Evaluation of oxacillin disk test for screening Streptococcus pneumoniae by penicillin Etest method / 国际检验医学杂志

ABSTRACT

Objective To evaluate the oxacillin disk screening test for screening Streptococcus pneumoniae by the penicillin Etest method.Methods 96 clinically isolated non-meningitis strains of Streptococcus pneumoniae were collected.The sensitivity and spe-cificity of the oxacillin disc screening test was evaluated by the penicillin Etest method as a standard method for detecting the peni-cillin susceptibility.Results Among 96 non-meningitis strains of Streptococcus pneumoniae,the penicillin-susceptible Streptococcus pneumoniae(PSSP)strains detected by the penicillin Etest method accounted for 96.9%(93/96),the penicillin intermediate Strep-tococcus pneumoniae(PISP)strains accounted for 3.1%(3/96)and no penicillin resistant Streptococcus pneumoniae(PRSP)strain was found.But 16 PSSP strains were detected by the oxacillin disc screening test with the sensitivity of 17.2% and the specificity of 100.0%,respectively.The difference between the oxacillin disc screening test and the penicillin Etest method was statistically sig-nificant(χ2 =77,P <0.01 ).Conclusion The oxacillin disc screening test has the low sensitivity for preliminarily screening non-meningitis strains of Streptococcus pneumoniae.Most of Streptococcus pneumoniae must be detected by the minimum inhibitory concentration(MIC)methods such as the penicillin Etest method.