Conclusion

Gram-negative bacteria are the predominant causative organisms for EOI and LOI and are frequently MDR. Understanding the pattern of antimicrobial resistance is important in providing appropriate empiric coverage for neonatal infections.

Acquisition and carriage of genetically diverse multi-drug resistant gram-negative bacilli in hospitalised newborns in The Gambia

BACKGROUND

This detailed genomic study characterised multi-drug resistant-Gram negative bacilli (MDR-GNB) carriage in neonates < 2 kg and paired mothers at a low-resource African hospital.

METHODS

This cross-sectional cohort study was conducted at the neonatal referral unit in The Gambia with weekly neonatal skin and peri-anal sampling and paired maternal recto-vaginal swabs. Prospective bacteriological culture used MacConkey agar with species identification by API20E and API20NE. All GNB isolates underwent whole genome sequencing on Illumina Miseq platform. Multi-Locus Sequence Typing and SNP-distance analysis identified strain type and relatedness.

RESULTS

135 swabs from 34 neonates and 21 paired mothers, yielded 137 GNB isolates, of which 112 are high quality de novo assemblies. Neonatal MDR-GNB carriage prevalence is 41% (14/34) at admission with 85% (11/13) new acquisition by 7d. Multiple MDR and ESBL-GNB species are carried at different timepoints, most frequently K. pneumoniae and E. coli, with heterogeneous strain diversity and no evidence of clonality. 111 distinct antibiotic resistance genes are mostly beta lactamases (Bla-AMPH, Bla-PBP, CTX-M-15, Bla-TEM-105). 76% (16/21) and 62% (13/21) of mothers have recto-vaginal carriage of ≥1 MDR-GNB and ESBL-GNB respectively, mostly MDR-E. coli (76%, 16/21) and MDR-K. pneumoniae (24%, 5/21). Of 21 newborn-mother dyads, only one have genetically identical isolates (E. coli ST131 and K. pneumoniae ST3476).

CONCLUSIONS

Gambian hospitalised neonates exhibit high MDR and ESBL-GNB carriage prevalence with acquisition between birth and 7d with limited evidence supporting mother to neonate transmission. Genomic studies in similar settings are required to further understand transmission and inform targeted surveillance and infection prevention policies.

Should Perirectal Swab Culture Be Performed in Cases Admitted to the Neonatal Intensive Care Unit? Lessons Learned from the Neonatal Intensive Care Unit

Serial perirectal swabs are used to identify colonization of multidrug-resistant bacteria and prevent spread. The purpose of this study was to determine colonization with carbapenem-resistant Enterobacterales (CRE) and vancomycin-resistant Enterococci (VRE). An additional purpose was to establish whether sepsis and epidemic associated with these factors were present in the neonatal intensive care unit (NICU), to which infants with hospital stays exceeding 48 h in an external healthcare center NICU were admitted. Perirectal swab samples were collected in the first 24 h by a trained infection nurse using sterile cotton swabs moistened with 0.9% NaCl from patients admitted to our unit after hospitalization exceeding 48 h in an external center. The primary outcome was positivity in perirectal swab cultures, and the secondary outcomes were whether this caused invasive infection and significant NICU outbreaks. A total of 125 newborns meeting the study criteria referred from external healthcare centers between January 2018 and January 2022 were enrolled. Analysis revealed that CRE constituted 27.2% of perirectal swab positivity and VRE 4.8%, and that one in every 4.4 infants included in the study exhibited perirectal swab positivity. The detection of colonization by these microorganisms, and including them within the scope of surveillance, is an important factor in the prevention of NICU epidemics.

Evaluating the Use of Neonatal Colonization Screening for Empiric Antibiotic Therapy of Sepsis and Pneumonia

(1) Background: Since 2013, weekly screening for multidrug-resistant Gram-negative (MDRGN) bacteria has been performed in German neonatal intensive care units (NICU). National guidelines recommend considering these colonization analyses for antibiotic treatment regimens. Our retrospective single center study provides insight into the clinical dichotomy of bacterial colonization and infection rates in neonates. (2) Methods: We analyzed microbiological data of neonates admitted to our tertiary level NICU over nine years. Colonization with MDRGN/Serratia marcescens (SERMA) was compared to microbiological findings in sepsis and pneumonia. (3) Results: We analyzed 917 blood and 1799 tracheal aspirate samples. After applying criteria from the Nosocomial Infection Surveillance for Neonates (NEO-KISS), we included 52 and 55 cases of sepsis and pneumonia, respectively; 19.2% of sepsis patients and 34.5% of pneumonia patients had a prior colonization with MDRGN bacteria or SERMA. In these patients, sepsis was not attributable to MDRGN bacteria yet one SERMA, while in pneumonias, ten MDRGN bacteria and one SERMA were identified. We identified late-onset pneumonia and cesarean section as risk factors for MDRGN/SERMA acquisition. (4) Conclusions: Colonization screening is a useful tool for hygiene surveillance. However, our data suggest that consideration of colonization with MDRGN/SERMA might promote extensive use of last resort antibiotics in neonates.

