Pathogen Distribution and Antimicrobial Resistance Among Pediatric Healthcare-Associated Infections Reported to the National Healthcare Safety Network, 2011-2014

Sustainable neonatal CLABSI surveillance: consensus towards new criteria in the Netherlands

BACKGROUND

Central line-associated bloodstream infections (CLABSI) are a main focus of infection prevention and control initiatives in neonatal care. Standardised surveillance of neonatal CLABSI enables intra- and interfacility comparisons which can contribute to quality improvement. To date, there is no national registration system for CLABSI in neonatal care in the Netherlands and several criteria are used for local monitoring of CLABSI incidence rates. To achieve standardised CLABSI surveillance we conducted a consensus procedure with regard to nationwide neonatal CLABSI surveillance criteria (SC).

METHODS

A modified Delphi consensus procedure for the development of nationwide neonatal CLABSI SC was performed between January 2016 and January 2017 in the Netherlands. An expert panel was formed by members of the Working Group on Neonatal Infectious Diseases of the Section of Neonatology of the Dutch Paediatric Society. The consensus procedure consisted of three expert panel rounds.

RESULTS

The expert panel achieved consensus on Dutch neonatal CLABSI SC. Neonatal CLABSI is defined as a bloodstream infection occurring more than 72 h after birth, associated with an indwelling central venous or arterial line and laboratory confirmed by one or more blood cultures. In addition, the blood culture finding should not be related to an infection at another site and one of the following criteria can be applied: 1. a bacterial or fungal pathogen is identified from one or more blood cultures; 2. the patient has clinical symptoms of sepsis and 2A) a common commensal is identified in two separate blood cultures or 2B) a common commensal is identified by one blood culture and C-reactive protein level is above 10 mg/L in the first 36 h following blood culture collection.

CONCLUSIONS

The newly developed Dutch neonatal CLABSI SC are concise, specified to the neonatal population and comply with a single blood culture policy in actual neonatal clinical practice. International agreement upon neonatal CLABSI SC is needed to identify best practices for infection prevention and control.

Efficacy of a coordinated strategy for containment of multidrug-resistant Gram-negative bacteria carriage in a Neonatal Intensive Care Unit in the context of an active surveillance program

Background

Antimicrobial resistance in neonatal intensive care unit (NICU) patients is a threat, due to the frequent use of antimicrobial treatment and invasive devices in fragile babies. Since 2014 an active surveillance program of multidrug-resistant Gram-negative bacteria (MDR-GNB) carriage has been in place in the five NICUs of Palermo, Italy. In 2017 an increase in the prevalence of MDR-GNB, and in particular of extended-spectrum β-lactamases-producing Klebsiella pneumoniae (ESBL-KP), was observed in “Civico” hospital NICU.

Aim

To assess the impact of a coordinated intervention strategy in achieving long-lasting reduction of MDR-GNB prevalence in the NICU.

Methods

Rectal swabs were obtained monthly and processed to detect MDR-GNB using standard methods. MDR-GNB were characterized by pulsed-field gel electrophoresis (PFGE). Since November 2017 the following intervention measures were applied: (a) two-months intensification of sample collection; (b) stakeholders meetings; (c) improvement of prevention measures and antimicrobial policies.

Findings

During the intensified microbiological surveillance MDR-GNB and ESBL-KP were detected in rectal swabs (34.8%; 23.2%), nasal swabs (24.6%; 14.5%), oral swabs (14.5%; 5.4%), milk samples (32.1%; 17.9%), pacifiers swabs (30.8%; 17.9%) and from sub-intensive room surfaces. Thirteen ESBL-KP strains isolated from clinical and environmental samples showed identical PFGE patterns. The prevalence of MDR-GNB and ESBL-KP carriage significantly decreased in the year after intervention compared to the previous year (20.6% vs 62.2%; p < 0.001 and 11.1% vs 57.8%; p < 0.001). MDR-GNB were not detected at all for three months and ESBL-KP for five months. Multivariate analysis of the principal exposure variables showed that admission in the post-intervention period significantly reduced the risk of MDR-GNB carriage (adj-OR = 0.21, 95% CI = 0.076–0.629; p < 0.001).

Conclusions

MDR-GNB broadly circulate in NICU setting, they can colonize different body sites and spread through various vehicles. A coordinated strategy of multiple interventions with active cooperation between epidemiologists and clinicians in the NICU can effectively reduce their circulation and in particular the carriage of the most dangerous ESBL-KP strains.

Healthcare-associated infections among patients hospitalized for cancers of the lip, oral cavity and pharynx

Introduction

The negative consequences of healthcare-associated infections (HAI) on the burden of illness (BOI) of cancer patients are well-established. However, there is a paucity of research on HAI among cancers of the lip, oral cavity and pharynx (CLOCP), and whether HAI-related BOI differed for other common solid tumors–malignant neoplasm of the colon (MNC) and malignant neoplasm of the lung (MNL).

Methods

We utilized the United States' National Inpatient Sample database 2017 to study longitudinal inpatient hospital stay of CLOCP, MNC and MNL. Patient demographics and hospital characteristics of patients were assessed, and the impact of HAI-related BOI compared based on differences in length of hospital stays (LOS), total charges during hospitalization and mortality were compared.

Findings

In 2017, of the 54,934 patients with CLOCP, 1.2% had HAI, compared to MNC (n=64,470) with 2% HAI and MNL (n=154,685) with 1.2% HAI. In adjusted multivariable regression analysis, we determined CLOCP patients with HAI had LOS of 5.6 days longer (95% CIs, 3.0–8.2 days, P < 0.001), and hospitalization charges of $40,341 higher (95%CIs 15,715–64,967, P < 0.01) than the non-HAI CLOCP patients. Mortality was not significantly different among HAI and non-HAI CLOCP patients (odds ratio: 0.80; 95%CIs 0.35–1.87, P = 0.6). In unadjusted analysis, LOS and total charges were higher for CLOCP-HAI patients vs. MNC-HAI or MNL-HAI patients.

Conclusion

HAI in patients with CLOCP patients were associated with an increased BOI, and this is considerably higher than observed in patients with MNC or MNL patients who had HAI.

Optimizing the Use of Antibiotic Agents in the Pediatric Intensive Care Unit: A Narrative Review

Antibiotics are one of the most prescribed drug classes in the pediatric intensive care unit, yet the incidence of inappropriate antibiotic prescribing remains high in critically ill children. Optimizing the use of antibiotics in this population is imperative to guarantee adequate treatment, avoid toxicity and the occurrence of antibiotic resistance, both on a patient level and on a population level. Antibiotic stewardship encompasses all initiatives to promote responsible antibiotic usage and the PICU represents a major target environment for antibiotic stewardship programs. This narrative review provides a summary of the available knowledge on the optimal selection, duration, dosage, and route of administration of antibiotic treatment in critically ill children. Overall, more scientific evidence on how to optimize antibiotic treatment is warranted in this population. We also give our personal expert opinion on research priorities.

Decolonization of Staphylococcus aureus

Staphylococcus aureus infections are associated with increased morbidity, mortality, hospital stay, and health care costs. S aureus colonization has been shown to increase risk for invasive and noninvasive infections. Decolonization of S aureus has been evaluated in multiple patient settings as a possible strategy to decrease the risk of S aureus transmission and infection. In this article, we review the recent literature on S aureus decolonization in surgical patients, patients with recurrent skin and soft tissue infections, critically ill patients, hospitalized non-critically ill patients, dialysis patients, and nursing home residents to inform clinical practice.

Expanding antimicrobial stewardship strategies for the NICU: Management of surgical site infections, perioperative prophylaxis, and culture negative sepsis

OBJECTIVE

To review antibiotic stewardship strategies for neonatal intensive care units (NICU) in the areas of management of surgical site infections, perioperative prophylaxis and culture negative late onset sepsis.

FINDING

Review of local microbiology, stratification of surgical procedures by risk of contamination of the surgical site, and adherence to evidence-based principles of perioperative antibiotic administration (targeted therapy, effective dosing, appropriate timing and limiting duration post-operatively) can help to minimize unnecessary antibiotic use for neonatal surgery. Creating a late onset sepsis case definition, appropriate collection and interpretation of blood cultures, and instituting antibiotic time-outs can minimize the overuse of antibiotics for culture negative sepsis.

CONCLUSION

Effective implementation of these antimicrobial stewardship strategies in the NICU can reduce unnecessary antimicrobial use and limit the emergence of resistant pathogens.

Health Care-Associated Infections Among Critically Ill Children in the US, 2013-2018

IMPORTANCE

Central catheter-associated bloodstream infections (CLABSIs) and catheter-associated urinary tract infections (CAUTIs) increase morbidity, mortality, and health care costs in pediatric patients.

