The prevalence of bacterial sexually transmitted infections (STIs) such as Chlamydia trachomatis, Neisseria gonorrhoea and syphilis has been increasing globally1,2,3 .Clinically the presumptive antibiotic treatment of these bacterial STIs in symptomatic patients and their contacts is advocated to reduce morbidity and transmission risk4. But there has been an emergence self-prescribed antibiotic usages as pre- and post-exposure by individuals in the community5 However, presumptive, and prophylactic use of antibiotics and antimicrobials is not without risk. Worldwide the prevalence of anti-microbial resistance has been increasing and it has been declared ‘one of the biggest threats to global health, food security, and development today6
In this episode, we will review good practice and recent research as well as the community perspective on presumptive and prophylactic STI treatment.
Join Dr. Manoji Gunathilake, Assistant Professor, Dr. Will Nutland and Dr. Fabiola Martin in this episode of STI podcast!
Facts and highlights
A. Presumptive antimicrobial treatment
- Although clinical STI guidelines vary locally, presumptive antimicrobial treatment of bacterial STIs for patients with significant signs and symptoms and their sexual contacts, while confirmatory results are pending, are commonly prescribed.
- This practice prevents morbidity and transmission risk significantly.
- While presumptive treatment treats symptoms, not all diagnoses are confirmed through a laboratory test, potentially contributing to antimicrobial resistance.
- Always obtain Neisseria gonorrhoea prior to presumptive treatment.
- Never treat screen or presumptively treat Mycoplasma genitalium, since there is a high prevalence of 1st and 2nd line antibiotic resistance.
B. Prophylactic antimicrobial treatment
- Prophylactic STI treatment may be increased in key-populations.
- Results from a community survey given to current users of HIVPrEP showed that approximately 1:10 of the 1856 participants had used self-prescribed STI antibiotic prophylaxis5. People preferred post-exposure prophylaxis over pre-exposure treatment, limiting pill burden.
- However around 1:4 people were estimated to be self-prescribing ineffective antibiotics5, potentially contributing to antimicrobial resistance.
- Clinicians need to positively encourage their patients to disclose PEP/PrEP antibiotic usage to manage STIs effectively and to limit exposure to antimicrobial resistance.
- Real-world efficacy data on STI prophylaxis is promising.
- A randomised, open-label clinical trial, highly sexually active participants were randomised to take 200 mg of doxycycline within 72h after sex and or to be in the control arm. The trial had to be terminated prematurely due to the significant reduction in bacterial STI incidence in the intervention vs control arm (10.3% vs 29%). An increased antibiotic resistance was not detected7.
- Please listen to our bonus podcast with the principal investigators of this trial: Prof Annie Luetkemeyer and Prof Connie Celum on BMJ STI Podcasts.
References and Additional Resources
1) Sexually transmitted infections and screening for chlamydia in England, 2020
3) Sexually transmitted infections in England, 2020
6) WHO fact-sheet on antimicrobial resistance
Additional
Doxycycline PEP significantly reduces STIs in people at high risk of infections
Taking antibiotic after sex cuts STIs by two-thirds, ‘DoxyPEP’ study finds
Doxycycline post-exposure prophylaxis for STI prevention among MSM and transgender women on HIV PrEP or living with HIV: high efficacy to reduce incident STI’s in a randomized trial – https://programme.aids2022.org/Abstract/Abstract/?abstractid=13231