Unrecognized burden of methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus carriage in the pediatric intensive care unit

Impact of environmental cleaning on the colonization and infection rates of multidrug-resistant Acinetobacter baumannii in patients within the intensive care unit in a tertiary hospital

Objective

To continuously evaluate the effect of environmental cleaning and hand hygiene compliance on the colonization and infection rates of multidrug-resistant Acinetobacter baumannii (MDR-AB) in the patients within an intensive care unit (ICU).

Methods

Environmental cleaning on the high-touch clinical surfaces (HTCS) within a comprehensive ICU was evaluated through monitoring fluorescent marks when the overall compliance with hand hygiene during 2013–2014 was monitored. Meanwhile, samples from the HTCS and inpatients were collected and sent for bacterial culture and identification. The drug susceptibility testing was further implemented to monitor the prevalence of MDR-AB. The genetic relatedness of MDR-AB collected either from the HTCS or inpatients was analyzed by pulsed field gel electrophoresis (PFGE) when an outbreak was doubted.

Results

The overall compliance with hand hygiene remained relatively stable during 2013–2014. Under this circumstance, the clearance rate of fluorescence marks on the environmental surfaces within ICUs significantly increased from 21.9 to 85.7%, and accordingly the colonization and infection rates of MDR-AB decreased from 16.5 to 6.6‰ and from 7.4 to 2.8‰, respectively, from the beginning to the end of 2013. However, during 2014, because of frequent change and movement of environmental services staff, the clearance rate of fluorescence marks decreased below 50.0%, and the overall colonization and infection rates of MDR-AB correspondingly increased from 9.1 to 11.1‰ and from 1.5 to 3.9‰, respectively. PFGE displayed a high genetic relatedness between the MDR-AB strains analyzed, indicating a dissemination of MDR-AB during the surveillance period.

Conclusion

For the easily disseminated MDR-AB within ICUs, the clearance rate of fluorescence labeling on HTCS is negatively correlated with the hospital infection rate of MDR-AB. Such an invisible fluorescence labelling is an effective and convenient method to continuously monitor cleanness of medical environment within hospitals.

Vancomycin-resistant enterococci colonisation, risk factors and risk for infection among hospitalised paediatric patients: a systematic review and meta-analysis

The objective of this study was to estimate the rate and significance of colonisation with vancomycin-resistant enterococci (VRE) among hospitalised children. The PubMed and EMBASE databases were systematically searched (last accessed on 29 May 2016) to identify studies evaluating VRE colonisation of the gastrointestinal tract of hospitalised children in non-outbreak periods. Of 945 non-duplicate citations, 19 studies enrolling 20 234 children were included. The overall and paediatric intensive care unit (PICU) rate of VRE colonisation were both 5% [95% confidence interval (CI) 3-8% overall and 95% CI 2-9% in the PICU] but was 23% in haematology/oncology units (95% CI 18-29%). Studies that were exclusively performed in haematology/oncology units reported significantly higher rates compared with all other studies in the univariate and multivariate analyses (P = 0.001). Previous vancomycin [risk ratio (RR) = 4.34, 95% CI 2.77-6.82] or ceftazidime (RR = 4.15, 95% CI 2.69-6.40) use was a risk factor for VRE colonisation. Importantly, VRE colonisation increased the risk of subsequent VRE infection (RR = 8.75, 95% CI 3.19-23.97). In conclusion, a high rate of VRE colonisation was found among hospitalised children in institutions that performed targeted screening. Importantly, colonised children were almost 9 times more likely to develop subsequent VRE infection. Judicious use of specific antibiotics along with intensification of infection control measures should be considered in high-prevalence institutions. Also, the high incidence of VRE colonisation among children with haematological/oncological diseases identifies a high-risk population.

Regional Epidemiology of Methicillin-Resistant Staphylococcus aureus Among Critically Ill Children in a State With Mandated Active Surveillance

BACKGROUND

In theory, active surveillance of methicillin-resistant Staphylococcus aureus (MRSA) reduces MRSA spread by identifying all MRSA-colonized patients and placing them under contact precautions. In October 2007, Illinois mandated active MRSA surveillance in all intensive care units, including neonatal intensive care units (NICUs) and pediatric intensive care units (PICUs). We evaluated MRSA trends in a large metropolitan region in the wake of this law.

METHODS

Chicago hospitals with a NICU or PICU were recruited for 8 single-day point prevalence surveys that occurred twice-yearly between June 2008 and July 2011 and then yearly in 2012 to 2013. Samples from all patients were cultured for MRSA (nose and umbilicus for neonates, nose and groin for pediatric patients). Hospital-reported admission MRSA-screening results also were obtained. Point prevalence cultures were screened for MRSA by using broth enrichment, chromogenic agar, and standard confirmatory methods.