Perinatal bacterial colonization and neonatal early-onset sepsis: A case-control study

BACKGROUND

The utility of determining maternal-neonatal surface colonization as detected by standard microbiological cultures around the time of birth is unclear. The aim of this study is to evaluate the association between maternal and neonatal surface colonization at birth and neonatal early onset sepsis (EOS).

OBJECTIVE

To investigate the association of white matter hyperintensities (WMHs) present in the brain with AD CSF biomarker levels.

METHODS

We conducted a case-control study of newborns admitted to the neonatal department of a referral women's and children's hospital from 2009 to 2017. Cases were infants with blood-culture-confirmed EOS (<3 days of life), and controls were infants without EOS randomly chosen based on the cases' date of birth. Maternal genitourinary and neonatal ear swab cultures were used to determine bacterial surface colonization status.

RESULTS

Fifty-one infants were diagnosed with EOS during the study period, where Escherichia coli (45%), and Group B Streptococcus (23%) accounted for 68% of infecting organisms. Compared to infants without EOS, those infected were more likely to have surface colonization of the mothers (60% vs 40%, p = 0.048) and infants (90% vs 11%, p < 0.001). In univariate analysis, chorioamnionitis [7.1 (95% CI 2.9, 16.8)], small-for-gestational-age [OR 0.08 (95% CI 0.02, 0.4)], exposure to antibiotics around time of birth [2.3 (95% CI 1.0, 5.1)], maternal surface colonization [2.2 (95% CI 1.0, 4.9)] and neonatal surface colonization [23.5 (95% CI 7.3, 76.1)] were significantly associated with EOS. Adjusting for potential confounders, neonatal colonization remained significantly associated with neonatal EOS [AOR 15.0 (95% CI 3.5, 64.2), p < 0.001].

CONCLUSION

In our setting with predominant Gram-negative EOS, neonatal colonization but not maternal colonization was significantly associated with EOS in the newborn.

Successful Control of an Outbreak by Phenotypically Identified Extended-Spectrum Beta-Lactamase–Producing Klebsiella pneumoniae in a Neonatal Intensive Care Unit

Background: Premature newborns represent a vulnerable population, at high risk of acquiring nosocomial infections during neonatal intensive care unit (NICU) admission. Multidrug-resistant organisms represent the greatest concern due to their intrinsic virulence and the limited therapeutic options. Resistant Enterobacterales are a growing threat for critically ill neonates, with increasing numbers of NICU outbreaks caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales being described. This study reports the early detection and successful control of an outbreak caused by ESBL-producing Klebsiella pneumoniae (ESBL-KP) in an Italian NICU in February 2021. Results: A total of 13 newborns tested positive for ESBL-KP between 2–9 February 2021, of whom four (31%) had a bloodstream infection. Two were critically ill, extremely premature newborns who died because of multiple comorbidities, and two were cured after treatment with meropenem. All other patients survived and were either discharged home or moved to other hospitals/wards in good clinical condition. ESBL-KP ST45 was found in all isolates by multilocus sequence typing (MLST) analysis. An outbreak control plan was set, including surveillance cultures for all neonates, NICU environments, and medical devices, along with the extended use of contact precautions and cohorting. In addition, the infection control plan was carried out through reinforcement and enhancement measures to guarantee maximal compliance. The outbreak was successfully controlled in seven days, given that no further cases were identified after 9 February. The source of the ESBL-KP outbreak was not identified through environmental sampling. Conclusions: Thanks to multidisciplinary management, a threatening outbreak of ESBL-KP in a NICU was controlled in few days. The prompt recognition of the event onset and the adoption of infection control interventions helped contain the bacteria spread on the ward.

ESBL Escherichia coli Isolates Have Enhanced Gut Colonization Capacity Compared to Non-ESBL Strains in Neonatal Mice

Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli can cause invasive infections in infants and immunocompromised children with high associated morbidity and mortality. The gut is a major reservoir of these strains in the community. Current dogma dictates that antimicrobial resistance is associated with a fitness cost. However, recent data show that some contemporary ESBL E. coli strains may be more "fit" compared to nonresistant E. coli strains. Here, we use whole-genome sequencing to first characterize 15 ESBL E. coli strains isolated from infants in a Pakistani community, a clinical extraintestinal pathogenic ESBL E. coli ST131 strain, and a non-ESBL commensal E. coli strain, and then use a novel animal model of early life gut colonization to assess the ability of these strains to colonize the infant mouse gut. We determined that CTX-M-15 was present in all the ESBL strains, as well as additional beta-lactamases and genes conferring resistance to multiple antibiotic classes. In the animal model, 11/16 ESBL E. coli strains had significantly higher burden of colonization at week four of life compared to commensal strains, even in the absence of selective antibiotic pressure, suggesting that these strains may have enhanced fitness despite being highly antimicrobial resistant. IMPORTANCE Antimicrobial resistance is a global public health emergency. Infants, especially preterm infants and those in the neonatal intensive care unit, immunocompromised hosts, and those with chronic illnesses are at highest risk of adverse outcomes from invasive infections with antimicrobial-resistant strains. It has long been thought that resistance is associated with a fitness cost, i.e., antimicrobial-resistant strains are not able to colonize the gut as well as nonresistant strains, and that antibiotic exposure is a key risk factor for persistent colonization with resistant strains. Here, we use a novel infant mouse model to add to the growing body of literature that some highly-resistant contemporary Escherichia coli strains can persist in the gut with a significant burden of colonization despite absence of antibiotic exposure.