OBJECTIVE

To examine changes over time in CLABSI and CAUTI rates between 2013 and 2018 in neonatal intensive care units (NICUs) and pediatric intensive care units (PICUs) using prospective surveillance data from community hospitals, children's hospitals, and pediatric units within general hospitals.

DESIGN, SETTING, AND PARTICIPANTS

This time series study included 176 US hospitals reporting pediatric health care-associated infection surveillance data to the National Healthcare Safety Network from January 1, 2013, to June 30, 2018. Patients aged 18 years or younger admitted to PICUs or level III NICUs were included in the analysis.

MAIN OUTCOMES AND MEASURES

The primary outcomes were device-associated rates of CLABSI in NICUs and PICUs and CAUTI in PICUs (infections per 1000 device-days). Secondary outcomes included population-based rates (infections per 10 000 patient-days) and device utilization (device-days per patient-days). Regression models were fit using generalized estimating equations to assess yearly changes in CLABSI and CAUTI rates, adjusted for birth weight (≤1500 vs >1500 g) in neonatal models.

RESULTS

Of the 176 hospitals, 132 hospitals with NICUs and 114 hospitals with PICUs contributed data. Of these, NICUs reported 6 064 172 patient-days and 1 363 700 central line-days and PICUs reported 1 999 979 patient-days, 925 956 central catheter-days, and 327 599 indwelling urinary catheter-days. In NICUs, there were no significant changes in yearly trends in device-associated (incidence rate ratio [IRR] per year, 0.99; 95% CI, 0.95-1.03) and population-based (IRR, 0.96; 95% CI, 0.92-1.00) CLABSI rates or central catheter utilization (odds ratio [OR], 0.97; 95% CI, 0.95-1.00). Results were similar in PICUs, with device-associated (IRR, 1.03; 95% CI, 0.99-1.07) and population-based (IRR, 1.03; 95% CI, 0.99-1.07) CLABSI rates and central catheter utilization (OR, 0.99; 95% CI, 0.97-1.01) remaining stable. While device-associated CAUTI rates in PICUs also remained unchanged over time (IRR, 0.97; 95% CI, 0.91-1.03), population-based CAUTI rates significantly decreased by 8% per year (IRR, 0.92; 95% CI, 0.86-0.98) and indwelling urinary catheter utilization significantly decreased by 6% per year (OR, 0.94; 95% CI, 0.91-0.96).

CONCLUSIONS AND RELEVANCE

Recent trends in CLABSI rates noted in this study among critically ill neonates and children in a large cohort of US hospitals indicate that past gains have held, without evidence of further improvements, suggesting novel approaches for CLABSI prevention are needed. Modest improvements in population-based CAUTI rates likely reflect more judicious use of urinary catheters.

Pediatric research priorities in healthcare-associated infections and antimicrobial stewardship

OBJECTIVE

To develop a pediatric research agenda focused on pediatric healthcare-associated infections and antimicrobial stewardship topics that will yield the highest impact on child health.

PARTICIPANTS

The study included 26 geographically diverse adult and pediatric infectious diseases clinicians with expertise in healthcare-associated infection prevention and/or antimicrobial stewardship (topic identification and ranking of priorities), as well as members of the Division of Healthcare Quality and Promotion at the Centers for Disease Control and Prevention (topic identification).

METHODS

Using a modified Delphi approach, expert recommendations were generated through an iterative process for identifying pediatric research priorities in healthcare associated infection prevention and antimicrobial stewardship. The multistep, 7-month process included a literature review, interactive teleconferences, web-based surveys, and 2 in-person meetings.

RESULTS

A final list of 12 high-priority research topics were generated in the 2 domains. High-priority healthcare-associated infection topics included judicious testing for Clostridioides difficile infection, chlorhexidine (CHG) bathing, measuring and preventing hospital-onset bloodstream infection rates, surgical site infection prevention, surveillance and prevention of multidrug resistant gram-negative rod infections. Antimicrobial stewardship topics included β-lactam allergy de-labeling, judicious use of perioperative antibiotics, intravenous to oral conversion of antimicrobial therapy, developing a patient-level "harm index" for antibiotic exposure, and benchmarking and or peer comparison of antibiotic use for common inpatient conditions.

CONCLUSIONS

We identified 6 healthcare-associated infection topics and 6 antimicrobial stewardship topics as potentially high-impact targets for pediatric research.

Preventing Catheter-Associated Urinary Tract Infections in the Pediatric Intensive Care Unit

BACKGROUND

Catheter-associated urinary tract infections are common health care-associated infections and have been associated with increased mortality, morbidity, length of stay, and cost. Prevention strategies are grouped into bundles focused on reducing unnecessary catheter use and promptly removing urinary catheters. Before intervention in the study institution, no urinary catheters were unnecessarily used and compliance with the catheter-associated urinary tract infection bundle was 84%.

OBJECTIVE

To increase bundle compliance by using targeted rounds specifically focused on eliminating dependent loops in drainage tubing and ensuring appropriate catheter use to reduce the incidence of catheter-associated urinary tract infections.

METHODS

A multidisciplinary team was formed to identify misperceptions, highlight best practices, and eliminate barriers to success over 1 year in a single pediatric intensive care unit. The team completed a quality improvement project of daily targeted rounding for patients with an indwelling urinary catheter. The goals were to assess appropriateness of catheterization, increase bundle compliance, and decrease catheter-associated urinary tract infection risk. Targeted rounds were conducted in addition to the medical team rounds.

RESULTS

Bundle compliance supported by targeted rounding increased from 84% to 93% and helped reduce the overall catheter-associated urinary tract infection rate from 2.7 infections per 1000 catheter-days at baseline to 0. This change was sustained for 1 year.

CONCLUSION

Targeted rounding for pediatric patients with an indwelling urinary catheter is an effective and sustainable strategy to reduce catheter-associated urinary tract infections. The ease of implementation for this intervention lends itself to generalizability to other patient populations.

The Role of Anesthetic Management in Surgical Site Infections After Pediatric Intestinal Surgery

BACKGROUND

Although surgical site infections (SSIs) remain a significant health care issue, a limited number of studies have analyzed risk factors for SSIs in children, particularly the role of intraoperative anesthetic management. Pediatric patients are less likely to have major adult risk factors for SSIs such as smoking and diabetes. Thus children may be more suitable as a cohort for examining the role of intraoperative anesthetics in SSIs.

AIM

We examined an association between SSI incidence and anesthetic management in children who underwent elective intestinal surgery in a single institution.

METHODS

We performed a retrospective study of 621 patients who underwent elective intestinal surgery under general anesthesia between January 2017 and September 2019, with primary outcome as the incidence of SSIs. We compared patients who were dichotomized in accordance with the median of the sevoflurane dose. We used propensity score (PS) pairwise matching of these patients to avoid selection biases. PS matching yielded 204 pairs of patients.

RESULTS

We found that higher doses of sevoflurane were associated with a higher incidence of SSIs (9.8% versus 3.9%, P = 0.019). We adjusted for intraoperative factors that were not included in the PS adjustment factors, and multivariate regression analysis after PS matching showed compatible results (odds ratio: 2.58, 95% confidence interval: 1.11-6.04, P = 0.028).

CONCLUSIONS

Higher doses of sevoflurane are associated with increased odds of SSIs after pediatric elective intestinal surgery. A randomized controlled study of volatile anesthetic-based versus intravenous anesthetic-based anesthesia will be needed to further determine the role of anesthetic drugs in SSI risk.

Effect of Contact Precautions on Staphylococcus aureus and Clinical Outcomes of Colonized Patients in the Neonatal Intensive Care Unit

BACKGROUND

Staphylococcus aureus is a common pathogen in neonatal intensive care units (NICUs), yet little is known about the effect of contact precautions and clinical outcomes of colonized patients.

METHODS

Retrospective cohort study of all neonates from August 2014 to November 2018 colonized with either methicillin-resistant S. aureus (MRSA) or methicillin-susceptible S. aureus (MSSA) and select noncolonized patients at two neonatal intensive care units at the University of California, Los Angeles. Outcomes during two time periods (during and after the use of contact precautions) were assessed.

RESULTS

A total of 234 patients were included in the study: 83 colonized and 151 noncolonized patients. There was a fourfold higher incidence of MSSA colonization versus MRSA (P < 0.001). There was a higher incidence of positive surveillance cultures after contact precautions were discontinued (P = 0.01), but this did not correlate with a higher incidence of invasive cultures (P = 0.475). There were twice as many MSSA invasive cultures than MRSA, but a higher rate of invasion with MRSA (P < 0.05). Colonized patients were more likely to develop an invasive infection than noncolonized (P = 0.003 MRSA; P = 0.004 MSSA). When controlling for gestational age and surgical interventions, colonization was more likely to be associated with skin and soft tissue infections (P < 0.001) and a longer length of stay by a mean of 27.8 days (P < 0.0001).