RESULTS

All eligible hospitals (N = 10) participated (10 NICUs, 6 PICUs). Hospital-reported adherence to state-mandated MRSA screening at admission was high (95% for NICUs, 94% for PICUs). From serial point prevalence surveys, overall MRSA prevalences in the NICUs and PICUs were 4.2% (89 of 2101) and 5.7% (36 of 632), respectively. MRSA colonization prevalences were unchanged in the NICUs (year-over-year risk ratio [RR], 0.93 [95% confidence interval (CI), 0.78-1.12]; P = .45) and trended toward an increase in the PICUs (RR, 1.25 [95% CI, 0.72-2.12]; P = .053). We estimated that 81% and 40% of MRSA-positive patients in the NICUs and PICUs, respectively, had newly acquired MRSA.

CONCLUSIONS

In a region with mandated active MRSA surveillance, we found ongoing unchanged rates of MRSA colonization and acquisition among NICU and PICU patients.

Targeted Surveillance to Identify Children Colonized with Vancomycin-Resistant Enterococcus in the Pediatric Intensive Care Unit

Performing admission surveillance cultures is a resource-intensive strategy to identify asymptomatic patients with vancomycin-resistant Enterococcus (VRE) colonization. We measured VRE prevalence among children admitted to the pediatric intensive care unit. Targeted surveillance captured 94% of VRE-colonized children and may be an effective strategy to identify VRE carriers and facilitate pediatric infection prevention strategies.

Methicillin-resistant Staphylococcus aureus in patients with congenital heart disease in the pediatric intensive care unit

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) colonization has been recognized as a significant problem among hospitalized patients. Available data about prevalence of MRSA among children with congenital heart disease (CHD) are minimal. The aim of the study was to determine the prevalence of MRSA colonization and to identify risk factors for MRSA colonization among children <19 years old with CHD admitted to a pediatric intensive care unit (PICU).

METHODS

Admission and weekly MRSA nasal surveillance testing was performed, and patients were stratified into six risk groups based on the Risk Adjustment for Congenital Heart Surgery-1 Method. The MRSA-colonized children were compared to the MRSA noncolonized children.

RESULTS

During the 3-year study period, there were 372 admissions of children with CHD to the PICU. Of the 372, 72 (19.4%) had no surveillance cultures performed or had no prior history of MRSA and were excluded from further analysis. Of the remaining 300 admissions, 29 (9.7%) (263 individual children) were found to be colonized. The mean age of the 263 children when first admitted to the PICU was 3.29 years (range 0.03-18.30, median 0.66). Age distribution was not significantly different between the colonized and noncolonized groups (P = .236). Gender (P = .667), race (P = .837), and CHD complexity (P = .395) were not significantly associated with colonization. The odds of being colonized if previously hospitalized were 4.42 times greater than if not previously hospitalized (95% confidence interval 1.89, 10.34).

CONCLUSION

Routine MRSA surveillance should be performed in patients with CHD to identify colonized patients.

Postdischarge surveillance to identify subsequent methicillin-resistant Staphylococcus aureus infections in colonized children

Some hospitals screen and identify high risk patients for methicillin-resistant Staphylococcus aureus (MRSA) colonization. We performed postdischarge surveillance, including a telephone survey, and estimated a 9.5% incidence of infection in MRSA-colonized children in the year following discharge. Interventions are needed to reduce MRSA infections in colonized children after hospital discharge.

Methicillin-resistant Staphylococcus aureus colonization in a pediatric intensive care unit: risk factors

BACKGROUND

Both methicillin-resistant Staphylococcus aureus (MRSA) and penicillin-resistant Streptococcus pneumoniae have become significant causes of disease, both in health care and community settings.

OBJECTIVES

All patients admitted to our pediatric intensive care unit (PICU) currently had a rapid test for methicillin-resistant Staphylococcus aureus (MRSA) performed as per hospital guidelines. This study looked at risk factors for colonization.

METHODS

Nasal swabs were tested for MRSA on all admissions to the PICU from May 2008 to September 2009 using polymerase chain reaction as per hospital guidelines. All patients enrolled were placed in either a MRSA-positive or a MRSA-negative group, which were compared with each other. Risk factors were assessed from a questionnaire and the resident history.

