[Penicillin-resistant pneumococcus: practical implications]

Abstract

OBJECTIVE: To review epidemiological, laboratorial and clinical aspects of the penicillin-resistant pneumococcus, and to consider the impact of the rapidly increasing drug-resistance on the management of the main infections caused by these pathogens. METHODS: Bibliographic review covering the last ten years, using both Medline system and direct research. RESULTS AND CONCLUSIONS: The Streptococcus pneumoniae is an important agent in acute otitis media, pneumonia and meningitis in children. The clinical evaluation of the pneumococcal infections depends on the age and health condition of the patient, site and severity of the infection and the adequacy of the treatment. Penicillin was uniformly effective against pneumococcus until three decades ago, when the first reports of clinical resistance were published. Since then, there has been a rapidly increasing in the level and rates of resistance to penicillin, which parallels to others beta lactams and antimicrobials. This paper includes a suscint review of the genetic and phenotypic mechanisms of the resistance to penicillin, the available bacteriologic tests for determination of in vitro susceptibility to antimicrobials and finally the importance of the pneumococcus in acute otitis media, pneumonia/bacteremia and meningitis. There has been new empirical therapeutic regimens recommended for meningitis, according to the community rates and levels of resistance to beta lactams and to the presence of certain underlying conditions among the patients, such as immunedepressant diseases and frequent antibiotic consumption. The rapidly increasing prevalence of drug-resistant strains emphasizes the importance of judicious antibiotic use and the development of a conjugate vaccine, effective to prevent invasive infections and to reduce the rate of carriage of the pneumococcus, even among infants.