CONCLUSIONS

Contact precautions resulted in a lower incidence of colonization without a difference in invasive cultures in our NICUs. Those colonized with S. aureus had a higher incidence of skin and soft tissue infections and a longer NICU length of stay.

Management of Enteral Nutrition in the Pediatric Intensive Care Unit: Prokinetic Effects of Amoxicillin/Clavulanate in Real Life Conditions

PURPOSE

Malnutrition is a common feature in critically ill children. Enteral nutrition (EN) is the main strategy to nutritionally support critical ill children, but its use can be hindered by the development of intolerance. The study aimed to assess the effectiveness and safety of amoxicillin/clavulanate (A/C) to treat EN intolerance.

METHODS

We retrospectively evaluated patients admitted to the pediatric intensive care unit from October 2018 to October 2019. We conducted a case-control study: in the first 6 months (October 2018-April 2019) we implemented the nutritional protocol of our Institution with no drug, whereas in the second half (May 2019-October 2019) we employed A/C for 1 week at a dose of 10 mg/kg twice daily.

RESULTS

Twelve cases were compared with 12 controls. At the final evaluation, enteral intake was significantly higher than that at baseline in the cases (from 2.1±3.7 to 66.1±27.4% of requirement, p=0.0001 by Wilcoxon matched-pairs signed rank test) but not in the controls (from 0.2±0.8 to 6.0±14.1% of the requirement, p=NS). Final gastric residual volume at the end of the observation was significantly lower in the cases than in the controls (p=0.0398). The drug was well tolerated as shown by the similar safety outcomes in both cases and controls.

CONCLUSION

Malnutrition exposes critically ill children to several complications that affect the severity of disease course, length of stay, and mortality; all may be prevented by early EN. The development of intolerance to EN could be addressed with the use of A/C. Future prospective clinical trials are needed to confirm these conclusions.

Frequency and antimicrobial susceptibility of bacteria causing bloodstream infections in pediatric patients from United States (US) medical centers (2014-2018): therapeutic options for multidrug-resistant bacteria

Studies evaluating large series of pediatric patients with bloodstream infections (BSIs) are scarce. We evaluated the frequency and antimicrobial susceptibility of organisms isolated from pediatric patients with BSI and therapeutic options for BSI caused by multidrug-resistant (MDR) organisms. A total of 2423 organisms were consecutively collected from 33 US medical centers between 2014 and 2018, and susceptibility was tested by reference broth microdilution methods. Isolates with an extended-spectrum β-lactamase phenotype were screened for β-lactamase genes. Overall, 40.2% of organisms were Gram-negative bacteria, 57.0% Gram-positives, and 2.8% Candida spp. The 5 most common organisms were Staphylococcus aureus (26.0%), Escherichia coli (13.0%), coagulase-negative staphylococci (8.3%), Enterococcus faecalis (7.1%), and Klebsiella pneumoniae (6.9%). Among S. aureus, 26.0% were oxacillin-resistant and 99.8% were susceptible to ceftaroline (MIC50/90, 0.25/0.5 mg/L). Enterobacterales and Pseudomonas aeruginosa isolates combined represented >85% of Gram-negative bacteria, and all isolates (100.0%) were susceptible to ceftazidime-avibactam.

Molecular epidemiology of methicillin-susceptible Staphylococcus aureus in infants in a neonatal intensive care unit

OBJECTIVE

To investigate the molecular epidemiology of methicillin-susceptible Staphylococcus aureus (MSSA) in infants in a neonatal intensive care unit (NICU) using whole-genome sequencing.

DESIGN

Investigation of MSSA epidemiology in a NICU.

SETTING

Single-center, level IV NICU.

METHODS

Universal S. aureus screening was done using a single swab obtained from the anterior nares, axilla, and groin area of infants in the NICU on a weekly basis. Core genome multilocus sequence type (cgMLST) analysis was performed on MSSA isolates detected over 1 year (2018-2019).

RESULTS

In total, 68 MSSA-colonized infants were identified, and cgMLSTs of 67 MSSA isolates were analyzed. Overall, we identified 11 cgMLST isolate groups comprising 39 isolates (58%), with group sizes ranging from 2 to 10 isolates, and 28 isolates (42%) were unrelated to each other or any of the isolate groups. Cases of infants colonized by MSSA were scattered throughout the 1-year study period, and isolates belonging to the same cgMLST group were typically detected contemporaneously, over a few weeks or a few months. Overall, 13 infants (19.7%) developed MSSA infections: bacteremia (n = 3), wound infection (n = 5), conjunctivitis (n = 4), and cellulitis (n = 1). We detected no association between these clinically manifest infections and specific cgMLST groups.

CONCLUSIONS

Although MSSA isolates in infants in a NICU showed high diversity, most were related to other isolates, albeit within small groups. cgMLST facilitates an understanding of the complex transmission dynamics of MSSA in NICUs, and these data can be used to inform better control strategies.

Minimising Blood Stream Infection: Developing New Materials for Intravascular Catheters

Catheter related blood stream infection is an ever present hazard for those patients requiring venous access and particularly for those requiring long term medication. The implementation of more rigorous care bundles and greater adherence to aseptic techniques have yielded substantial reductions in infection rates but the latter is still far from acceptable and continues to place a heavy burden on patients and healthcare providers. While advances in engineering design and the arrival of functional materials hold considerable promise for the development of a new generation of catheters, many challenges remain. The aim of this review is to identify the issues that presently impact catheter performance and provide a critical evaluation of the design considerations that are emerging in the pursuit of these new catheter systems.

The implication of intestinal bacterial translocation in central line associated blood stream infections in the pediatric population

INTRODUCTION

Bacterial intestinal translocation plays an important role in neonatal sepsis. We aimed to elucidate the importance of such translocation in causing central line associated blood stream infection (CLABSI) in patients undergoing gastrointestinal surgery (GIS).

METHODS

Using a database of pediatric patients with CLABSI, patients were divided into those who had a GI-surgery (where intestines were opened), those who had a non-GI-surgery (NGIS; all other types of surgery) and those who had no surgery (NS). Data regarding type of organisms isolated on culture, their resistance patterns, clearance of CLABSI, type of antibiotic therapy and patient demographics were collected.

RESULTS

117 CLABSIs were identified between 2011 and 2018. 26 patients had GIS, 22 had NGIS and 69 had NS. NS patients were younger. 80% of GIS and NGIS patients had a central line at the time of surgery. Coagulase-negative staphylococcus (CoNS) was the most common organism isolated (32%). CoNS was more common in GIS compared to NGIS and NS (58% vs. 9% vs. 29% respectively, p=0.04). There were no differences in the time to resolution of bacteremia, mortality rates or need to remove the central line.

CONCLUSIONS

This information should help inform efforts for prevention of CLABSIs in patients undergoing GI surgery with central lines present.

LEVEL OF EVIDENCE

III.

Standardized Discharge Antibiotics May Reduce Readmissions in Pediatric Perforated Appendicitis

BACKGROUND

Based on limited evidence, the American Pediatric Surgical Association recommends 5-7 d of postoperative antibiotics in perforated appendicitis for preventing intra-abdominal abscess (IAA). In 2015, our institutional clinical practice guideline was modified to standardize prescription for 7 additional days of oral antibiotics after discharge. We hypothesized that prescribing oral antibiotics after discharge would be associated with fewer complications in perforated appendicitis.

MATERIALS AND METHODS

A retrospective cohort study was conducted of pediatric (younger than 18 y) patients who underwent laparoscopic appendectomy for perforated appendicitis (August 1, 2012-April 30, 2019). Patients diagnosed with IAA before discharge or with a postoperative length of stay ≥8 d were excluded. Patient outcomes were compared prestandardization and poststandardization of discharge antibiotics.

RESULTS

Of 617 patients, 212 (34.5%) were admitted prestandardization and 404 (65.5%) poststandardization. Overall, 409 patients (66.3%) received discharge antibiotics. The median total postoperative antibiotic duration was 4 d (interquartile range, 3-5) prestandardization versus 11 d (interquartile range, 10-12) poststandardization (P < 0.001). Prestandardization patients had a higher rate of IAA (8.9% versus 4.5%, P = 0.03) and were readmitted more frequently (13.1% versus 6.4%, P = 0.005). On adjusted analysis, admission poststandardization was associated with reduced odds of IAA (odds ratio, 0.51; 95% confidence interval, 0.25-1.06), but the relationship was imprecise. Admission poststandardization was significantly associated with reduced adjusted odds of readmission (odds ratio, 0.46; 95% confidence interval, 0.25-0.85).