The hospital environment versus carriage: transmission pathways for third-generation cephalosporin-resistant bacteria in blood in neonates in a low-resource country healthcare setting

Neonatal bloodstream infections (BSI) can lead to sepsis, with high morbidity and mortality, particularly in low-income settings. The high prevalence of third-generation cephalosporin-resistant organisms (3GC-RO) complicates the management of BSI. Whether BSI is linked to carriage of 3GC-RO, or to acquisition from the hospital environment is important for infection prevention and control, but the relationship remains unclear, especially in low-income settings. At a tertiary hospital in Mwanza, Tanzania, we screened neonatal blood and rectal samples from 200 neonates, and 400 (hospital) environmental samples. We used logistic regression to identify risk factors, and Kolmogorov–Smirnov tests and randomisation analyses to compare distributions of species and resistance patterns to assess potential routes of transmission. We found that BSIs caused by 3GC-RO were frequent (of 59 cases of BSI, 55 were caused by 3GC-RO), as was carriage of 3GC-RO, particularly Escherichia coli, Klebsiella pneumoniae, and Acinetobacter species. In the 28 infants with both a carriage and blood isolate, there were more (4 of 28) isolate pairs of the same species and susceptibility profile than expected by chance (p < 0.05), but most pairs were discordant (24 of 28). Logistic regression models found no association between BSI and carriage with either 3GC-RO or only 3GC-R K. pneumoniae. These analyses suggest that carriage of 3GC-RO is not a major driver of BSI caused by 3GC-RO in this setting. Comparison with environmental isolates showed very similar distributions of species and resistance patterns in the carriage, BSI, and the environment. These similar distributions, a high frequency of Acinetobacter spp. isolations, the lack of strong association between carriage and BSI, together with the high proportion of 3GC-RO in BSI all suggest that these neonates acquire multidrug-resistant carriage and blood isolates directly from the hospital environment.

Healthcare-Associated Infection Prevention Interventions for Neonates in Resource-Limited Settings

Healthcare-associated infections (HAIs) and antimicrobial-resistant (AMR) infections are leading causes of neonatal morbidity and mortality, contributing to an extended hospital stay and increased healthcare costs. Although the burden and impact of HAI/AMR in resource-limited neonatal units are substantial, there are few HAI/AMR prevention studies in these settings. We reviewed the mechanism of action and evidence supporting HAI/AMR prevention interventions, including care bundles, for hospitalized neonates in low- and middle-income countries (LMIC).

Colonization with Multidrug-Resistant Bacteria in the First Week of Life among Hospitalized Preterm Neonates in Serbia: Risk Factors and Outcomes

The aim of this prospective cohort study was to determine the prevalence of gut colonization with multidrug-resistant (MDR) bacteria, risk factors for colonization, infection risk, and outcomes among preterm neonates hospitalized at a tertiary-care center in Serbia. During the period from December 2017 to April 2018, 103 neonates were screened for rectal carriage at admission and on the seventh day of life. Characterization of MDR strains was done by conventional microbiology and molecular methods. Out of 61 (59.2%) colonized neonates, 12 (11.6%) were found colonized at admission, while 49 (47.6%) became colonized at the study site. Among a total of 72 MDR isolates, extended-spectrum beta-lactamase (ESBL)-producing enterobacteria prevailed (56/72, 77%), followed by Acinetobacter baumannii (14/72, 19%). The majority of ESBL-producing strains carried multiple genes (blaTEM/blaCTX-M-15 or blaTEM/blaSHV). Longer previous hospitalization and delivery by cesarean section were associated with MDR colonization, while mechanical ventilation was a risk factor for colonization at the study site. Infections due to MDR bacteria were more frequent among colonized than non-colonized neonates, but not significantly, and mortality was low (1%) in the studied neonates. These results indicate that hospitalized preterm neonates in Serbia are rapidly colonized with a diversity of MDR species and resistance phenotypes/genotypes.

Antimicrobial coatings for environmental surfaces in hospitals: a potential new pillar for prevention strategies in hygiene

Recent reports provide evidence that contaminated healthcare environments represent major sources for the acquisition and transmission of pathogens. Antimicrobial coatings (AMC) may permanently and autonomously reduce the contamination of such environmental surfaces complementing standard hygiene procedures. This review provides an overview of the current status of AMC and the demands to enable a rational application of AMC in health care settings. Firstly, a suitable laboratory test norm is required that adequately quantifies the efficacy of AMC. In particular, the frequently used wet testing (e.g. ISO 22196) must be replaced by testing under realistic, dry surface conditions. Secondly, field studies should be mandatory to provide evidence for antimicrobial efficacy under real-life conditions. The antimicrobial efficacy should be correlated to the rate of nosocomial transmission at least. Thirdly, the respective AMC technology should not add additional bacterial resistance development induced by the biocidal agents and co- or cross-resistance with antibiotic substances. Lastly, the biocidal substances used in AMC should be safe for humans and the environment. These measures should help to achieve a broader acceptance for AMC in healthcare settings and beyond. Technologies like the photodynamic approach already fulfil most of these AMC requirements.

