Early syphilis: serological treatment response to doxycycline/tetracycline versus benzathine penicillin

Abstract

Introduction: Benzathine penicillin G is the treatment of choice for syphilis, but doxycycline and tetracycline are effective second-line treatments. The objective of this study was to assess the serological response to treatment for early syphilis with benzathine penicillin compared with doxycycline or tetracycline. Methodology: We examined rapid plasma regain (RPR) serological test results of all first-time early syphilis patients in Peking Union Medical College Hospital between 2000 and 2011, comparing treatment with two doses of penicillin to 14-day course of oral doxycycline (100 mg twice daily) or oral tetracycline (500 mg 4 times a day). Results: Of the 641 early syphilis cases with available treatment outcome data, 606 (94.5%) received penicillin and 35 (5.5%) received doxycycline/tetracycline. More than half (52.1%) had secondary syphilis, 13.4% had primary syphilis, and 34.5% had early latent syphilis. A statistically similar serological treatment success rate (p = 0.157) was observed in penicillin-treated patients 91.4% (554/606), when compared with patients treated with doxycycline/tetracycline 82.9% (29/35). Conclusion: Doxycycline/tetracycline had a similar serological treatment success rate when compared to penicillin in the treatment of early syphilis.