Original Article

Korean J Clin Pathol 1991; 11(1): 131-134

Published online February 1, 1991

Copyright © Korean Society for Laboratory Medicine.

Penicillin Resistance in Streptococcus pneumoniae

Mee Na Kim, M.D., Chik Hyun Pai, M.D.

Department of Clinical Pathology, Asan Medical Center College of Medicine, University of Ulsan


Background :In order to assess the prevalence of penicillin-resistant pneumococci we screened of penicillin susceptibility of 72 strains isolated at Asan Medical Center between June 1989 and August 1990. Eighteen( 25 %) of the 72 strains were shown to be resistant to penicillin by the oxacillin disk diffusion method recommended by NCCLS. These included 6 strains from blood and body fluid, 7 from sputum and 5 from other specimens. Seven penicillin-resistant and 8 penicillin-susceptible strains as determined by the oxacillin disk diffusion method were further examined for penicillin MIC by the broth dilution method. The results showed a complete agreement between the two method; the 8 susceptible strains had MIC`s of 10.06 ,&ml and the 7 resistant strains MIC`s between 0.25 and 2 pug/ml. Of a particular significance was the finding that 3 of the 7 resistant strains were shown to have a high-level resistance to penicillin (MIC; 2 2.0 M/ml). Furthermore, 2 of the 3 highly resistant strains were among the blood and CSF isolates. It is highly recommended that all significant pneumococcal isolates should be screened for penicillin susceptibility by the oxacillin disk diffusion method, followed by MIC test of strains showing resistance to penicillin Method : Result : Conclusion :

Keywords: Streptococcus pneumoniae Penicillin, Antimicrobial resistance, Prevalence