Improving empiric antibiotic prescribing in pediatric bloodstream infections: a potential application of weighted-incidence syndromic combination antibiograms (WISCA)

Background: Increasing antibiotic resistance to WHO-recommended first- and second-line treatments of pediatric sepsis requires adaptation of prescribing guidelines. We discuss the potential and limitations of a weighted-incidence syndromic combination antibiogram (WISCA) as a practical tool for incorporating local microbiology data when assessing empiric coverage of commonly used antibiotics.Research design and methods: A brief questionnaire of 18 clinically significant isolates from pediatric blood cultures (Jan-Dec 2018) was sent to a global network of pediatric hospitals in July 2019. Weighted coverage estimates of non-antipseudomonal third-generation cephalosporins (3GC) and meropenem were estimated using Monte-Carlo simulation for each site reporting >100 isolates.Results: 52 hospitals in 23 countries in 5 WHO regions responded to the questionnaire; 13 sites met the sample size requirement. The most common isolates were S. aureus, Klebsiella spp., E. coli and Enterococcus spp. Coverage of 3GC ranged from 39% [95%CrI: 34-43%] to 73% (two sites: [95%CrI: 65-80%]; [95%CrI: 68-86%]) and meropenem coverage ranged from 54% [95%CrI: 47-60%] to 88% [95%CrI:84-91%].Conclusions: A WISCA is a data-driven, clinically intuitive tool that can be used to compare empiric antibiotic regimens for pediatric sepsis using existing large datasets. The estimates can be further refined using more complex meta-analytical methods and patient characteristics.

A Multicenter Clinical Study To Demonstrate the Diagnostic Accuracy of the GenMark Dx ePlex Blood Culture Identification Gram-Negative Panel

Bacteremia can progress to septic shock and death without appropriate medical intervention. Increasing evidence supports the role of molecular diagnostic panels in reducing the clinical impact of these infections through rapid identification of the infecting organism and associated antimicrobial resistance genes. We report the results of a multicenter clinical study assessing the performance of the GenMark Dx ePlex investigational-use-only blood culture identification Gram-negative panel (BCID-GN), a rapid diagnostic assay for detection of bloodstream pathogens in positive blood culture (PBC) bottles. Prospective, retrospective, and contrived samples were tested. Results from the BCID-GN were compared to standard-of-care bacterial identification methods. Antimicrobial resistance genes (ARGs) were identified using PCR and sequence analysis. The final BCID-GN analysis included 2,444 PBC samples, of which 926 were clinical samples with negative Gram stain results. Of these, 109 samples had false-negative and/or -positive results, resulting in an overall sample accuracy of 88.2% (817/926). After discordant resolution, overall sample accuracy increased to 92.9% (860/926). Pre- and postdiscordant resolution sample accuracy excludes 37 Gram-negative organisms representing 20 uncommon genera, 10 Gram-positive organisms, and 1 Candida species present in 5% of samples that are not targeted by the BCID-GN. The overall weighted positive percent agreement (PPA), which averages the individual PPAs from the 27 targets (Gram-negative and ARG), was 94.9%. The limit of detection ranged from 10⁴ to 10⁷ CFU/ml, except for one strain of Fusobacterium necrophorum at 10⁸ CFU/ml.

Impact of 1% chlorhexidine gluconate bathing and emollient application on bacterial pathogen colonization dynamics in hospitalized preterm neonates - A pilot clinical trial

BACKGROUND

Chlorhexidine gluconate (CHG) body washes and emollient application may modulate bacterial pathogen colonization and prevent neonatal hospital-acquired infections.

METHODS

This pilot, non-randomized, open-label trial, enrolled preterm neonates (1000-1500g; day 1-3 of life) at a tertiary hospital in Cape Town, South Africa. Participants were sequentially allocated to 4 trial arms (n=20 each): 1% aqueous CHG (CHG), 1% CHG plus emollient (CHG+EM), emollient only (EM) and standard of care (SOC: no antiseptic/emollient). Trial treatment/s were applied daily for 10 days (d) post-enrolment, documenting neonatal skin condition score. Anterior nose, neck, umbilical and perianal swabs for bacterial culture were collected at d1, d3, d10 and d16 post-enrolment, (±1 day), reporting pathogen acquisition rates and semi-quantitative bacterial colony counts. (ClinicalTrials.gov identifier: NCT03896893; trial status: closed).

