Antimicrobial resistance and severe infections

Since many years, the antimicrobial resistance increases as well as for com munity-acquired as for nosocomial infections. Antibiotic-resistant pneumoco cci are neither more nor less virulent susceptible strains. Except for immu nocompromised patients, the outcome of penicillin-resistant pneumococcal in fections have been similar to those in patients who are infected by suscept ible ones. Current levels of S. pneumoniae resistance to penicillin and cep halosporin are not associated to an increase in mortality in children with meningitis if adequate doses of antibiotics are given. Because empiric ther apy has changed, antibiotic resistance has not been associated with increas ed mortality. This statement can be extended to Meningococcus, for which 32 to 50 % of the strains have a decreased susceptibility to penicillin. For nosocomial infections, S. aureus is the main studied pathogen. Several stud ies report that in patients with severe diseases (bacteremia or pneumonia) methicillin resistance of S. aureus had no significant impact on patient ou tcome after adjustement for different confounders. The main risk factor for mortality is the severe underlying diseases rather than the resistance as well for methicillin -resistant S.aureus, as for vancomycin resistant enter ococci, Klebsiella with extended spectrum beta lactamase and Enterobacters. Recommendations for controlling epidemiologic surveillance, using barrier precautions and limiting the use of antibiotics as well in the hospital as in the community must be undertaken. (C) 2001 Editions scientifiques et med icales Elsevier SAS.