Antimicrobial resistance in Streptococcus pneumoniae: a decade of results from south-western Sydney.

We report the emerging drug-resistance in Streptococcus pneumoniae seen by the South Western Area Pathology Service (SWAPS) from 1 January 1990 to 31 July 2000. SWAPS performs all the pathology testing for the public hospitals in the South Western Sydney Area Health Service, which serves a population of 700,000; 120,000 separations occur at these hospitals annually. In all, 2,265 patients submitted specimens yielding S. pneumoniae. These included respiratory tract specimens, blood cultures, eye swabs and cerebrospinal fluid (CSF). Resistance to penicillin, cefotaxime, and non-beta-lactam antibiotics, especially cotrimoxazole, has emerged over the 1990s. From 1997 onwards, around 10 per cent of CSF and blood culture isolates demonstrated penicillin-resistance and 5 per cent showed cefotaxime-resistance. In 2000, 35 per cent of pneumococci from sites other than CSF and blood exhibited resistance to penicillin and 15 per cent showed resistance to cefotaxime. Resistance to other agents also increased over the decade. In 2000, 76 per cent of all isolates were resistant to cotrimoxazole, 26 per cent to erythromycin and 24 per cent to tetracyclines. Rifampicin-resistance was negligible over the decade, and vancomycin-resistance was absent. Antibiotics currently used for empirical treatment of certain S. pneumoniae infections may now need to be reviewed.