FINDINGS

Eighty preterm neonates (mean gestational age 30 weeks [SD 2]) were enrolled between 4 March and 26 August 2019. The bacterial pathogen acquisition rate (comparing d1 and d16 swabs) varied from 33·9% [95%CI 22·9-47·0] at the umbilicus, 39·3% [95%CI 27·6-52·4] at the neck, to 71·4% [95%CI 58·5-81·7] at both the nose and perianal region. At d10, CHG babies had reduced bacterial density detected from neck, umbilicus, and perianal swabs compared to other groups (see Table 3). Following intervention cessation, colonization density was similar across all trial arms, but S. aureus colonization was more prevalent among EM and CHG+EM babies. Neonatal skin condition score improved in babies receiving emollient application (EM: -0·87 [95%CI 0·69-1·06] and CHG+EM: -0·73 [0·45-0·99]), compared to the SOC and CHG arms (Table 2); no CHG-related skin reactions occurred.

INTERPRETATION

Bacterial colonization density was significantly reduced in babies receiving 1% CHG washes but colonization levels rebounded rapidly post-intervention. Emollient application improved skin condition but was associated with higher rates of S. aureus colonization.

FUNDING

South African Medical Research Council; National Institutes of Health (TW010682).

Neonatal sepsis: within and beyond China

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Sepsis remains a significant cause of neonatal morbidity and mortality in China. A better understanding of neonatal sepsis in China as compared with other industrialized and non-industrialized countries may help optimize neonatal health care both regionally and globally. Literature cited in this review was retrieved from PubMed using the keywords “neonatal sepsis,” “early-onset (EOS)” and “late-onset (LOS)” in English, with the focus set on population-based studies. This review provides an updated summary regarding the epidemiology, pathogen profile, infectious work-up, and empirical treatment of neonatal sepsis within and beyond China. The incidence of neonatal EOS and the proportion of Group B Streptococcus (GBS) within pathogens causing EOS in China seem to differ from those in developed countries, possibly due to different population characteristics and intrapartum/postnatal health care strategies. Whether to adopt GBS screening and intrapartum antibiotic prophylaxis in China remains highly debatable. The pathogen profile of LOS in China was shown to be similar to other countries. However, viruses as potential pathogens of neonatal LOS have been underappreciated. Growing antimicrobial resistance in China reflects limitations in adapting antibiotic regimen to local microbial profile and timely cessation of treatment in non-proven bacterial infections. This review stresses that the local epidemiology of neonatal sepsis should be closely monitored in each institution. A prompt and adequate infectious work-up is critically important in diagnosing neonatal sepsis. Adequate and appropriate antibiotic strategies must be overemphasized to prevent the emergence of multi-resistant bacteria in China.

Safety and clinical application of nonbronchoscopic bronchoalveolar lavage in preterm neonates with clinical ventilator-associated pneumonia

BACKGROUND

The safety and clinical application of nonbronchoscopic bronchoalveolar lavage (NB-BAL) in preterm neonates with ventilator-associated pneumonia (VAP) have not been fully investigated, and limited data on the feasibility of this method are available.

METHODS

Premature infants with clinically suspected VAP between October 2017 and June 2019 were enrolled, and NB-BAL was performed. The tolerance and safety of NB-BAL were prospectively recorded during the procedure, and the clinical applications of NB-BAL were observed.

RESULTS

A total of 46 NB-BAL procedures were performed in 31 neonates with clinically suspected VAP. The median (interquartile range) gestational age and birth body weight were 28.7 (26.7-31.3) weeks and 1055.0 (817.0-1475.0) grams, respectively. Overall, all episodes of the procedure were well tolerated, with only 9 (19.5%) episodes showing transient desaturation and one patient (2.2%) showing bradycardia during the NB-BAL procedure. There were no impairments in arterial blood gas, cardiopulmonary parameters or respiratory severity scores after NB-BAL. No significant complications occurred in any of the patients who received NB-BAL. No chronic comorbidities affected the safety and clinical application of NB-BAL in these mechanically ventilated preterm neonates. NB-BAL yielded a diagnosis in 32 (69.6%) of these VAP episodes. Staphylococcus aureus was the most common isolated bacterium and accounted for 7 (15.2%) confirmed cases of VAP in our study, followed by polymicrobial microorganisms (n = 6, 13.0%). The appropriate antibiotics were prescribed and modified according to the NB-BAL results in 25 (54.3%) cases of VAP.

CONCLUSIONS

NB-BAL is a safe and clinically applicable method for determining the etiology and diagnosis of VAP in the NICU, even in extremely preterm neonates with major chronic comorbidities. Further studies to investigate the diagnostic accuracy and impact of NB-BAL on VAP treatment in neonates are warranted in the future.