CONCLUSIONS

Prescription for seven additional days of oral antibiotics after discharge was associated with reduced odds of readmission in pediatric perforated appendicitis. This population may benefit from a longer postoperative antibiotic course than currently recommended.

Artificial Intelligence-Based Multimodal Risk Assessment Model for Surgical Site Infection (AMRAMS): Development and Validation Study

Background

Surgical site infection (SSI) is one of the most common types of health care–associated infections. It increases mortality, prolongs hospital length of stay, and raises health care costs. Many institutions developed risk assessment models for SSI to help surgeons preoperatively identify high-risk patients and guide clinical intervention. However, most of these models had low accuracies.

Objective

We aimed to provide a solution in the form of an Artificial intelligence–based Multimodal Risk Assessment Model for Surgical site infection (AMRAMS) for inpatients undergoing operations, using routinely collected clinical data. We internally and externally validated the discriminations of the models, which combined various machine learning and natural language processing techniques, and compared them with the National Nosocomial Infections Surveillance (NNIS) risk index.

Methods

We retrieved inpatient records between January 1, 2014, and June 30, 2019, from the electronic medical record (EMR) system of Rui Jin Hospital, Luwan Branch, Shanghai, China. We used data from before July 1, 2018, as the development set for internal validation and the remaining data as the test set for external validation. We included patient demographics, preoperative lab results, and free-text preoperative notes as our features. We used word-embedding techniques to encode text information, and we trained the LASSO (least absolute shrinkage and selection operator) model, random forest model, gradient boosting decision tree (GBDT) model, convolutional neural network (CNN) model, and self-attention network model using the combined data. Surgeons manually scored the NNIS risk index values.

Results

For internal bootstrapping validation, CNN yielded the highest mean area under the receiver operating characteristic curve (AUROC) of 0.889 (95% CI 0.886-0.892), and the paired-sample t test revealed statistically significant advantages as compared with other models (P<.001). The self-attention network yielded the second-highest mean AUROC of 0.882 (95% CI 0.878-0.886), but the AUROC was only numerically higher than the AUROC of the third-best model, GBDT with text embeddings (mean AUROC 0.881, 95% CI 0.878-0.884, P=.47). The AUROCs of LASSO, random forest, and GBDT models using text embeddings were statistically higher than the AUROCs of models not using text embeddings (P<.001). For external validation, the self-attention network yielded the highest AUROC of 0.879. CNN was the second-best model (AUROC 0.878), and GBDT with text embeddings was the third-best model (AUROC 0.872). The NNIS risk index scored by surgeons had an AUROC of 0.651.

Conclusions

Our AMRAMS based on EMR data and deep learning methods—CNN and self-attention network—had significant advantages in terms of accuracy compared with other conventional machine learning methods and the NNIS risk index. Moreover, the semantic embeddings of preoperative notes improved the model performance further. Our models could replace the NNIS risk index to provide personalized guidance for the preoperative intervention of SSIs. Through this case, we offered an easy-to-implement solution for building multimodal RAMs for other similar scenarios.

Microbiology and Risk Factors for Hospital-Associated Bloodstream Infections Among Pediatric Hematopoietic Stem Cell Transplant Recipients

Background

Children undergoing hematopoietic stem cell transplantation (HSCT) are at high risk for hospital-associated bloodstream infections (HA-BSIs). This study aimed to describe the incidence, microbiology, and risk factors for HA-BSI in pediatric HSCT recipients.

Methods

We performed a single-center retrospective cohort study of children and adolescents (<18 years of age) who underwent HSCT over a 20-year period (1997–2016). We determined the incidence and case fatality rate of HA-BSI by causative organism. We used multivariable Poisson regression to identify risk factors for HA-BSI.

Results

Of 1294 patients, the majority (86%) received an allogeneic HSCT, most commonly with umbilical cord blood (63%). During the initial HSCT hospitalization, 334 HA-BSIs occurred among 261 (20%) patients. These were classified as gram-positive bacterial (46%), gram-negative bacterial (24%), fungal (12%), mycobacterial (<1%), or polymicrobial (19%). During the study period, there was a decline in the cumulative incidence of HA-BSI (P = .021) and, specifically, fungal HA-BSIs (P = .002). In multivariable analyses, older age (incidence rate ratio [IRR], 1.03; 95% confidence interval [CI], 1.01–1.06), umbilical cord blood donor source (vs bone marrow; IRR, 1.69; 95% CI, 1.19–2.40), and nonmyeloablative conditioning (vs myeloablative; IRR, 1.85; 95% CI, 1.21–2.82) were associated with a higher risk of HA-BSIs. The case fatality rate was higher for fungal HA-BSI than other HA-BSI categories (21% vs 6%; P = .002).

Conclusions

Over the past 2 decades, the incidence of HA-BSIs has declined among pediatric HSCT recipients at our institution. Older age, umbilical cord blood donor source, and nonmyeloablative conditioning regimens are independent risk factors for HA-BSI among children undergoing HSCT.

Salmonella Typhimurium biofilm disruption by a human antibody that binds a pan-amyloid epitope on curli

Bacterial biofilms, especially those associated with implanted medical devices, are difficult to eradicate. Curli amyloid fibers are important components of the biofilms formed by the Enterobacteriaceae family. Here, we show that a human monoclonal antibody with pan-amyloid-binding activity (mAb 3H3) can disrupt biofilms formed by Salmonella enterica serovar Typhimurium in vitro and in vivo. The antibody disrupts the biofilm structure, enhancing biofilm eradication by antibiotics and immune cells. In mice, 3H3 injections allow antibiotic-mediated clearance of catheter-associated S. Typhimurium biofilms. Thus, monoclonal antibodies that bind a pan-amyloid epitope have potential to prevent or eradicate bacterial biofilms.

Curli amyloid fibers are important components of bacterial biofilms formed by E. coli and Salmonella. Here, Tursi et al. show that a human monoclonal antibody with pan-amyloid binding activity can disrupt biofilms formed by Salmonella Typhimurium in vitro and in vivo.

Carbapenem-Resistant Gram-Negative Bacterial Infections in Children

Carbapenem-resistant organisms (CRO) are a major global public health threat. Enterobacterales hydrolyze almost all β-lactams through carbapenemase production. Infections caused by CRO are challenging to treat due to the limited number of antimicrobial options. This leads to significant morbidity and mortality. Over the last few years, several new antibiotics effective against CRO have been approved. Some of them (e.g., plazomicin or imipenem-cilastatin-relebactam) are currently approved for use only by adults; others (e.g., ceftazidime-avibactam) have recently been approved for use by children. Recommendations for antibiotic therapy of CRO infections in pediatric patients are based on evidence mainly from adult studies. The availability of pediatric pharmacokinetic and safety data is the cornerstone to broaden the use of proposed agents in adults to the pediatric population. This article provides a comprehensive review of the current knowledge regarding infections caused by CRO with a focus on children, which includes epidemiology, risk factors, outcomes, and antimicrobial therapy management, with particular attention being given to new antibiotics.

Pediatric Blood Cultures and Antibiotic Resistance: An Overview

Bloodstream infections (BSI) due to multidrug-resistant organisms, especially from pediatric intensive care units (PICU), are being increasingly reported across the world. Since BSI is associated with high mortality, it is essential to treat these infections early with appropriate antibiotics. Surveillance of etiology and emerging antimicrobial resistance (AMR) is considered an important step in the formulation of antibiotic policy for early treatment and judicious use of antibiotics. In this review on etiology and its antibiogram in community acquired BSI, S. typhi followed by S. paratyphi A were the major bacterial isolates. Quinolone resistance of more than 90% in Salmonella is now reported from all over India. Ceftriaxone remains the drug of choice for enteric fever due to its 100% susceptibility. In PICU there is an emergence of candidemia due to non-albicans candida which are now predominant isolates at few centers. BSI due to gram-negative bacteria, mostly by Klebseilla pneumoniae and gram-positive cocci (S. aureus) are the other major pathogens commonly observed in BSI from PICU. There is a high prevalence of antimicrobial resistance to commonly used antibiotics like ampicillin (94.9%-90.7%), cefotaxime (92.4%-71.4%), piperacillin-tazobactum (31.2%-27.5%) and levofloxacin (42.4%-39.8%). Resistance to carbapenems, primarily due to bla_NDM is seen in all the centers and the rate varies between 1%- 79% with K. pneumoniae and A. baumannii showing the maximum resistance. This review highlights the magnitude of the AMR in the pediatric population and calls for the urgent implementation of antimicrobial stewardship programs to save the remaining antimicrobials.

