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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
12:18

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

Published on: February 9, 2011

Methicillin-resistant Staphylococcus aureus colonization and its association with infection among infants

Yhu-Chering Huang1, Yi-Hong Chou, Lin-Hui Su

  • 1Division of Pediatric Infectious Diseases, Chang Gung Children's Hospital, 5 Fu-Shin St, Kweishan, Taoyuan, Taiwan. ychuang@adm.cgmh.org.tw

Pediatrics
|August 3, 2006
PubMed
Abstract

Insights

Over 40% of hospitalized infants in endemic NICUs acquired methicillin-resistant Staphylococcus aureus (MRSA). MRSA colonization significantly increased infection risk, with most infections linked to prior MRSA colonization.

Area of Science:

  • Neonatal Intensive Care Unit (NICU) epidemiology
  • Infectious disease surveillance
  • Microbiology

Background:

  • Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant threat in healthcare settings.
  • NICUs are particularly vulnerable environments for the transmission of resistant bacteria.
  • Understanding MRSA colonization rates is crucial for infection control in neonates.

Purpose of the Study:

  • To determine the rate of MRSA colonization in hospitalized infants within endemic NICUs.
  • To investigate the association between MRSA colonization and subsequent MRSA infection in these infants.
  • To analyze the genetic relatedness of colonized and infected strains.

Main Methods:

  • Weekly surveillance cultures (nares, postauricular, axillae, umbilicus) from infants in NICUs over a 12-month period.
  • Detection of MRSA using culture methods.
  • Genotyping of MRSA isolates from colonized and infected infants using pulsed-field gel electrophoresis (PFGE) with Sma1 digestion.

Main Results:

  • MRSA colonization was detected in 323 out of 783 (41.3%) hospitalized infants.
  • Nares and umbilicus were the most common sites for initial MRSA colonization.
  • Infants with MRSA colonization had a significantly higher infection rate (26%) compared to non-colonized infants (2%).
  • 84 out of 92 infants with MRSA infections had prior MRSA colonization.
  • In 63 out of 68 cases, colonized and clinical MRSA isolates were indistinguishable by PFGE.

Conclusions:

  • A high prevalence of MRSA colonization exists among infants in endemic NICUs.
  • MRSA colonization is a significant risk factor for developing MRSA infection in hospitalized neonates.
  • The genetic similarity between colonized and infected strains suggests that colonization often precedes and leads to infection within the NICU setting.

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