Do isolates from pharyngeal and rectal swabs match blood culture bacterial pathogens in septic VLBW infants? A pilot, cross-sectional study

Serial body site swabbing is used to monitor horizontal spread of aggressive bacterial species in the neonatal intensive care unit (NICU). Since colonization/carriage is thought to precede systemic infection, one might expect to retrieve colonizing pathogens from blood cultures. This hypothesis, however, has not been fully investigated in very low birth weight (VLBW) infants that are at high sepsis' risk. The primary outcome was, in a population of VLBW infants with late-onset sepsis, the matching between blood culture results and pathogens isolated from rectal and nose/pharyngeal surveillance swabs in the preceding 2 weeks. The secondary outcomes were the site of swabbing and time interval from colonization to blood culture positivity. Out of 333 VLBW neonates, 80 (24%) were diagnosed with bacterial sepsis. In 46 (57%) neonates, the blood culture showed the same pathogen species cultured from a swab. Of these, 30 were isolated from infants with both body sites colonized with an average time interval of 3.5 days; 2/16 were isolated from rectal swabs and 14 /16 from nose/pharyngeal samples.Conclusion: Our data show a fair correspondence between bacteria colonizing the nasopharynx and/or the rectum and pathogens later isolated from blood cultures. This association depends on the swabbing site, number of sites, and pathogen species. Although these data constitute valuable results, they are not sufficient for providing the sole base of a thoughtful clinical decision. What is Known: • Body site's colonization may precede systemic infection. • Little is known on this mechanism in VLBW infants that are at higher sepsis' risk. What is New: •Colonizing bacteria partially correspond to pathogens of blood cultures in VLBW infants with sepsis. • Correspondence depends on swabbing site, number of sites, and pathogen species.

Antibiotische Therapie bei kritisch kranken Kindern – Ist weniger mehr?

Die antibiotische Therapie stellt eine wichtige und in vielen Fällen unverzichtbare Maßnahme zum Erreichen einer Restitutio ad integrum bei bakteriellen Infektionen dar. Hierdurch können auch schwere Infektionen bei immungeschwächten Patienten geheilt werden. Wir wissen heute aber auch, dass insbesondere kritisch kranke Kinder häufig inadäquat antibiotisch behandelt werden – mit ebenfalls potenziell schädlichen Nebenwirkungen. In diesem Spannungsfeld aus kritisch krankem Kind, der Angst, etwas zu verpassen, und potenzieller Übertherapie ist es oft nicht einfach, eine rationale Therapieentscheidung zu fällen. Im vorliegenden Review werden aktuelle Studien zu wichtigen Aspekten der antibiotischen Therapie bei kritisch kranken Kindern beleuchtet und im Hinblick auf klinische Umsetzbarkeit interpretiert. Folgende Teilaspekte werden besprochen: 1) Zeitpunkt der antibiotischen Therapie und Möglichkeiten eines abwartenden Verhaltens, 2) die Auswahl der Antibiotika in der empirischen Therapie, 3) Deeskalationsstrategien und 4) die Dauer der antibiotischen Therapie. Antibiotic-Stewardship-Programme, unter Einbeziehung von pädiatrischen Infektiologen, klinischen Pharmazeuten und Mikrobiologen, spielen bei den häufig schwierigen klinischen Entscheidungen eine entscheidende Rolle.

Rectal screening displays high negative predictive value for bloodstream infection with (ESBL-producing) Gram-negative bacteria in neonates with suspected sepsis in a low-resource setting neonatal care unit

OBJECTIVES

We analysed the concordance of rectal swab isolates and blood culture for Gram-negative bacteria (GNB) isolates in neonates with a suspicion of neonatal sepsis admitted to a neonatal care unit in Haiti.

METHODS

We matched pairs of blood and rectal samples taken on the date of suspected sepsis onset in the same neonate. We calculated the proportion of rectal isolates in concordance with the blood isolates by species and genus. We calculated the negative predictive value (NPV) for GNB and extended-spectrum β-lactamase (ESBL)-producing GNB for all rectal and blood isolate pairs in neonates with suspected sepsis.

RESULTS

We identified 238 blood and rectal samples pairs, with 238 blood isolate results and 309 rectal isolate results. The overall concordance in genus and species between blood and rectal isolates was 22.3% [95% confidence interval (CI) 17.4-28.0%] and 20.6% (95% CI 16.0-26.2%), respectively. The highest concordance between blood and rectal isolates was observed for samples with no bacterial growth (65%), followed byKlebsiella pneumoniae (18%) and Klebsiella oxytoca (12%). The NPV of detecting GNB bacterial isolates in rectal samples compared with those in blood samples was 81.6% and the NPV for ESBL-positive GNB was 92.6%.

CONCLUSIONS

The NPV of rectal swab GNB isolates was high in all patient groups and was even higher for ESBL-positive GNB. Clinicians can use the results from rectal swabs when taken simultaneously with blood samples during outbreaks to inform the (de-)escalation of antibiotic therapy in those neonates that have an ongoing sepsis profile.

Sepsis related mortality of extremely low gestational age newborns after the introduction of colonization screening for multi-drug resistant organisms

BACKGROUND

In 2013 German infection surveillance guidelines recommended weekly colonization screening for multidrug-resistant (MDRO) or highly epidemic organisms for neonatal intensive care units (NICUs) and extended hygiene measures based on screening results. It remains a matter of debate whether screening is worth the effort. We therefore aimed to evaluate sepsis related outcomes before and after the guideline update.