Effect of Treating Parents Colonized With Staphylococcus aureus on Transmission to Neonates in the Intensive Care Unit: A Randomized Clinical Trial

IMPORTANCE

Staphylococcus aureus is a leading cause of health care-associated infections in the neonatal intensive care unit (NICU). Parents may expose neonates to S aureus colonization, a well-established predisposing factor to invasive S aureus disease.

OBJECTIVE

To test whether treating parents with intranasal mupirocin and topical chlorhexidine compared with placebo would reduce transmission of S aureus from parents to neonates.

DESIGN, SETTING, AND PARTICIPANTS

Double-blinded randomized clinical trial in 2 tertiary NICUs in Baltimore, Maryland. Neonates (n = 236) with S aureus-colonized parent(s) were enrolled. The study period was November 7, 2014, through December 13, 2018.

INTERVENTIONS

Parents were assigned to intranasal mupirocin and 2% chlorhexidine-impregnated cloths (active treatment, n = 117) or petrolatum intranasal ointment and nonmedicated soap cloths (placebo, n = 119) for 5 days.

MAIN OUTCOMES AND MEASURES

The primary end point was concordant S aureus colonization by 90 days, defined as neonatal acquisition of an S aureus strain that was the same strain as a parental strain at time of screening. Secondary outcomes included neonatal acquisition of any S aureus strain and neonatal S aureus infections.

RESULTS

Among 236 randomized neonates, 208 were included in the analytic sample (55% male; 76% singleton births; mean birth weight, 1985 g [SD, 958 g]; 76% vaginal birth; mean parent age, 31 [SD, 7] years), of whom 18 were lost to follow-up. Among 190 neonates included in the analysis, 74 (38.9%) acquired S aureus colonization by 90 days, of which 42 (56.8%) had a strain concordant with a parental baseline strain. In the intervention and placebo groups, 13 of 89 neonates (14.6%) and 29 of 101 neonates (28.7%), respectively, acquired concordant S aureus colonization (risk difference, -14.1% [95% CI, -30.8% to -3.9%]; hazard ratio [HR], 0.43 [95.2% CI, 0.16 to 0.79]). A total of 28 of 89 neonates (31.4%) in the intervention group and 46 of 101 (45.5%) in the control group acquired any S aureus strain (HR, 0.57 [95% CI, 0.31 to 0.88]), and 1 neonate (1.1%) in the intervention group and 1 neonate (1.0%) in the control group developed an S aureus infection before colonization. Skin reactions in parents were common (4.8% intervention, 6.2% placebo).

CONCLUSIONS AND RELEVANCE

In this preliminary trial of parents colonized with S aureus, treatment with intranasal mupirocin and chlorhexidine-impregnated cloths compared with placebo significantly reduced neonatal colonization with an S aureus strain concordant with a parental baseline strain. However, further research is needed to replicate these findings and to assess their generalizability.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02223520.

Antibiotic Susceptibility and Therapy in Central Line Infections in Pediatric Home Parenteral Nutrition Patients

BACKGROUND

Patients receiving home parenteral nutrition (HPN) are at high-risk for central line-associated bloodstream infections (CLABSI). There are no published management guidelines, however, for the antibiotic treatment of suspected CLABSI in this population. Historical microbiology data may help inform empiric antimicrobial regimens in this population.

OBJECTIVE

The aim of the study was to describe antimicrobial resistance patterns and determine the most appropriate empiric antibiotic therapy in HPN-dependent children experiencing a community-acquired CLABSI.

METHODS

Single-center retrospective cohort study evaluating potential coverage of empiric antibiotic regimens in children on HPN who developed a community-acquired CLABSI.

RESULTS

From October 1, 2011 to September 30, 2017, there were 309 CLABSI episodes among 90 HPN-dependent children with median age 3.8 years old.Fifty-nine percent of patients carried the diagnosis of surgical short bowel syndrome. Organisms isolated during these infections included 60% Gram-positive bacteria, 34% Gram-negative bacteria, and 6% fungi. Among all staphylococcal isolates, 51% were methicillin sensitive. Among enteric Gram-negative organisms, sensitivities were piperacillin-tazobactam 71%, cefepime 97%, and meropenem 99%. Organisms were sensitive to current institutional standard therapy with vancomycin and piperacillin-tazobactam in 69% of cases compared with vancomycin and cefepime or vancomycin an meropenem in 85% and 96% of cases (both P < 0.01).

CONCLUSIONS

Empiric antimicrobial therapy for suspected CLABSI in HPN-dependent children should include therapy for methicillin-resistant staphylococci as well as enteric Gram-negative organisms. Future studies are needed to evaluate clinical outcomes based upon evidence-based antimicrobial regimens.

Clinical, Epidemiologic, and Laboratory Aspects of Methicillin-Resistant Staphylococcus aureus Infections

Oxacillin-resistant Staphylococcus aureus (abbreviated MRSA for historical reasons) is a major pathogen responsible for both hospital- and community-onset disease. Resistance to oxacillin in most clinical isolates of S. aureus is mediated by PBP2a, a penicillin-binding protein with low affinity to beta-lactams, encoded primarily by the mecA gene. Rapid and accurate methods of susceptibility testing of S. aureus isolates to identify MRSA infections are important tools to limit the spread of this organism. This review focuses on the clinical significance of MRSA infections and new approaches for the laboratory diagnosis and epidemiologic typing of MRSA strains.

Introduction of NGS in Environmental Surveillance for Healthcare-Associated Infection Control

The hospital environment significantly contributes to the onset of healthcare associated infections (HAIs), representing the most frequent and severe complications related to health care. The monitoring of hospital surfaces is generally addressed by microbial cultural isolation, with some performance limitations. Hence there is need to implement environmental surveillance systems using more effective methods. This study aimed to evaluate next-generation sequencing (NGS) technologies for hospital environment microbiome characterization, in comparison with conventional and molecular methods, in an Italian pediatric hospital. Environmental samples included critical surfaces of randomized rooms, surgical rooms, intensive care units and delivery rooms. The resistome of the contaminating population was also evaluated. NGS, compared to other methods, detected with higher sensitivity the environmental bacteria, and was the only method able to detect even unsearched bacteria. By contrast, however, it did not detect mycetes, nor it could distinguish viable from dead bacteria. Microbiological and PCR methods could identify and quantify mycetes, in addition to bacteria, and PCR could define the population resistome. These data suggest that NGS could be an effective method for hospital environment monitoring, especially if flanked by PCR for species identification and resistome characterization, providing a potential tool for the control of HAI transmission.

A 1-year survey of catheter-related infections in a pediatric university hospital: A prospective study

BACKGROUND

Central venous catheters (CVCs) provide a great comfort for hospitalized children. However, CVCs increase the risk of severe infection. As there are few data regarding pediatric epidemiology of catheter-related infections (CRIs), the main objective of this study was to measure the incidence rate of CRIs in our pediatric university hospital. We also sought to characterize the CRIs and to identify risk factors.

MATERIALS AND METHODS

We conducted an epidemiological prospective monocentric study including all CVCs, except Port-a-Caths and arterial catheters, inserted in children from birth to 18 years of age between April 2015 and March 2016 in the pediatric University Hospital of Nantes. Our main focus was the incidence rate of CRIs, defined according to French guidelines, while distinguishing between bloodstream infections (CRBIs) and non-bloodstream infections (CRIWBs). The incidence rate was also described for each pediatric ward. We analyzed the association between infection and potential risk factors using univariate and multivariate analysis by Cox regression.

RESULTS

We included 793 CVCs with 60 CRBIs and four CRIWBs. The incidence rate was 4.6/1000 catheter-days, with the highest incidence rate occurring in the neonatal intensive care unit (13.7/1000 catheter-days). Coagulase-negative staphylococci were responsible for 77.5% of the CRIs. Factors independently associated with a higher risk of infection in neonates were invasive ventilation and low gestational age.

CONCLUSIONS

The incidence of CRIs in children hospitalized in our institution appears to be higher than the typical rate of CRIs reported in the literature. This was particularly true for neonates. These results should lead us to reinforce preventive measures and antibiotic stewardship but they also raise the difficulty of diagnosing with certainty CRIs in neonates.

Antimicrobial-resistant pathogens associated with adult healthcare-associated infections: Summary of data reported to the National Healthcare Safety Network, 2015-2017

OBJECTIVE

Describe common pathogens and antimicrobial resistance patterns for healthcare-associated infections (HAIs) that occurred during 2015-2017 and were reported to the Centers for Disease Control and Prevention's (CDC's) National Healthcare Safety Network (NHSN).

