
Methods: Between September 2009 and April 2013, a surveillance study for macrolide-resistant T. pallidum was conducted in eight designated hospitals for HIV care around Taiwan, in which clinical specimens were prospectively collected from patients who presented with syphilis. By following the typing system proposed by Marra and colleagues for T. pallidum isolates, we examined the number of 60-bp repeats in the acidic repeat protein (arp) gene, T. pallidum repeat (tpr) polymorphism, and tp0548 gene. Detection of A2058G point mutation of 23S rRNA of T. pallidumwas performed using restriction fragment length polymorphism (RFLP).
Results: During the study period, we collected 567 clinical specimens from 373 patients with syphilis. T. pallidum DNA was identified from 46.7% (n=265) of the specimens that were collected from 207 patients (55.5%). 184 patients (88.9%) had clinical specimens that were tested positive for 23S rRNA and examined for macrolide resistance. Only one isolate (0.5%) had A2058G mutation on 23S rRNA, which was isolated from an HIV-infected individual who reported that he likely acquired syphilis while having unprotected sex in Hong Kong in January 2013. Ninety-two of the 265 isolates (34.7%) were completely typeable. Type 14f/f (n=52 isolates) was the most common isolates, followed by 14b/c (11), 14k/f (5), 14a/f (4), and others (6f/f, 9f/f, 10b/a, 13b/c, 14j/f, 14j/c, 14k/c, 14f/a, 14e/f, 14b/f, 14f/c, and 15k/c).
Conclusion: We found that type 14f/f was the most common T. pallidum strain in this multicenter study on syphilis in Taiwan and the prevalence of T. pallidum that exhibited A2058G mutation on 23S rRNA remains low in Taiwan.

S. Y. Chang,
None
W. C. Liu, None
Y. C. Su, None
S. P. Yang, None
P. Y. Wu, None
C. C. Hung, None