Clinical diagnosis of primary syphilis made in an STI outpatient clinic versus that made by the T. pallidum real-time PCRa

T. pallidum real-time PCR resultNo. of cases with the following clinical diagnosis at STI clinicb:
  • a The data are for a total of 716 cases. The sensitivity of the T. pallidum real-time PCR was 72.8%, the specificity was 95.5%, the PPV was 89.2%, and the NPV was 95.0%. The kappa value was 0.769, which indicates good agreement between the results of the two tests.

  • b The diagnostic criteria for primary syphilis in the STI outpatient clinic setting were dark-field microscopy positive, syphilis serology, and patient history.