METHODS

Data from central line-associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), ventilator-associated events (VAEs), and surgical site infections (SSIs) were reported from acute-care hospitals, long-term acute-care hospitals, and inpatient rehabilitation facilities. This analysis included device-associated HAIs reported from adult location types, and SSIs among patients ≥18 years old. Percentages of pathogens with nonsusceptibility (%NS) to selected antimicrobials were calculated for each HAI type, location type, surgical category, and surgical wound closure technique.

RESULTS

Overall, 5,626 facilities performed adult HAI surveillance during this period, most of which were general acute-care hospitals with <200 beds. Escherichia coli (18%), Staphylococcus aureus (12%), and Klebsiella spp (9%) were the 3 most frequently reported pathogens. Pathogens varied by HAI and location type, with oncology units having a distinct pathogen distribution compared to other settings. The %NS for most pathogens was significantly higher among device-associated HAIs than SSIs. In addition, pathogens from long-term acute-care hospitals had a significantly higher %NS than those from general hospital wards.

CONCLUSIONS

This report provides an updated national summary of pathogen distributions and antimicrobial resistance among select HAIs and pathogens, stratified by several factors. These data underscore the importance of tracking antimicrobial resistance, particularly in vulnerable populations such as long-term acute-care hospitals and intensive care units.

Antimicrobial-resistant pathogens associated with pediatric healthcare-associated infections: Summary of data reported to the National Healthcare Safety Network, 2015-2017

OBJECTIVE

To describe common pathogens and antimicrobial resistance patterns for healthcare-associated infections (HAIs) among pediatric patients that occurred in 2015-2017 and were reported to the Centers for Disease Control and Prevention's National Healthcare Safety Network (NHSN).

METHODS

Antimicrobial resistance data were analyzed for pathogens implicated in central line-associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), ventilator-associated pneumonias (VAPs), and surgical site infections (SSIs). This analysis was restricted to device-associated HAIs reported from pediatric patient care locations and SSIs among patients <18 years old. Percentages of pathogens with nonsusceptibility (%NS) to selected antimicrobials were calculated by HAI type, location type, and surgical category.

RESULTS

Overall, 2,545 facilities performed surveillance of pediatric HAIs in the NHSN during this period. Staphylococcus aureus (15%), Escherichia coli (12%), and coagulase-negative staphylococci (12%) were the 3 most commonly reported pathogens associated with pediatric HAIs. Pathogens and the %NS varied by HAI type, location type, and/or surgical category. Among CLABSIs, the %NS was generally lowest in neonatal intensive care units and highest in pediatric oncology units. Staphylococcus spp were particularly common among orthopedic, neurosurgical, and cardiac SSIs; however, E. coli was more common in abdominal SSIs. Overall, antimicrobial nonsusceptibility was less prevalent in pediatric HAIs than in adult HAIs.

CONCLUSION

This report provides an updated national summary of pathogen distributions and antimicrobial resistance patterns among pediatric HAIs. These data highlight the need for continued antimicrobial resistance tracking among pediatric patients and should encourage the pediatric healthcare community to use such data when establishing policies for infection prevention and antimicrobial stewardship.

Direct molecular detection of amoxicillin-susceptible E. coli in urine samples from children with suspected urinary tract infection: A potential tool to improve antibiotic stewardship and patient care

BACKGROUND

Rapid detection of amoxicillin-susceptible Escherichia coli (ASEC) urinary tract infections (UTIs) could have a significant impact on patient care and improve antibiotic stewardship. This is especially true for infants and children, for whom antibiotic choices are more limited than for adults.

METHODS

A real-time polymerase chain reaction (PCR) uniplex panel for detection of ASEC using PCR assays for E. coli and five resistance genes (bla _TEM, bla _SHV, bla _OXA, bla _CTX-M, and bla _CMY) and an internal control was designed. PCR was then performed directly on pediatric urine samples using an inhibitor-resistant DNA polymerase. The main outcome measure was the performance of the PCR panel (sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV], accuracy) for the detection of ASEC. ASEC samples were defined as those that were E. coli PCR positive and PCR negative for all five resistance genes. PCR results were compared with the reference standard for culture and susceptibility testing.

RESULTS

Two hundred and six urine samples with pyuria (>10 white blood cells/high power field) were tested with the PCR panel. Two samples showed PCR inhibition (1%). For ASEC detection, the PCR panel showed a sensitivity of 91.53% (95% CI 81.32% to 97.19%), specificity of 98.21% (95% CI 90.45% to 99.95%), PPV of 98.18% (95% CI 88.54% to 99.74%), NPV of 91.67% (95% CI 82.61% to 96.22%), and accuracy of 94.78% (95% CI 88.99% to 98.06%).

CONCLUSIONS

This PCR method could potentially enable amoxicillin or ampicillin to be used in a greater proportion of children with E. coli UTIs, improving antibiotic stewardship.

Fecal Microbiome Characteristics and the Resistome Associated With Acquisition of Multidrug-Resistant Organisms Among Elderly Subjects

Infections caused by multidrug-resistant organisms (MDRO) lead to considerable morbidity and mortality. The elderly population residing in nursing homes are a major reservoir of MDRO. Our objective was to characterize the fecal microbiome of 82 elderly subjects from 23 nursing homes and compare their resistome to that of healthy young persons. Comparisons of microbiome composition and the resistome between subjects who acquired MDRO or not were analyzed to characterize specific microbiome disruption indices (MDI) associated with MDRO acquisition. An approach based on both 16S rRNA amplicon and whole metagenome shotgun (WMS) sequencing data was used. The microbiome of the study cohort was substantially perturbed, with Bacteroides, Firmicutes, and Proteobacteria predominating. Compared to healthy persons, the cohort of elderly persons had an increased number, abundance, and diversity of antimicrobial resistance genes. High proportions of study subjects harbored genes for multidrug-efflux pumps (96%) and linezolid resistance (52%). Among the 302 antimicrobial resistance gene families identified in any subject, 60% were exclusively detected within the study cohort, including Class D beta-lactamase genes. Subjects who acquired MDRO or not had significant differences in bacterial taxa; Odoribacter laneus, and Akkermansia muciniphila were significantly greater among subjects who did not acquire MDRO whereas Blautia hydrogenotrophica predominated among subjects who acquired MDRO. These findings suggest that specific MDI may identify persons at high risk of acquiring MDRO.

Surveillance of multidrug-resistant bacteria in pediatric and neonatal intensive care units in Rio de Janeiro State, Brazil

INTRODUCTION

Multi-drug-resistant bacteria surveillance (MDR) systems are used to identify the epidemiology of MDR bacteria in neonates and children. This study aimed to describe the patterns by which MDR bacteria colonize and infect neonatal (NICU) and pediatric intensive care unit (PICU) patients in the state of Rio de Janeiro State, Brazil.

METHODS

A cross-sectional survey was performed using electronic data on NICU and PICU patients reported to the Rio de Janeiro State MDR bacteria surveillance system. All healthcare institutions that reported at least one case during the study period were included.

RESULTS

Between 2014 and 2017, 10,210 MDR bacteria cases, including 9261 colonizations and 949 infections, were reported. Among the colonizations, 5379 occurred in NICUs and 3882 in PICUs, while 405 infections occurred in NICUs and 544 in PICUs. ESBL producing Klebsiella sp and E. coli were the most reported colonization-causing agents in NICUs (1983/5379, 36.9%) and PICUs (1494/3882; 38.5%). The main causing bacteria reported in catheter-associated bloodstream infection (CLABSI), ventilator associated pneumonia, and catheter-associated urinary tract infection in NICUs were Klebsiella sp and E.coli (56/156, 35.9%), carbapenem-resistant Gram-negative bacteria (CRGNB) (22/65, 33.9%), and CRGNB (11/36, 30.6%) respectively, while in PICUs, they were MRSA (53/169, 31.4%), CRGNB (50/87, 57.4%), Klebsiella sp and E.coli (18/52, 34.6%), respectively.

CONCLUSIONS

MDR Gram-negative bacteria (ESBL producers and carbapenem-resistant bacteria) were the most reported agents among MDR bacteria reported to Rio de Janeiro surveillance system. Except for CLABSI in children, they caused all device-associated infections in NICUs and PICUs.

Enterococcus faecalis CRISPR-Cas Is a Robust Barrier to Conjugative Antibiotic Resistance Dissemination in the Murine Intestine

CRISPR-Cas is a type of immune system in bacteria that is hypothesized to be a natural impediment to the spread of antibiotic resistance genes. In this study, we directly assessed the impact of CRISPR-Cas on antibiotic resistance dissemination in the mammalian intestine and under different in vitro conditions. We observed a robust effect of CRISPR-Cas on in vivo but not in vitro dissemination of antibiotic resistance plasmids in the native mammalian intestinal colonizer Enterococcus faecalis. We conclude that standard in vitro experiments currently do not appropriately model the in vivo conditions where antibiotic resistance dissemination occurs between E. faecalis strains in the intestine. Moreover, our results demonstrate that CRISPR-Cas present in native members of the mammalian intestinal microbiota can block the spread of antibiotic resistance plasmids.

