Efficacy of Doxycycline-Sitafloxacin Sequential Therapy for Urogenital Mycoplasma genitalium Infection in Nanjing, China.

Background: The aim of this study was to evaluate the efficacy of doxycycline-sitafloxacin sequential therapy in the treatment of Mycoplasma genitalium (Mg) urogenital infections in Nanjing, China.

Methods: Potential subjects were tested initially for Mg infection by nucleic acid amplification testing and again at least 21 days after completion of doxycycline (100 mg twice daily for 7 days)-sitafloxacin (100 mg twice daily for 7 days) sequential therapy. The presence of macrolide and quinolone resistance-associated mutations in 23S rRNA, parC, gyrA, and gyrB genes in Mg was examined at baseline and upon retesting of specimens from subjects that did not clear Mg.

Results: A total of 218 patients were screened for Mg, of whom 65 were positive for Mg; 63 Mg-infected patients were enrolled. Twenty-two (35%) Mg-infected subjects (16 heterosexual men, 5 women, and 1 man who had sex with men [MSM]) were successfully evaluated with a test of cure; 20 (91%) cleared Mg infection. In pretreatment specimens, mutations in 23S rRNA, parC (G248T [S83I]), gyrA (G277T [G93C]), and gyrB genes were present in 100% (19 of 19), 61.1% (11 of 18), 6.7% (1 of 15), and 7.1% (1 of 14), respectively. Mg clearance rates were 4 of 4 in infected subjects that possessed both wild-type parC and gyrA genes, and 9 of 10 when a parC G248T mutation and an otherwise wild-type gyrA gene were identified. Two subjects (9%) reported mild adverse events.

Conclusions: Doxycycline-sitafloxacin sequential therapy was well tolerated and effective against most urogenital Mg infections in Nanjing and may provide an option for treatment.