Resistance to methicillin in isolates of Staphylococcus aureus from blood and cerebrospinal fluid in Wales, 1993-1997

Surveillance data for organisms isolated from blood cultures and cerebrospi nal fluid (CSF) specimens has been gathered electronically in Wales since 1 993. Over this period the proportion of total reported organisms from blood cultures and CSF represented by methicillin-resistant staphylococci (MRSA) has risen steadily. This has corresponded to a rise in rates of methicilli n resistance amongst Staphylococcus aureus isolated from blood cultures and CSF from 4 to 43%. In certain age/gender groups in 1997, more than 50% of isolates of S. aureus were resistant to methicillin, suggesting that a chan ge in empirical treatment may be necessary for suspected staphylococcal sep sis.