Background: The emergence and dissemination of resistance to penicillin among Streptococcus pneumoniae changed the approach to empiric antimicrobial therapy.
Aim: To evaluate the in vitro susceptibility to penicillin in all S. pneumoniae strains isolated in Puerto Montt Hospital between 1995 and 2003.
Material and methods: We revised all Microbiology Laboratory files of this period. Identification and antimicrobial susceptibility study methods for S pneumoniae did not change during the study period.
Results: Six hundred eighteen S pneumoniae strains were identified. Of these, 66% came from adults and 48% from invasive diseases. Only 1.9% of strains were penicillin resistant and 7.6% had intermediate sensibility. Strains isolated from children and those isolated from non sterile sources had non significantly higher resistance levels. The susceptibility did not change along the years of the study.
Conclusions: Among S pneumoniae strains isolated at Puerto Montt Hospital, the prevalence of penicillin resistance is low.