Sexually transmitted infections
Sexually transmitted infections (STIs) are frequently seen in general practice. Although they may be asymptomatic, they are important to detect early in order to minimise potential complications such as infertility.
Taking a sexual history
A key skill involved in the assessment and management of STIs is taking a sexual history. This should start with providing a nonjudgmental, supportive environment in which patients feel comfortable to discuss sexual matters.180 It is important to ask open questions and to avoid terms that make assumptions about sexual behaviour or orientation (eg. by using the term ‘partner’). The history should address issues such as current sexual activity, gender and number of partners, contraception (including use of condoms), immunisation status and other risk factors for blood borne viruses (eg. injecting drug use, tattooing and piercing). Any investigations should be explained and patients should be counselled before ordering tests such as those for HIV or hepatitis C.
A follow up appointment may be suggested with the partner and explicit permission is required for the GP to undertake follow up with contacts. (See contact tracing manual at www.ashm.org. au/contact-tracing/.)
In the case of a notifiable condition, the patient should be informed that case notification to public health authorities will occur. Notification should be made as prescribed by the department of health in your state or territory.
The individual’s age, sexual behaviour and community STI prevalence influence the level of risk. The GP should use this information to guide their recommendations for STI screening.
6.2.1 Chlamydia
| Age | 0 - 9 | 10 - 14 | 15 - 19 | 20 - 24 | 25 - 29 | 30 - 34 | 35 - 39 | 40 - 44 | 45 - 49 | 50 - 54 | 55 - 59 | 60 - 64 | 65 - 69 | 70 - 79 | >80 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| X | X | 27 |
Screening for Chlamydia trachomatis infection in all sexually active females under 25 years of age is recommended (because of their risk of complications), as well as possible screening for other STIs if indicated by risk assessment. There is a lack of evidence that screening and treatment of all males results in reduced population prevalence. Other STIs to consider screening high risk individuals for include gonorrhoea, HIV and syphilis.177 The risk for gonorrhoea, HIV and syphilis is low for heterosexuals in all major cities in Australia and New Zealand.178 The individual’s age, sexual behaviour and community STI prevalence influence the level of risk. This information should be used to guide what infections to test for.
Men who have sex with other men should be screened for gonorrhoea, chlamydia, syphilis and HIV every 12 months. A significant proportion of men with STIs have no symptoms.179 Screening for HCV should be provided if HIV positive or has a history of injecting drug use.
There is good evidence to suggest all pregnant women at risk should be screened for hepatitis B, HIV, and syphilis;177 and chlamydia and gonorrhea if considered to be at risk.181
| Who is at higher risk of infection and complications? | What infections/actions should be considered? | How often? | Level of evidence and references |
|---|---|---|---|
High risk
|
|
|
II A 182-186 |
| High risk men Men who have sex with other men |
|
At least every 12 months |
III B 179,187,188 |
|
|||
| Sexual partners of infected women and men | Test and then treat. Post-treatment test of cure is not recommended. Repeat testing of women to check for re-infection after 3–12 months may be appropriate | Test and treat all contacts. If retesting is indicated leave a minimal interval of 6 weeks posttreatment | II A 189-191 |
| Asymptomatic requesting ‘STI check up’ | Urine or genital swab for chlamydia, serology for hepatitis B, syphilis, HIV | III B 188 | |
| * This does not require patients to be recalled | |||
| Test | Technique | Site | Level of evidence and references |
|---|---|---|---|
| Nucleic acid amplification test (NAAT) most commonly by PCR | Should be (20 mL) first void urine (not mid stream) at least 1 hour after last
void. This has been found to be the best performing chlamydia test in both
genders. Urine samples should be kept at under 4°C.
PCR endocervical or vaginal swab (patient can self collect) also possible in females (there has been no validation of this technique for anal or throat swabs) |
Urine, endo-cervix, vagina | I B 178,187 190,192 |
| V 188 | |||
| Gonorrhoea MCS | Rectal swab should be inserted 3 cm into anus and rotated | 193 |
Implementation
Chlamydia infection is the most common, curable STI in Australia. Notification rates per 100 000 have increased from 35.4 in 1993 to 217 in 2005. Most cases are in the 15–39 years of age group (particularly in the 20–29 years group). Infection rates in Australia vary from 4–12%. Young people and Aboriginal people and Torres Strait Islanders have the highest infection rates; 12–34% in some locations. There is an increased risk of gonorrhoea, syphilis, and trichomoniasis among Aboriginal people and Torres Strait Islanders.
Screening of sexually active women under 25 years of age for chlamydia on an annual basis has been shown to half the infection and complication rates.194,195 Male partners of infected females should be tested and treated. A USA study found that providing treatment for the heterosexual partners of those infected reduced the re-infection rate more than contact tracing (II A).196
Untreated pregnant women infected with chlamydia have a 20–50% chance of infecting their infant at delivery.197
© The Royal Australian College of General Practitioners
Printed from www.racgp.org.au/redbook