CRISPR-Cas systems are barriers to horizontal gene transfer (HGT) in bacteria. Little is known about CRISPR-Cas interactions with conjugative plasmids, and studies investigating CRISPR-Cas/plasmid interactions in in vivo models relevant to infectious disease are lacking. These are significant gaps in knowledge because conjugative plasmids disseminate antibiotic resistance genes among pathogens in vivo, and it is essential to identify strategies to reduce the spread of these elements. We use enterococci as models to understand the interactions of CRISPR-Cas with conjugative plasmids. Enterococcus faecalis is a native colonizer of the mammalian intestine and harbors pheromone-responsive plasmids (PRPs). PRPs mediate inter- and intraspecies transfer of antibiotic resistance genes. We assessed E. faecalis CRISPR-Cas anti-PRP activity in the mouse intestine and under different in vitro conditions. We observed striking differences in CRISPR-Cas efficiency in vitro versus in vivo. With few exceptions, CRISPR-Cas blocked intestinal PRP dissemination, while in vitro, the PRP frequently escaped CRISPR-Cas defense. Our results further the understanding of CRISPR-Cas biology by demonstrating that standard in vitro experiments do not adequately model the in vivo antiplasmid activity of CRISPR-Cas. Additionally, our work identifies several variables that impact the apparent in vitro antiplasmid activity of CRISPR-Cas, including planktonic versus biofilm settings, different donor-to-recipient ratios, production of a plasmid-encoded bacteriocin, and the time point at which matings are sampled. Our results are clinically significant because they demonstrate that barriers to HGT encoded by normal (healthy) human microbiota can have significant impacts on in vivo antibiotic resistance dissemination.

IMPORTANCE CRISPR-Cas is a type of immune system in bacteria that is hypothesized to be a natural impediment to the spread of antibiotic resistance genes. In this study, we directly assessed the impact of CRISPR-Cas on antibiotic resistance dissemination in the mammalian intestine and under different in vitro conditions. We observed a robust effect of CRISPR-Cas on in vivo but not in vitro dissemination of antibiotic resistance plasmids in the native mammalian intestinal colonizer Enterococcus faecalis. We conclude that standard in vitro experiments currently do not appropriately model the in vivo conditions where antibiotic resistance dissemination occurs between E. faecalis strains in the intestine. Moreover, our results demonstrate that CRISPR-Cas present in native members of the mammalian intestinal microbiota can block the spread of antibiotic resistance plasmids.

Antimicrobial consumption in three pediatric and neonatal intensive care units in Saudi Arabia: 33-month surveillance study

Background

Despite their critical role in antimicrobial stewardship programs, data on antimicrobial consumption among the pediatric and neonatal population is limited internationally and lacking in Saudi Arabia. The current study was done as part of our antimicrobial stewardship activities.

Objectives

To calculate overall and type-specific antimicrobial consumption.

Methods

A prospective surveillance study was conducted at King Abdulaziz Medical City, Riyadh, Saudi Arabia, between October 2012 and June 2015 in two pediatric and one neonatal intensive care units (ICUs). Consumption data were collected manually on a daily basis by infection control practitioners. Data were presented as days of therapy (DOT) per 1000 patient-days and as frequency of daily consumption.

Results

During the 33 months of the study, a total of 30,110 DOTs were monitored during 4921 admissions contributing 62,606 patient-days. Cephalosporins represented 38.0% of monitored antimicrobials in pediatric ICUs followed by vancomycin (21.9%), carbapenems (14.0%), aminoglycosides (8.8%), and piperacillin/tazobactam (8.8%). Their consumption rates were 265.1, 152.6, 97.6, 61.4, and 61.4 DOTs per 1000 patient-days (respectively). Aminoglycosides represented 45.4% of monitored antimicrobials in neonatal ICU followed by cephalosporins (30.4%) vancomycin (13.6%), and carbapenems (8.3%). Their consumption rates were 147.5, 98.7, 44.3, and 27 DOTs per 1000 patient-days (respectively).

Conclusion

Cephalosporins are frequently used in pediatric ICU while aminoglycosides are frequently used in neonatal ICU. The local consumption of cephalosporins and carbapenems in both ICUs is probably higher than international levels. Such data can help in establishing and monitoring the functions of antimicrobial stewardship activities aiming to ensure judicious consumption of antimicrobials.

The Association Between the Developing Nasal Microbiota of Hospitalized Neonates and Staphylococcus aureus Colonization

Background

Hospitalized neonates are at high risk for invasive Staphylococcus aureus infections. S. aureus nasal colonization often precedes infection. The nasal microbiota may preclude or support colonization. We aimed to characterize and compare the nasal microbiota of hospitalized neonates who acquire S. aureus colonization (cases) and those who do not acquire S. aureus (controls).

Methods

We obtained residual nares samples from hospitalized neonates who were screened weekly for S. aureus nasal colonization and treated with intranasal mupirocin if colonized. Eight cases were matched based on chronologic age and systemic antibiotic exposure to 7 controls. We extracted DNA, sequenced the V3-V4 region of the 16s rRNA gene, and performed taxonomic assignments. The bacterial species richness, relative abundance, and in silico predicted gene content were compared between cases and controls at 7 days before S. aureus acquisition, at the time of acquisition, and 7 days after acquisition and treatment.

Results

Common commensals including nondiphtheriae corynebacteria were more abundant in the nares of controls and Rothia mucilaginosa was more abundant in cases 7 days after intranasal mupirocin treatment than in cases 7 days before S. aureus acquisition. Controls and treated cases had a higher predicted abundance of genes contributing to the synthesis of certain antimicrobial compounds than in cases before S. aureus acquisition.

Conclusions

Neonates without S. aureus nasal colonization had a higher abundance of bacterial species that antagonize S. aureus directly or by selecting for beneficial co-colonizers. These differences may inform novel S. aureus infection prevention strategies in high-risk infants.

Variation in use and outcomes related to midline catheters: results from a multicentre pilot study

Background

While midline vascular catheters are gaining popularity in clinical practice, patterns of use and outcomes related to these devices are not well known.

Methods

Trained abstractors collected data from medical records of hospitalised patients who received midline catheters in 12 hospitals. Device characteristics, patterns of use and outcomes were assessed at device removal or at 30 days. Rates of major (upper-extremity deep vein thrombosis [DVT], bloodstream infection [BSI] and catheter occlusion) and minor complications were assessed. χ² tests were used to examine differences in rates of complication by number of lumens, reasons for catheter removal l, and hospital-level differences in rates of midline use.

Results

Complete data on 1161 midlines representing 5%–72% of all midlines placed in participating hospitals between 1 January 2017 and 1 March 2018 were available. Most (70.8%) midlines were placed in general ward settings for difficult intravenous access (61.4%). The median dwell time of midlines across hospitals was 6 days; almost half (49%) were removed within 5 days of insertion. A major or minor complication occurred in 10.3% of midlines, with minor complications such as dislodgement, leaking and infiltration accounting for 71% of all adverse events. While rates of major complications including occlusion, upper-extremity DVT and BSI were low (2.2%, 1.4% and 0.3%, respectively), they were just as likely to lead to midline removal as minor complications (53.8% vs 52.5%, p=0.90). Across hospitals, absolute volume of midlines placed varied from 100 to 1837 devices, with corresponding utilisation rates of 0.97%–12.92% (p<0.001).

Conclusion

Midline use and outcomes vary widely across hospitals. Although rates of major complications are low, device removal as a result of adverse events is common.

Infection Prevention in Pediatric Oncology and Hematopoietic Stem Cell Transplant Recipients

Pediatric patients with malignancies and transplant recipients are at high risk of infection-related morbidity and mortality. Children at the highest risk for infections are those with acute myeloid leukemia (AML), relapsed acute lymphoblastic leukemia (ALL), and hematopoietic stem cell transplant recipients (HSCT). These patients are at high risk for life-threatening bacterial, viral, and fungal infections which are associated with prolonged hospital stay, poor quality of life, and increased healthcare cost and death. Recognition of risk factors which predisposes them to infections, early identification of signs and symptoms of infections, prompt diagnosis, and empiric/definitive treatment are the mainstay in reducing infection-related morbidity and mortality. Infection control and prevention programs also play a crucial role in preventing hospital-acquired infections in these immunosuppressed hosts.