METHODS

The German Neonatal Network (GNN) is a prospective cohort study including data from extremely preterm infants between 22 + 0 and 28 + 6 gestational weeks born in 62 German level III NICUs.

RESULTS

Infants treated after guideline update (n = 8.903) had a lower mortality (12.5% vs. 13.8%, p = 0.036), reduced rates for clinical sepsis (31.4 vs. 42.8%, p <  0.001) and culture-proven sepsis (14.4% vs. 16.5%, p = 0.003) as compared to infants treated before update (n = 3.920). In a multivariate logistic regression analysis, nine pathogens of culture-proven sepsis were associated with sepsis-related death, e.g. Pseudomonas aeruginosa [OR 59 (19-180), p <  0.001)]. However, the guideline update had no significant effect on pathogen-specific case fatality, total sepsis-related mortality and culture-proven sepsis rates with MDRO. While the exposure of GNN infants to cefotaxime declined over time (31.1 vs. 40.1%, p <  0.001), the treatment rate with meropenem was increased (31.6 vs. 26.3%, p <  0.001).

CONCLUSIONS

The introduction of weekly screening and extended hygiene measures is associated with reduced sepsis rates, but has no effects on sepsis-related mortality and sepsis with screening-relevant pathogens. The high exposure rate to meropenem should be a target of antibiotic stewardship programs.

The Gut of Healthy Infants in the Community as a Reservoir of ESBL and Carbapenemase-Producing Bacteria

The recent rapid rise of multi-drug resistant Enterobacteriaceae (MDR-E) is threatening the treatment of common infectious diseases. Infections with such strains lead to increased mortality and morbidity. Using a cross-sectional study, we aimed to estimate the prevalence of gut colonization with extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae among healthy infants born in Pakistan, a setting with high incidence of MDR-E infections. Stool samples were collected from 104 healthy infants between the ages of 5 and 7 months. Enterobacteriaceae isolates were screened for resistance against several antimicrobial classes. Presence of ESBL and carbapenemase genes was determined using multiplex PCR. Sequence types were assigned to individual strains by multi-locus sequence typing. Phylogenetic analysis of Escherichia coli was done using the triplex PCR method. Forty-three percent of the infants were positive for ESBL-producing Enterobacteriaceae, the majority of which were E. coli. We identified several different ESBL E. coli sequence types most of which belonged to the phylogenetic group B2 (23%) or D (73%). The widespread colonization of infants in a developing country with ESBL-producing Enterobacteriaceae is concerning. The multiple sequence types and reported non-human sources support that multiple non-epidemic MDR lineages are circulating in Pakistan with healthy infants as a common reservoir.

Risk Factors of Initial Inappropriate Antibiotic Therapy and the Impacts on Outcomes of Neonates with Gram-Negative Bacteremia

BACKGROUND

Timely appropriate empirical antibiotic plays an important role in critically ill patients with gram-negative bacteremia. However, the relevant data and significant impacts have not been well studied in the neonatal intensive care unit (NICU).

METHODS

An 8-year (1 January 2007-31 December 2014) cohort study of all NICU patients with gram-negative bacteremia (GNB) in a tertiary-care medical center was performed. Inadequate empirical antibiotic therapy was defined when a patient did not receive any antimicrobial agent to which the causative microorganisms were susceptible within 24 h of blood culture sampling. Neonates with GNB treated with inadequate antibiotics were compared with those who received initial adequate antibiotics.

RESULTS

Among 376 episodes of Gram-negative bacteremia, 75 (19.9%) received inadequate empirical antibiotic therapy. The cause of inadequate treatment was mostly due to the pathogen resistance to prescribed antibiotics (88.0%). Bacteremia caused by Pseudomonas aeruginosa (Odds ratio [OR]: 20.8, P < 0.001) and extended spectrum β-lactamase (ESBL)-producing bacteria (OR: 18.4, P < 0.001) had the highest risk of inadequate treatment. Previous exposure with third generation cephalosporin was identified as the only independent risk factor (OR: 2.52, 95% CI: 1.18-5.37, P = 0.018). Empirically inadequately treated bacteremias were significantly more likely to have worse outcomes than those with adequate therapy, including a higher risk of major organ damage (20.0% versus 6.6%, P < 0.001) and infectious complications (25.3% versus 9.3%, P < 0.001), and overall mortality (22.7% versus 11.0%, P = 0.013). Conclusions: Inadequate empirical antibiotic therapy occurs in one-fifth of Gram-negative bacteremias in the NICU, and is associated with worse outcomes. Additional prospective studies are needed to elucidate the optimal timing and aggressive antibiotic regimen for neonates who are at risk of antibiotic-resistant Gram-negative bacteremia.

High Carriage Rates of Multidrug-Resistant Gram-Negative Bacteria in Neonatal Intensive Care Units From Ghana

Background

Carriage of multidrug resistant (MDR) Gram-negative bacteria (GN) in hospitalized neonates may increase the risk of difficult-to-treat invasive infections at neonatal intensive care units (NICUs). Data on MDRGN carriage among hospitalized newborns in Africa are limited.