RESULTS

The prevalence of MRSA colonization in our study was 4.5%. Six hundred sixty-six patients were negative for MRSA, and 31 were positive. Patients in the MRSA colonization group were younger, more likely had family (household members) employed in medicine, and were more likely hospitalized or had undergone surgery within the previous 12 months. Prolonged neonatal intensive care unit stay (>1 week) was associated with MRSA colonization (P < .001).

CONCLUSION

The percentage of patients positive for MRSA admitted to a PICU is low. Recent exposure to the health care system, especially a stay in the neonatal intensive care unit, is associated with an increased risk of colonization.

Methicillin-resistant Staphylococcus aureus colonization and risk of subsequent infection in critically ill children: importance of preventing nosocomial methicillin-resistant Staphylococcus aureus transmission

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) colonization is a predictor of subsequent infection in hospitalized adults. The risk of subsequent MRSA infections in hospitalized children colonized with MRSA is unknown.

METHODS

Children admitted to an academic medical center's pediatric intensive care unit between March 2007 and March 2010 were included in the study. Anterior naris swabs were cultured to identify children with MRSA colonization at admission. Laboratory databases were queried and National Healthcare Safety Network definitions applied to identify patients with MRSA infections during their hospitalization or after discharge.

RESULTS

The MRSA admission prevalence among 3140 children was 4.9%. Overall, 56 children (1.8%) developed an MRSA infection, including 13 (8.5%) colonized on admission and 43 (1.4%) not colonized on admission (relative risk [RR], 5.9; 95% confidence interval [CI], 3.4-10.1). Of those, 10 children (0.3%) developed an MRSA infection during their hospitalization, including 3 of 153 children (1.9%) colonized on admission and 7 of 2987 children (0.2%) not colonized on admission (RR, 8.4; 95% CI, 2.7-25.8). African-Americans and those with public health insurance were more likely to get a subsequent infection (P < .01 and P = .03, respectively). We found that 15 children acquired MRSA colonization in the pediatric intensive care unit, and 7 (47%) developed a subsequent MRSA infection.

CONCLUSIONS

MRSA colonization is a risk factor for subsequent MRSA infection in children. Although MRSA colonized children may have lower risks of subsequent infection than adults, children who acquire MRSA in the hospital have similarly high rates of infection. Preventing transmission of MRSA in hospitalized children should remain a priority.

Active surveillance culturing impacts methicillin-resistant Staphylococcus aureus acquisition in a pediatric intensive care unit

OBJECTIVE

To determine whether active surveillance culturing for methicillin-resistant Staphylococcus aureus (MRSA) decreases nosocomial MRSA acquisition in the pediatric intensive care unit.

DESIGN

Before and after observational study.

SETTING

A tertiary care, 20-bed, pediatric intensive care unit.

PATIENTS

All patients admitted to the pediatric intensive care unit.

INTERVENTIONS

Anterior nares cultures for MRSA were obtained on admission and weekly in the pediatric intensive care unit from January 2007 to December 2009 as part of a hospital quality improvement project.

MEASUREMENTS AND MAIN RESULTS

MRSA admission prevalence and nosocomial incidence density were determined retrospectively for 2006 and prospectively for 2007-2009. Nosocomial MRSA incidence density during the intervention period was determined monthly and analyzed by trend analysis by using a general linear model. The correlation of active surveillance culturing compliance with nosocomial acquisition of MRSA was analyzed. Possible confounding by healthcare worker hand hygiene compliance observed during the intervention period was also analyzed by multivariate linear regression analysis. The yearly MRSA incidence density significantly decreased from 2006 to 2009 (6.88 per 1,000 patient days to 1.45 per 1,000 patient days, p < .001) and from 2007 to 2009 (7.32 per 1,000 patient days to 1.45 per 1,000 patient days, p < .001). Trend analysis demonstrated a significant decline in MRSA acquisition over time following the introduction of active surveillance culturing (p < .001). Surveillance culturing was significantly associated with the decline in MRSA acquisition observed in the pediatric intensive care unit by multivariate regression analysis when controlling for hand hygiene (p = .01).

CONCLUSIONS

Active surveillance culturing resulted in significantly decreased nosocomial acquisition of MRSA in a pediatric intensive care unit setting. Admission and weekly active surveillance culturing appears to be an effective tool to decrease the spread of MRSA in the pediatric intensive care unit, independent of improvement in hand hygiene compliance. The impact on hospital-acquired MRSA infections and the cost benefit of active surveillance culturing require further study.

