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Procedures for In Vitro Cultivation of Treponema pallidum, the Syphilis Spirochete
Published on: January 24, 2025
Azithromycin resistance in Treponema pallidum
Kenneth A Katz1, Jeffrey D Klausner
1Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Current Opinion in Infectious Diseases
|January 15, 2008
Summary
Azithromycin resistance in Treponema pallidum is increasing, leading to syphilis treatment failures. This necessitates enhanced surveillance and development of new antibiotics to combat emerging drug resistance.
Area of Science:
- Microbiology
- Infectious Diseases
- Public Health
Background:
- Penicillin is the recommended syphilis treatment, but azithromycin is used as an alternative.
- Emerging resistance in Treponema pallidum (T. pallidum) to azithromycin poses a significant challenge.
Purpose of the Study:
- To discuss azithromycin-related treatment failures and resistance in T. pallidum.
- To propose strategies for addressing the clinical and public health implications of this resistance.
Main Methods:
- Review of documented cases and genetic analysis of azithromycin resistance in T. pallidum.
- Epidemiological data analysis on the prevalence and spread of resistant strains.
Main Results:
- Azithromycin treatment failures in syphilis were first observed in 2002, linked to an A2058G mutation in the 23S rRNA gene of T. pallidum.
- This mutation confers resistance by preventing azithromycin binding to the bacterial 50S ribosomal subunit.
- Azithromycin resistance has been detected in the US, Ireland, and Canada, with increasing prevalence over time. Prior macrolide use is a risk factor.
Conclusions:
- T. pallidum remains sensitive to penicillin, but azithromycin resistance is a growing concern in North America and Europe.
- The rise in azithromycin resistance presents clinical and public health challenges, highlighting the need for antibiotic development and resistance surveillance.
- Clinicians and public health officials must remain vigilant for treatment failures when azithromycin is used for syphilis.
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