Antimicrobial Susceptibility of Neisseria gonorrhoeae in Japan from 2000 to 2015.
Gonococcal infections are difficult to treat because of their multidrug antimicrobial resistance. The outbreak of antimicrobial-resistant Neisseria gonorrhoeae has begun in Asia and particularly in Japan. Therefore, it is very important that we understand the trend of antimicrobial resistance of N. gonorrhoeae in Asia including Japan. Our surveillance of the antimicrobial susceptibility of N. gonorrhoeae began in 2000 under the guidance of the Department of Urology, Gifu University. We report our surveillance data from 2000 to 2015.



We collected N. gonorrhoeae strains isolated from patients with gonococcal infections who visited our cooperating medical institutions in Japan from 2000 to 2015. MICs of penicillin G, cefixime, ceftriaxone, tetracycline, spectinomycin, azithromycin, and levofloxacin were determined by the agar dilution method approved by the Clinical and Laboratory Standards Institute.



From 2000 to 2015, 2471 isolates of N. gonorrhoeae were collected in Japan. High rates of nonsusceptibility to penicillin, tetracycline, levofloxacin, cefixime, and azithromycin were shown. Around 5% to 10% of the strains isolated had a 0.25-mg/L MIC of ceftriaxone in each year, and 6 strains (0.24%) with a 0.5-mg/L MIC of ceftriaxone were isolated throughout the study period. Approximately 5% to 10% of the strains were resistant to each of ceftriaxone, azithromycin, and levofloxacin according to European Committee on Antimicrobial Susceptibility Testing breakpoints, and the rate has not increased significantly.



From this study and previous pharmacodynamic analyses, a single 1-g dose of ceftriaxone is recommended to treat gonorrhea. As strains with high-level ceftriaxone resistance continue to spread, higher doses of ceftriaxone in monotherapy or multiple doses of ceftriaxone should be considered.
From the *Department of Urology, Gifu University Hospital; †Antimicrobial Susceptibility Surveillance of Neisseria gonorrhoeae; ‡Department of Urology, Graduate School of Medicine, Gifu University, Gifu; §iClinic; ¶Kitanohara Women's Clinic, Miyagi; ∥Yoh Urology and Dermatology Clinic; **Nagoya Urology Hospital; ††Narita Clinic, Aichi; ‡‡Kido Clinic; §§Department of Urology, Irumagawa Hospital, Saitama, Japan.
Mitsuru
M
Yasuda
Kyoko
K
Hatazaki
Shin
S
Ito
Masataka
M
Kitanohara
Mutsumasa
M
Yoh
Munekado
M
Kojima
Harunori
H
Narita
Akira
A
Kido
Kazutoyo
K
Miyata
Takashi
T
Deguch
D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial / Q000187:drug effects*; D006069:Gonorrhea / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D009344:Neisseria gonorrhoeae / Q000187:drug effects* / Q000302:isolation & purification; D011159:Population Surveillance
D000900:Anti-Bacterial Agents