TABLE 3.
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 result | No. of cases with the following clinical diagnosis at STI clinicb: |
|
|---|---|---|
| + | − | |
| + | 83 | 10 |
| − | 31 | 592 |
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.