Chlamydia
Overview
- The most commonly reported communicable disease in Australia
- Those <30 years are at greatest risk
- Frequently asymptomatic
- Simple to test and treat
- Immunity to new infection is not provided by previous infection.
Cause
Chlamydia trachomatis (See also Lymphogranuloma venereum).
Clinical presentation
| Male | Female |
| Symptoms | |
|
50% have no symptoms |
75% have no symptoms |
|
Dysuria |
|
|
Urethral discharge |
|
|
Testicular pain |
|
|
Intermenstrual bleeding |
|
|
|
Postcoital bleeding |
|
Ano-rectal symptoms |
|
| Complications | |
| Epididymo-orchitis | Pelvic inflammatory disease (PID) |
| Reactive arthritis: arthralgia, hypertrophic rash on soles, circinate balanitis, psoriatic rash | Infertility |
| Ectopic pregnancy | |
| Reactive arthritis: arthralgia, hypertrophic rash on soles, psoriatic rash | |
See STI Atlas for images.
Special considerations
May also infect the eye, anus and rarely throat.Diagnosis
| Diagnosis in males | ||
|---|---|---|
| Test | Site/Specimen | Consideration |
| NAAT | First Pass Urine (FPU) |
If MSM also collect anal and pharyngeal swab even if asymptomatic at these sites. |
| NAAT | Ano-rectal swab | If MSM, and patient declines anal examination or has no ano-rectal symptoms, instruct in Self-collection of samples for NAAT testingVaginal swab: instruct the patient to insert the swab into the vagina like a tampon and then remove and place into the transport tube. Rectal swab: instruct the patient to insert the swab into the anal canal 2-4cms and then remove and place into the transport tube. FPU (First pass urine): Collect approximately 20 ml (1/3 of the standard urine jar) of the first part of the urine stream in a specimen jar at the time you are consulting the patient. The patient does not need to have held their urine for more than 20 minutes prior to specimen collection. A midstream urine (MSU) or early morning specimen (i.e. first void urine) are not required for NAAT. Click here for information on how to describe self-collection technique to a patient. If ano-rectal symptoms present, collect via proctoscope, or encourage Self-collection of samples for NAAT testingVaginal swab: instruct the patient to insert the swab into the vagina like a tampon and then remove and place into the transport tube. Rectal swab: instruct the patient to insert the swab into the anal canal 2-4cms and then remove and place into the transport tube. FPU (First pass urine): Collect approximately 20 ml (1/3 of the standard urine jar) of the first part of the urine stream in a specimen jar at the time you are consulting the patient. The patient does not need to have held their urine for more than 20 minutes prior to specimen collection. A midstream urine (MSU) or early morning specimen (i.e. first void urine) are not required for NAAT. Click here for information on how to describe self-collection technique to a patient. |
| NAAT | Pharyngeal swab | Collect if MSM. |
| NAAT – Nucleic Acid Amplification Test FPU – First pass urine MSM – Men who have sex with men |
||
| Diagnosis in females | ||
|---|---|---|
| Test | Site/Specimen | Consideration |
| NAAT | Endocervical swab | Best test if examined |
| NAAT | Self-collected vaginal swab | If not examined |
| NAAT | FPU | Only if endocervical swab/self-collected vaginal swab cannot be taken e.g. after a hysterectomy. Not as sensitive as self-collected vaginal swab. |
| NAAT | Ano-rectal swab | If patient has had anal sex or has ano-rectal symptoms. If patient declines anal examination, instruct Self-collection of samples for NAAT testingVaginal swab: instruct the patient to insert the swab into the vagina like a tampon and then remove and place into the transport tube. Rectal swab: instruct the patient to insert the swab into the anal canal 2-4cms and then remove and place into the transport tube. FPU (First pass urine): Collect approximately 20 ml (1/3 of the standard urine jar) of the first part of the urine stream in a specimen jar at the time you are consulting the patient. The patient does not need to have held their urine for more than 20 minutes prior to specimen collection. A midstream urine (MSU) or early morning specimen (i.e. first void urine) are not required for NAAT. Click here for information on how to describe self-collection technique to a patient. |
| NAAT – Nucleic Acid Amplification Test FPU – First pass urine |
||
Specimen collection
Urethral swabs for microscopy should be collected when the patient has not urinated for at least 1 hour and only if the patient has frank urethral discharge. Squeeze the urethra to express the discharge and collect on urethral swab. It is not necessary to insert the swab into the urethra. Vaginal swab: instruct the patient to insert the swab into the vagina like a tampon and then remove and place into the transport tube. Rectal swab: instruct the patient to insert the swab into the anal canal 2-4cms and then remove and place into the transport tube. FPU (First pass urine): Collect approximately 20 ml (1/3 of the standard urine jar) of the first part of the urine stream in a specimen jar at the time you are consulting the patient. The patient does not need to have held their urine for more than 20 minutes prior to specimen collection. A midstream urine (MSU) or early morning specimen (i.e. first void urine) are not required for NAAT. Click here for information on how to describe self-collection technique to a patient.Clinician collected for NAAT/culture/microscopy
Rectal swabs should be collected by inserting a sterile swab 2-4cms into the anal canal and moving the swab gently side to side for 10-20 seconds.
