MRSA Colonization and Risk of Infection in the Neonatal and Pediatric ICU: A Meta-analysis

Abstract

BACKGROUND AND OBJECTIVE: Methicillin-resistant Staphylococcus aureus (MRSA) is a significant cause of morbidity and mortality in NICUs and PICUs. Our objective was to assess the burden of MRSA colonization on admission, study the time trends, and examine the significance of MRSA colonization in this population. METHODS:PubMed and Embase databases were consulted. Studies that reported prevalence of MRSA colonization on ICU admission were selected. Two authors independently extracted data on MRSA colonization and infection. RESULTS:We identified 18 suitable articles and found an overall prevalence of MRSA colonization of 1.9% (95% confidence interval [CI] 1.3%-2.6%) on admission to the NICU or PICU, with a stable trend over the past 12 years. Interestingly, 5.8% (95% CI 1.9%-11.4%) of outborn neonates were colonized with MRSA on admission to NICU, compared with just 0.2% (95% CI 0.0%-0.9%) of inborn neonates (P = .01). The pooled acquisition rate of MRSA colonization was 4.1% (95% CI 1.2%-8.6%) during the NICU and PICU stay and was as high as 6.1% (95% CI 2.8%-10.6%) when the NICU population was studied alone. There was a relative risk of 24.2 (95% CI 8.9-66.0) for colonized patients to develop a MRSA infection during hospitalization. CONCLUSIONS:In the NICU and PICU, there are carriers of MRSA on admission, and MRSA colonization in the NICU is almost exclusively associated with outborn neonates. Importantly, despite infection control measures, the acquisition rate is high, and patients colonized with MRSA on admission are more likely to suffer a MRSA infection during hospitalization.

Methicillin-resistant Staphylococcus aureus nasal colonization in a level III neonatal intensive care unit: Incidence and risk factors

“…A recent meta-analysis shows, indeed, a significantly higher colonization rate among outborn infants, a plausible consequence of their older age and more prolonged exposure to the health care setting. 3 In addition, about 50% of infants testing positive at their first nasal swab had been transferred from the nursery. MRSA transmission is already known to be highly efficient in nurseries due to the routine care practices and a lower awareness by HCWs of general infection control measures.…”

“…Of these, 117 (53.92%) tested positive at the time of their first sampling, whereas the remaining 100 (46.08%) acquired MRSA later during their NICU stay. The interval of time between admission and collection of the first nasal swab from the NICU infants did not differ significantly between the 2 subgroups (4 [2][3][4][5][6] days for those with the first swab positive vs 3 [1.5-6.5] days for those with the first swab negative; P ¼ .10). Table 2 shows the differential characteristics of the 2 subgroups of patientsdMRSA colonized and noncolonizeddat their first nasal sampling, at the NICU admission.…”

“…2 In adult patients, MRSA infections are becoming less common, whereas infections in neonatal intensive care units (NICUs) seem to be becoming more frequent. 3 Aggressive measures can be necessary to contain the outbreaks, frequently in the form of bundle strategies. 4 However, in highly endemic areas, despite these measures being rigorously enforced, ongoing MRSA transmission and infection have been recorded for many years.…”

“…5 Colonized neonates play a major role as endogenous reservoirs of MRSA in NICU settings. 3 Consequently, active surveillance culture (ASC) programs can be instituted to identify colonized patients and obtain otherwise unavailable information helpful to control MRSA transmission. 3,4 We recently reported the epidemiologic characteristics and the temporal trend of the endemic MRSA colonization in the level III NICU of the Azienda Ospedaliera Universitaria Policlinico (AOUP) "P. Giaccone," Palermo, Italy, during the period June 2009-June 2012.…”

“…3 Consequently, active surveillance culture (ASC) programs can be instituted to identify colonized patients and obtain otherwise unavailable information helpful to control MRSA transmission. 3,4 We recently reported the epidemiologic characteristics and the temporal trend of the endemic MRSA colonization in the level III NICU of the Azienda Ospedaliera Universitaria Policlinico (AOUP) "P. Giaccone," Palermo, Italy, during the period June 2009-June 2012. 6 The purpose of our study was to describe risk factors for MRSA acquisition in this NICU during the 4-year period June 2009-June 2013.…”