title: A selected screening programme was less effective in the detection of methicillin-resistant Staphylococcus aureus colonisation in an orthopaedic unit.
abstract: OBJECTIVE
  Our unit has used a selective screening policy for methicillin-resistant Staphylococcus aureus (MRSA) colonisation using standard chromogenic growth media, based upon risk stratification. The aim of this study was to examine the effectiveness of this selective screening policy.
  
  
  METHODS
  A cohort of 429 patients was assessed for their risk status for MRSA colonisation using both rapid polymerase chain reaction (PCR) swabs and traditional culture and sensitivity analysis. The sensitivity, specificity, positive predictive values and negative predictive values of the traditional selective approach were calculated compared to universal rapid screening.
  
  
  RESULTS
  One hundred eighteen patients were considered high risk and would traditionally be further screened with standard culture of swabs. The prevalence of MRSA was 15/429 (3.5%). The sensitivity of selective screening was 53% identifying eight of 15 cases. The false-negative rate was therefore 47% and seven would have been missed. PCR results were available within four to six hours, whereas culture results were only available at 24 hours for the media showing no growth and not until 72 hours for positive MRSA cases.
  
  
  CONCLUSIONS
  We now advocate universal screening prior to, or on admission, using this rapid PCR test, as we consider this identifies MRSA colonisation more effectively and facilitates "ring-fencing" of orthopaedic beds.
authors.affiliation: Department of Orthopaedics, University of Edinburgh, Chancellor's Building, Royal Infirmary of Edinburgh, Old Dalkeith Road, EH16 4SB, Edinburgh, UK.
authors.forename: Jayshree
authors.initials: J
authors.lastname: Dave
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Jenkins
authors.forename: Alison
authors.initials: A
authors.lastname: Hardie
authors.forename: Melvyn
authors.initials: M
authors.lastname: Smith
authors.forename: Paul
authors.initials: P
authors.lastname: Gaston
authors.forename: Alan P
authors.initials: AP
authors.lastname: Gibb
authors.forename: Kate
authors.initials: K
authors.lastname: Templeton
authors.forename: Alastair H
authors.initials: AH
authors.lastname: Simpson
mesh_terms: D015331:Cohort Studies; D003362:Cost-Benefit Analysis; D004269:DNA, Bacterial / Q000235:genetics; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006757:Hospital Units; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods* / Q000592:standards*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics / Q000302:isolation & purification; D008828:Microbiological Techniques / Q000191:economics; D009985:Orthopedics; D016133:Polymerase Chain Reaction / Q000191:economics; D015995:Prevalence; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial