General principles:
- Contact tracing either via patient or through sexual health clinic, up to last 6 months
- Consider treating partners even if asymptomatic (depending on condition)
- No sexual contact until treatment complete
- Usually follow up testing to confirm eradication
- Screen for other concurrent STIs – eg if presents with warts, consider screening for rest
Aust guideline for asymptomatic screening:
- Those who request it, increased risk (new sexual partner or overseas risk), known exposure or history, MSM every 3 months.
- RACGP guidelines recommend opportunistic screening for young people who are sexually active
Chlamydia
- Very common esp in < 30 year olds – most commonly detected notifiable condition in Aust – detected in 1 in 20 young screening tests in Aust.
- Caused by chlamydia trachomatis
- 85 – 90 % asymptomatic.
- May present with dysuria, discharge, pain, epididymo-orchitis, or PID.
- Test = first pass urine NAAT, endocervical swab in women, anorectal swab in MSM.
- Test concurrently for gonorrhoea.
- Treatment = 100 mg doxycycline BD for 7 days, or 1 g azithromycin stat.
- Contact tracing back 6 months.
- Guidelines suggest testing for cure is not necessary – if doing so, wait 4 weeks. But re-infection is very common, so consider re-testing at 3 months.
Gonorrhoea
- Most commonly diagnosed in MSM, ATSI (esp remote communities) and returned travellers. Increasing prevalence especially in young women, and emerging resistance to first line treatment.
- Caused by Neisseria gonorrhoea.
- Vaginal gonorrhoea is often asymptomatic (80 %), whilst penile urethral gonorrhoea is almost always symptomatic (85 – 90 %).
- May present with penile discharge, dysuria, vaginal discharge, dyspareunia, conjunctivitis, epididymo-orchitis or PID.
- Testing before treatment is important due to emerging resistance.
- Test = first pass urine NAAT, penile urethral swab if discharge. Anal and pharyngeal swab for MSM.
- Treatment = 500 mg ceftriaxone IM/IV stat PLUS 1 g azithromycin stat.
- Contact trace as normal.
- Should be re-tested for cure at 2 weeks. Re-infection is common.
Syphilis
- Highest prevalence in MSM and ATSI communities. Increasing prevalence in general population.
- Caused by treponema pallidum.
- 50 % asymptomatic and diagnosed with screening serology.
- Primary syphilis – defined by painless ulcer (chancre) with well defined margin and firm base. Occasionally multiple or painful. Incubation period 10 – 90 days, avg 3 weeks. Often heals spontaneously. Inguinal lymphadenopathy common. Highly infectious.
- Secondary syphilis – > 6 weeks after infection with systemic signs and symptoms. Constitutional symptoms, rash & condylomata lata. Still highly infectious and symptoms may resolve or recur.
- Early latent syphilis – asymptomatic but with positive serology and acquired within 2 years – potentially still highly infectious.
- Late latent syphilis – > 2 years since acquisition, asymptomatic, usually not sexually infectious but may still have vertical transmission.
- Tertiary syphilis – late symptoms including destructive skin lesions (gummas), cardiovascular or neurological disease.
- Test = t. pallidum antibody serology +/- swab of the base of ulcer if present. Check serology in anyone with another STI, unknown genital ulcers.
- Treatment = IM benzylpenicillin, under ID guidance +/- syphilis registry.
- Jarisch-Herxheimer reaction – common reaction in patients undergoing treatment for primary and secondary syphilis – 6-12 hours after commencing treatment, reaction of constitutional symptoms (fever, headache, malaise, arthralgia) lasting for hours. Manage conservatively.
Genital herpes
- Highly stigmatised and poorly understood.
- Most HSV is asymptomatic or mild and diagnosis not sought. When symptoms appear, it can be anytime including years after being acquired. Very prevalent (70 – 80% HSV1, 12 – 15% HSV2)
- Caused by herpes simplex virus 1 and 2.
- Primary episodes associated with ulceration and systemic viral infection.
- Usually presents with ulcerations, but also genital fissures, erythema and itching, cervix inflammation, psychosexual stress, urethritis, or rarely extra-genital involvement.
- Diagnosis is by swabs at base of ulcer or deroofed vesicle.
- Management is valaciclovir 500 mg BD for 5 – 10 days for initial episode, then for 3 days at the initiation of recurrent symptoms. (alternative is acyclovir)
- Topical lignocaine can help. Contact tracing “not recommended”.
- Can try daily valaciclovir for 6 months for suppressive therapy.
- Dangerous during third trimester or delivery – suppressive therapy during last month of pregnancy.
Mycoplasma genitalium
- Often asymptomatic but established cause of dysuria, urethritis, PID, epididymo-orchitis.
- Diagnosis by first pass urine.
- Testing for macrolide (azithromycin) resistance is recommended – can be 60 – 80 %.
- Treatment is doxycycline 100 mg BD for 7 days and azithromycin 1 g stat then 500 mg BD for 3 days.
- If macrolide resistant – doxycycline 100 mg BD for 7 days, followed by moxifloxacin 400 mg daily for 7 days.
- No sex without condoms until test of cure at 14 – 21 days. Contact tracing needed.
Trichomoniasis
- More common in older people.
- Caused by trichomonas vaginalis (protozoa) which infects vagina, urethra and paraurethral glands.
- Often asymptomatic in men – may present with dysuria, urethritis, prostatitis or as discharge in women.
- Diagnosis by vaginal swab or first pass urine.
- Treat with metronidazole 400 mg BD for 7 days.
Donovanosis (granuloma inguinale)
- Very rare cause of genital ulceration – consider in returned travellers (PNG etc).
- Caused by Klebsiella granulomatis.
- Diagnosis by dry swab or punch biopsy (specific labs)
- Treat with azithromycin or doxycycline.
Differential diagnosis of a genital ulcer:
STI | Other |
Herpes simplex virus
Syphillis Donovanosis (rare) Lymphogranuloma venereum (rare) |
Fixed drug eruption
Aphthous ulcer Trauma PeIN or cancer Behcet disease Crohn’s disease |
General principles:
- Contact tracing either via patient or through sexual health clinic, up to last 6 months
- Consider treating partners even if asymptomatic (depending on condition)
- No sexual contact until treatment complete
- Usually follow up testing to confirm eradication
- Screen for other concurrent STIs – eg if presents with warts, consider screening for rest
Aust guideline for asymptomatic screening:
- Those who request it, increased risk (new sexual partner or overseas risk), known exposure or history, MSM every 3 months.
- RACGP guidelines recommend opportunistic screening for young people who are sexually active