The past, present, and future of healthcare‐associated infection prevention in pediatrics: multidrug‐resistant organisms

Multidrug resistant organisms (MDROs) and healthcare&#x2010;associated infections (HAIs) are associated with increased lengths of hospital stay, increased costs, and increased mortality. We explore the scope of MDRO HAIs in children, current MDRO HAI prevention practices and data to support these practices, and we propose research topics targeting MDRO HAI prevention in children.

Nosocomial infections and multidrug-resistant bacterial organisms in the pediatric intensive care unit

Nosocomial infections in Pediatric Intensive Care Units (PICUs) caused by multidrug-resistant bacterial organisms are increasing. This review attempts to report on significant findings in the current literature related to nosocomial infections in PICU settings with an international perspective. The types of nosocomial infections are addressed, including catheter-related bloodstream infections, ventilator-associated pneumonia, urinary tract infections, gastrointestinal infections and post-surgical wound infections. A review of emerging resistant bacterial pathogens includes methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus sp., Clostridium difficile, extended-spectrum β-lactamase producing Gram-negative organisms, Klebsiella pneumoniae carbapenemase-producing strains and multi-drug resistant Acinetobacter baumannii. Basic and enhanced infection control methods for the management and control of multidrug-resistant organisms are also summarized with an emphasis on prevention.

Prevention of healthcare-associated infections in children: new strategies and success stories

PURPOSE OF REVIEW

Attention to patient safety has made hospital infection prevention and control strategies a subject of increasing focus from healthcare personnel, patients and families, accrediting organizations, and government. This review highlights recent literature and new successes in the prevention of healthcare-associated infections in children.

RECENT FINDINGS

Emerging evidence about risk factors for various healthcare-associated infections in children will help target available adjunctive preventive interventions. Multicenter pediatric collaborative efforts to emphasize best practices have resulted in decreases in infection rates, particularly for central line-associated bloodstream infections. A low prevalence of colonization or infection with multidrug-resistant organisms in hospitalized children, combined with a lack of compelling evidence of effectiveness for active surveillance and decolonization, have made decisions about routine screening challenging.

SUMMARY

A renewed interest in infection prevention by multiple stakeholders has energized our field and contributed to impressive successes in reducing rates of healthcare-associated infections. Nevertheless, important knowledge gaps remain and an emphasis on funding of high-quality, rigorous studies to answer unresolved questions will be critical to our efforts to further prevent infections for hospitalized children.

Community-associated methicillin-resistant Staphylococcus aureus strains in pediatric intensive care unit

Virulent community-associated methicillin-resistant Staphylococcus-aureus (CA-MRSA) strains have spread rapidly in the United States. To characterize the degree to which CA-MRSA strains are imported into and transmitted in pediatric intensive care units (PICU), we performed a retrospective study of children admitted to The Johns Hopkins Hospital PICU, March 1, 2007-May 31, 2008. We found that 72 (6%) of 1,674 PICU patients were colonized with MRSA. MRSA-colonized patients were more likely to be younger (median age 3 years vs. 5 years; p = 0.02) and African American (p<0.001) and to have been hospitalized within 12 months (p<0.001) than were noncolonized patients. MRSA isolates from 66 (92%) colonized patients were fingerprinted; 40 (61%) were genotypically CA-MRSA strains. CA-MRSA strains were isolated from 50% of patients who became colonized with MRSA and caused the only hospital-acquired MRSA catheter-associated bloodstream infection in the cohort. Epidemic CA-MRSA strains are becoming endemic to PICUs, can be transmitted to hospitalized children, and can cause invasive hospital-acquired infections. Further appraisal of MRSA control is needed.

Genomic variation and evolution of Staphylococcus aureus

The evolution of new human and animal pathogenic strains of Staphylococcus aureus has been due to the accumulation of mobile genetic elements (MGE) encoding methicillin resistance and virulence factors into successful lineages. These include epidemic methicillin-resistant S. aureus in hospitals (EMRSA), community-associated MRSA (CA-MRSA), fully vancomycin-resistant MRSA (VRSA) and livestock-associated MRSA (LA-MRSA). The S. aureus population in humans is dominated by about ten S. aureus lineages while animals generally have different lineages. Individual isolates within each lineage have unique combination of MGE often encoding virulence and resistance genes. S. aureus evolves due to point mutation and selection, but also dramatically due to the horizontal transfer of these MGE between strains or from other species or genera. Horizontal transfer, by conjugation or transduction, can be blocked by S. aureus restriction modification systems which are lineage specific. Because of the mobility of MGE, there are prospects for increasingly virulent and resistant strains to emerge that could severely affect healthcare and agriculture more effectively than the current pathogens.