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?
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%.
Becker
Karsten
K
University of Münster, Institute of Medical Microbiology, D-48149 Münster. kbecker@uni-muenster.de.
Pagnier
Isabelle
I
Schuhen
Brigitte
B
Wenzelburger
Frauke
F
Friedrich
Alexander W
AW
Kipp
Frank
F
Peters
Georg
G
von Eiff
Christof
C
D001426:Bacterial Proteins; D003030:Coagulase / Q000378:metabolism*; D005189:False Positive Reactions; D006801:Humans; D008712:Methicillin / Q000494:pharmacology*; D016106:Methicillin Resistance / Q000235:genetics*; D009666:Nose / Q000382:microbiology*; D046915:Penicillin-Binding Proteins; D011237:Predictive Value of Tests; D013203:Staphylococcal Infections / Q000175:diagnosis* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification
D001426:Bacterial Proteins; D003030:Coagulase; D046915:Penicillin-Binding Proteins; C487789:mecA protein, Staphylococcus aureus; D008712:Methicillin