Methods

We conducted a cross-sectional study at the NICUs of 2 tertiary hospitals in Ghana. Swabs from the axilla, groin, perianal region, and the environment were cultured, GN were identified, and antibiotic susceptibility was tested. We obtained blood culture isolates from neonates with sepsis. Whole-genome sequencing was used to characterize carbapenemase-producing Klebsiella pneumoniae. Typing was done by multilocus sequence typing (MLST) and single nucleotide polymorphism (SNP) analysis.

Results

A total of 276 GN were isolated from 228 screened neonates. Pathogenic GN were cultured in 76.8% (175 of 228) of neonates. Klebsiella spp (41.7%; 115 of 276) and Escherichia coli (26.4%; 73 of 276) were the commonest organisms. Carriage rates of MDRGN and third-generation cephalosporin resistant organisms were 49.6% (113 of 228) and 46.1% (105 of 228), respectively. Among Klebsiella spp, 75.6% (87 of 115) phenotypically expressed extended-spectrum β-lactamase activity, whereas 15.6% expressed carbapenemase and harbored bla-_OXA-181 and bla-_CTX-M-15. Overall, 7.0% (16 of 228) of neonates developed GN bloodstream infection. In 2 of 11 neonates, sequencing showed the same identity between carriage and the bloodstream isolate. Length of stay before specimen collection and antibiotic use were independently associated with carriage rates, which increased from 13% at admission to 42% by day 2 and reached a plateau at 91% by day 15.

Conclusions

High carriage rates of MDRGN, including carbapenemase-producing enterobacterales may be an emerging problem in NICUs in Africa.

Colonization Screening Targeting Multidrug-Resistant Gram-Negative Pathogens Does Not Increase the Use of Carbapenems in Very Low Birth Weight Infants

Since 2012, a colonization screening (CoS) for multidrug-resistant Gram-negative bacteria (MRGN) in very low birth weight infants (VLWBI) was implemented in order to provide a basis for an effective empiric therapy of subsequent nosocomial infections (NI). According to antibiotic stewardship, carbapenems should be reserved for NI caused by MRGN or severe NI. We examined whether the CoS increased the first-line use of carbapenems. In this retrospective cohort analysis, we enrolled all VLBWI before (2009-2011) and after (2012-2014) the introduction of CoS (2012) at a tertiary university neonatal intensive care and neonatal intermediate care unit (NIMC) in Germany. Rectal swabs were used to detect MRGN colonization (on admission and weekly until discharge from the NIMC). The use of carbapenems was measured by days of therapy (DoT). To exclude the replacement of carbapenems by other antibiotics, antibiotic therapy for late-onset sepsis (LOS) was assessed by DoT and length of therapy (LoT). In 55/201 (27.4%) VLBWI, CoS detected MRGN colonization. Compared to the cohort prior to the introduction of CoS (n = 191), a significant decrease in LoT (p < 0.001) and total DoT (p < 0.001) was seen (n = 201). This was due to a significant decrease in LoT (p < 0.001) and total DoT (p < 0.001) in the birth weight category of 1,000-1,499 g. In these infants, DoT for carbapenems (p = 0.009) was significantly lower, possibly caused by a significant decline of LOS (25 episodes vs. 39 episodes, p = 0.025). Conversely, no significant differences in LoT and total DoT were seen in infants with a birth weight <500 g (p = 1.000; p = 0.758) and in infants weighing 500-999 g (p = 0.754; p = 0.794). DoT for carbapenems was not significantly different in the total cohort after the introduction of CoS (p = 0.341). Prolonged exposure to carbapenems (in terms of DoT) significantly postponed the first detection of MRGN colonization (p = 0.023). The introduction of CoS did not result in an increased use of carbapenems. Concomitant carbapenem treatment may reduce the sensitivity of CoS relying on rectal swabs.

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.

Future Challenges in Pediatric and Neonatal Sepsis: Emerging Pathogens and Antimicrobial Resistance

The incidence of severe infections caused by multidrug-resistant (MDR) pathogens is currently rising worldwide, and increasing numbers of neonates and children with serious bloodstream infections due to resistant bacteria are being reported. Severe sepsis and septic shock due to gram-negative bacteria represent a significant cause of morbidity and mortality, and contribute to high health care costs. Antimicrobial resistance among Enterobacteriaceae represents a major problem in both health care-associated and community-acquired infections, with extended-spectrum β-lactamases (ESBLs) and carbapenem-resistant Enterobacteriaceae (CRE) now presenting the main threat. These infections in adult populations have been associated with poor clinical outcomes, but very limited data have been published so far about risk factors and clinical outcome of ESBL-associated and CRE sepsis in the pediatric population. The treatment of these infections in neonates and children is particularly challenging due to the limited number of available effective antimicrobials. Evidence-based use of new and older antibiotics based on both strategic and regulatory clinical trials is paramount to improve management of these severe infections in neonates and children.