Pharyngeal swabs should be collected from the tonsils and oropharynx.
High vaginal swab of vaginal discharge smeared onto a glass slide, air dried and sent for microscopy. Swab inserted into transport medium for culture.Self-collection of samples for NAAT testing
Asymptomatic patients can collect most samples themselves, including vaginal swabs and ano-rectal swabs.
Investigations
- NAATs are highly sensitive, and can be used in non clinical and non urban settings. They are the only easily accessible tests for chlamydia.
- Encourage patient self-collection of vaginal swabs, urine and ano-rectal swabs.
- Gonorrhoea can and should be tested for on the same NAAT specimens.
Clinical indicators for testing
Test for chlamydia in the following situations:
- <30 years and sexually active
- partner change in the last 12 months
- have had an STI in past 12 months
- have had a sexual partner with an STI
- at increased risk of complications of an STI e.g. termination of pregnancy (TOP) or intrauterine device (IUD) insertion
- signs or symptoms suggestive of chlamydia
- patient requests a sexual health check.
Management
| Principal Treatment Options | ||
|---|---|---|
| Situation | Recommended | Alternative |
| Uncomplicated genital or pharyngeal infection |
Doxycycline 100mg PO, BD 7 days |
|
| Ano-rectal infection |
Doxycycline 100mg PO, BD 7 days if asymptomatic, but 21 days if symptomatic (see ano-rectal syndromes) |
Azithromycin 1g PO, stat, and repeat in 1 week |
Treatment advice
- Treat immediately if high index of suspicion. If urethritis symptoms use Doxycycline while awaiting test results (See NSU) or if contact of index case use either Azithromycin or Doxycycline depending on assessment of adherence or patient preference
- Start treatment for patient and sexual partner(s) without waiting for lab results.
- Use azithromycin as the principle treatment option when nursing administered standing orders available.
- If a patient has an intrauterine device (IUD), leave IUD in place and treat as recommended. Seek specialist advice as needed.
- If symptomatic anorectal infection, ensure lymphogranuloma venereum (LGV) testing is requested.
Other immediate management
- Advise no sexual contact for 7 days after treatment is administered.
- Advise no sex with partners from the last 6 months until the partners have been tested and treated if necessary.
- Contact tracing.
- Provide patient with factsheet.
- Notify the state/territory health department.
Special treatment situations
Special considerations
- Consider seeking specialist advice before treating any complicated presentation.
| Situation | Recommended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pregnant women
For more information go to the Therapeutic Goods Association's Prescribing medicines in pregnancy database and/or seek specialist advice.  |
Azithromycin 1g PO, stat | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Allergy to principal treatment choice |
If both principle treatment options unsuitable, seek specialist advice. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Rectal coinfection |
For rectal coinfection with gonorrhoea, treatment should be given for both infections i.e.: |
Contact tracing
- Contact tracing is important to prevent reinfection and reduce transmission
- Male and female partners should be traced back for 6 months
- Offer recommended treatment to all sexual contacts
- Consider the use of patient delivered partner therapy (PDPT), where appropriate. PDPT is currently legal in VIC and NT.
See Australasian Contract Tracing Manual - Chlamydia for more information.
Follow up
Review in 1 week provides an opportunity to:
- Confirm patient adherence with treatment and assess for symptom resolution.
- Confirm contact tracing procedures have been undertaken or offer more contact tracing support.
- Provide further sexual health education and prevention counselling.
Test of Cure (TOC)
Not routinely recommended, unless in the following groups:
- Pregnant women
- Rectal chlamydia
TOC by Nucleic Acid Amplification Test (NAAT) in these situations should be performed at least 4 weeks after treatment is completed. An earlier TOC could yield a false positive result due to the presence of chlamydia DNA remnants.
Retesting
- Re-infection is common
- Re-testing at 3 months is recommended, to detect re-infection.
Consider testing for other STIs, if not undertaken at first presentation, or retesting post the window period.
Auditable outcomes
- 100% of patients diagnosed with chlamydia are treated with an appropriate antibiotic regimen
- 100% of patients are advised to avoid sexual contact for 7 days after treatment is administered
- 50% of patients are retested at 3 months.