Does nasal cocolonization by methicillin-resistant coagulase-negative staphylococci and methicillin-susceptible Staphylococcus aureus strains occur frequently enough to represent a risk of false-positive methicillin-resistant S. aureus determinations by molecular methods?

J Clin Microbiol. 2006 Jan;44(1):229-31. doi: 10.1128/JCM.44.1.229-231.2006.

Abstract

By analyzing the colonization of the anterior nares in cardiothoracic surgery patients on admission, nasal cocolonization by methicillin-susceptible Staphylococcus aureus and methicillin-resistant coagulase-negative staphylococci was detected in 8/235 (3.4%) specimens. Consequently, in a low-methicillin-resistant S. aureus (MRSA) setting, a molecular MRSA screening test targeting the mecA gene and an S. aureus-specific gene in parallel and applied directly to clinical specimens would be associated with an unacceptable positive predictive value of about 40%.

MeSH terms

  • Bacterial Proteins
  • Coagulase / metabolism*
  • False Positive Reactions
  • Humans
  • Methicillin / pharmacology*
  • Methicillin Resistance / genetics*
  • Nose / microbiology*
  • Penicillin-Binding Proteins
  • Predictive Value of Tests
  • Staphylococcal Infections / diagnosis*
  • Staphylococcal Infections / microbiology
  • Staphylococcus aureus / drug effects*
  • Staphylococcus aureus / enzymology
  • Staphylococcus aureus / genetics
  • Staphylococcus aureus / isolation & purification

Substances

  • Bacterial Proteins
  • Coagulase
  • Penicillin-Binding Proteins
  • mecA protein, Staphylococcus aureus
  • Methicillin