Efficacy of β-phenylethylamine as a novel anti-microbial and application as a liquid catheter flush

With this study, we introduce a liquid flush for catheters and other tubing-based applications that consists of a solution of β-phenylethylamine (PEA) in tryptic soy broth. The initial experiments in multiwell polystyrene plates were conducted with Escherichia coli K-12 to assess the effectiveness of PEA at reducing planktonic growth, as well as the biomass and adenosine triphosphate (ATP) content of biofilm; PEA reduced these growth parameters as a function of increasing concentration. This effect was also seen in mutants of PEA catabolism, which leads us to believe that the PEA effect is due to PEA itself and not one of its degradation products. Since PEA reduced planktonic growth and biofilm when added at the time of inoculation, as well as at later time points, we propose PEA as a novel compound for the prevention and treatment of biofilm. PEA reduced planktonic growth and the ATP content of the biofilm for five bacterial pathogens, including an enterohemorrhagic E. coli, two uropathogenic E. coli, Pseudomonas aeruginosa and Staphylococcus aureus. A major finding of this study is the reduction of the ATP content of biofilm that formed in silicone tubing by periodic flushes of PEA. This experiment was performed to model antibiotic-lock treatment of an intravenous catheter. It was found that 10 mg ml^-1 of PEA reduced the ATP content of biofilm of five bacterial strains by 96.3 % or more after 2 weeks of incubation and three treatments with PEA. For P. aeruginosa, the reduction in ATP content was paralleled by an identical percentage reduction in viable cells in the biofilm.

Urinary Catheter-Associated Infections

Catheter-associated urinary tract infection remains one of the most prevalent, yet preventable, health care-associated infections. General prevention strategies include strict adherence to hand hygiene and antimicrobial stewardship. Duration of urinary catheterization is the most important modifiable risk factor. Targeted prevention strategies include limiting urinary catheter use; physician reminder systems, nurse-initiated discontinuation protocols, and automatic stop orders have successfully decreased catheter duration. Alternatives should be considered. If catheterization is necessary, proper aseptic practices for insertion and maintenance and closed catheter collection systems are essential for prevention. The use of bladder bundles and collaboratives aids in the effective implementation of prevention measures.

Epidemiology and risk factors for recurrent Staphylococcus aureus colonization following active surveillance and decolonization in the NICU

OBJECTIVES

To examine neonatal risk factors associated with recurrent Staphylococcus aureus colonization and to determine the genetic relatedness of S. aureus strains cultured from neonates before and after decolonization.Study designSingle-center retrospective cohort study of neonates admitted to the neonatal intensive care unit (NICU) from April 2013 to December 2015, during which weekly nasal cultures from hospitalized NICU patients were routinely obtained for S. aureus surveillance.

SETTING

Johns Hopkins Hospital's 45-bed level IV NICU in Baltimore, Maryland.

METHODS

Demographics and clinical data were collected on all neonates admitted to the NICU with S. aureus nasal colonization who underwent mupirocin-based decolonization during the study period. A decolonized neonate was defined as a neonate with ≥1 negative culture after intranasal mupirocin treatment. Pulsed-field gel electrophoresis was used for strain typing.

RESULTS

Of 2,060 infants screened for S. aureus, 271 (13%) were colonized, and 203 of these 271 (75%) received intranasal mupirocin. Of those treated, 162 (80%) had follow-up surveillance cultures, and 63 of these 162 infants (39%) developed recurrent colonization after treatment. The S. aureus strains were often genetically similar before and after decolonization. The presence of an endotracheal tube or nasal cannula/mask was associated with an increased risk of recurrent S. aureus colonization (hazard ratio [HR], 2.65; 95% confidence interval [CI], 1.19-5.90; and HR, 2.21; 95% CI, 1.02-4.75, respectively).

CONCLUSION

Strains identified before and after decolonization were often genetically similar, and the presence of invasive respiratory devices increased the risk of recurrent S. aureus nasal colonization in neonates. To improve decolonization efficacy, alternative strategies may be needed.

Establishing nationally representative central line-associated bloodstream infection surveillance data for paediatric patients in Greece

BACKGROUND

Healthcare-associated infections (HCAIs) are associated with increased morbidity and mortality and with excess costs. Central line-associated bloodstream infections (CLABSIs) are the most common HCAIs in neonates and children.

AIM

To establish national benchmark data for rates of CLABSI in neonatal and paediatric intensive care units (NICUs and PICUs) and paediatric oncology units (ONCs).

METHODS

Active surveillance for CLABSI was conducted from June 2016 to February 2017. A collaborative of 14 NICUs, four PICUs, and six ONCs participated in the programme. Surveillance definitions of central line (CL), central line utilization (CLU) ratio, CLABSI event, and CLABSI rate were based on the Centers for Disease Control and Prevention's 2014 National Healthcare Safety Network criteria. Medical records were assessed daily for calculating CL-days, patient-days, and susceptibility of isolated organisms.

FINDINGS

A total of 111 CLABSI episodes were recorded. The overall mean CLABSI rate was 4.41 infections per 1000 CL-days, and the CLU ratio was 0.31. CLABSI rates were 6.02 in NICUs, 6.09 in PICUs, and 2.78 per 1000 CL-days in ONCs. A total of 123 pathogens were isolated. The most common pathogens were Enterobacteriaceae (36%), followed by Gram-positive cocci (29%), non-fermenting Gram-negative bacteria (16%), and fungi (16%). Overall, 37% of Gram-negative pathogens were resistant to third-generation cephalosporins and 37% to carbapenems.

CONCLUSION

Nationally representative CLABSI rates were determined for paediatric patients. These data could be used to benchmark and serve as baseline data for the design and evaluation of infection control and antimicrobial stewardship interventions.

Lactobacillus paracasei CNCM I-3689 reduces vancomycin-resistant Enterococcus persistence and promotes Bacteroidetes resilience in the gut following antibiotic challenge

Enterococci, in particular vancomycin-resistant enterococci (VRE), are a leading cause of hospital-acquired infections. Promoting intestinal resistance against enterococci could reduce the risk of VRE infections. We investigated the effects of two Lactobacillus strains to prevent intestinal VRE. We used an intestinal colonisation mouse model based on an antibiotic-induced microbiota dysbiosis to mimic enterococci overgrowth and VRE persistence. Each Lactobacillus spp. was administered daily to mice starting one week before antibiotic treatment until two weeks after antibiotic and VRE inoculation. Of the two strains, Lactobacillus paracasei CNCM I-3689 decreased significantly VRE numbers in the feces demonstrating an improvement of the reduction of VRE. Longitudinal microbiota analysis showed that supplementation with L. paracasei CNCM I-3689 was associated with a better recovery of members of the phylum Bacteroidetes. Bile salt analysis and expression analysis of selected host genes revealed increased level of lithocholate and of ileal expression of camp (human LL-37) upon L. paracasei CNCM I-3689 supplementation. Although a direct effect of L. paracasei CNCM I-3689 on the VRE reduction was not ruled out, our data provide clues to possible anti-VRE mechanisms supporting an indirect anti-VRE effect through the gut microbiota. This work sustains non-antibiotic strategies against opportunistic enterococci after antibiotic-induced dysbiosis.

Salvage Strategy for Long-Term Central Venous Catheter-Associated Staphylococcus aureus Infections in Children

Introduction: Current international guidelines strongly recommend catheter removal in case of S. aureus central line-associated bloodstream infection (CLASBI), but a catheter salvage strategy may be considered in children given age-related specificities. No data is available regarding the outcome of this strategy in children. This study aims to evaluate catheter salvage strategy in children with S. aureus CLABSI, and to determine treatment failure rates and associated risk factors. Methods: We retrospectively analyzed data for all children <18 years having S. aureus CLABSI on a long-term central venous catheter in a tertiary hospital from 2010 to 2014. We defined catheter salvage strategy as a central venous catheter left in place ≥3 days after initiation of empiric treatment for suspected bacteremia, and catheter salvage strategy failure as the persistence or relapse of bacteremia with a S. aureus strain harboring the same antibiotic susceptibility pattern, or the occurrence or the worsening of local or systemic infectious complication between 72 h and 28 days after the first positive blood culture. Results: During the study period, 49 cases of S. aureus CLABSI on long-term central venous catheters were observed in 41 children (including 59% with long-term parenteral nutrition) and 6 (15%) isolates were resistant to methicillin. A catheter salvage strategy was chosen in 37/49 (76%) cases and failed in 12/37 (32%) cases. Initial presence of bloodstream co-infection, serum concentration of vancomycin under the targeted value and inadequate empiric treatment were significantly associated with catheter salvage therapy failure. Conclusions: The catheter salvage strategy of S. aureus CLABSI on a long-term central venous catheter was frequent in the studied hospital and failed only in one third of cases.