Gonorrhoea is the second most common bacterial STI in the UK. The main risk groups include men who have sex with men (MSM), who account for 30 per cent of diagnoses in men, and black ethnic populations.
The causative bacterium, Neisseria gonorrhoeae, is spread by direct inoculation of secretions from one mucous membrane to another. It infects the mucosal surfaces of the genital tract, including the urethra in both men and women, the genital glands (such as Bartholin's), the cervix, fallopian tubes and epididymides. It can also infect the anal canal and distal rectum, the oropharynx and the eye.
1. Clinical features
The symptoms and signs of gonorrhoea depend on the site of infection, which will depend upon sexual contact.
Most men with urethral infection usually develop symptoms (most commonly discharge or discharge with dysuria) three to 10 days after exposure.
Cervical infection in women is asymptomatic in about 70 per cent of cases. The symptoms that do occur (vaginal discharge, low abdominal or pelvic pain) are non-specific.
Rectal infection may cause rectal/anal pain or discharge, but is often asymptomatic. In women, rectal infection can occur in the absence of anal intercourse. Pharyngeal infection is usually asymptomatic.
Examination may be normal. In men, the most common finding is urethral discharge, which varies from mucoid to purulent. In women, the most common signs are mucopurulent cervicitis and vaginal discharge, which is often caused by concomitant pathogens. The discharge of gonorrhoea has no pathognomonic features.
Complications of gonorrhoea are seen when infection remains untreated for a prolonged period. In the UK, the most common local complications are salpingitis and epididymitis. Disseminated infection is rare. Complications occur in about 3 per cent of cases in females and in less than 1 per cent in males.
The diagnosis is established by the identification of N gonorrhoeae. The tests available vary and will be influenced by the local prevalence of gonorrhoea.
Culture offers a specific and cheap test that allows diagnosis and provides information on antimicrobial sensitivities. Nucleic acid amplification tests (NAATs) have high specificity and sensitivity, and enable non-invasive sampling. However, they are expensive, lack the advantage of enabling antibiotic sensitivity testing and there are some false positive results.
Confirmation of a NAAT- positive result by culture is advisable. Currently no NAATs are licensed for use with rectal or pharyngeal samples.
3. Specimen collection
In men, specimen collection is routinely from the urethra and, in MSM, rectal samples should be obtained if there is history of oroanal or anogenital contact, ideally using a proctoscope. The oropharynx should be sampled in all gonorrhoea contacts. A first-pass urine provides an alternative urethral specimen for testing with a NAAT.
In women, specimen collection is routinely from the endocervix and the urethra; perform rectal and oropharyngeal tests when symptomatic at these sites, when a sexual partner has gonorrhoea and when indicated by sexual history.
A self-taken vaginal swab has good sensitivity and is an alternative to screening tests using a NAAT.
In recent years, gonococcal antibiotic resistance has increased and providing effective therapy is becoming a challenge. In some countries, gonococcus no longer responds reliably to available antibiotics.
In the UK in 2008, 24 per cent of gonorrhoea cases had penicillin resistance, 60 per cent had tetracycline resistance, 28 per cent had quinolone resistance and 4.1 per cent had azithromycin resistance.
Referral to your local GUM clinic is strongly advised. However, if this is difficult to arrange, the recommended first-line treatments for uncomplicated infections are IM ceftriaxone 250 mg or oral cefixime 400 mg.
In men and women with ascending local infection (epididymo-orchitis, salpingitis), standard therapy should be supplemented with a two-week course of an antichlamydial antibiotic.
In pelvic infection, metronidazole is commonly added because anaerobic organisms often coexist with N gonorrhoeae.
Sexual abstinence should be advised until eradication is confirmed and sexual partners have been screened and treated.
5. Coexistent STIs
Testing for coexistent STIs is important in all patients with gonorrhoea. Chlamydial infection is particularly common in both men and women (approximately 30 per cent) and concurrent treatment for chlamydia should be considered, especially if the patient is unlikely to attend for follow up.
6. Follow up
Patients should be assessed after treatment to confirm resolution of symptoms and partner notification. A test of cure should be undertaken if the patient has pharyngeal infection, is symptomatic after treatment, has received a suboptimal treatment, a resistant strain is identified or there is a possibility of re-infection. If a test of cure is performed, culture tests should be performed at least 72 hours after completion of all antibiotic therapy and NAATs two weeks after the end of antibiotics.
7. Contact tracing
It is essential that all recent sexual partners are tested for gonorrhoea and coexisting STIs. Male patients with symptomatic urethral infection should notify all sexual partners in the preceding two weeks or their last partner if longer ago.
Asymptomatic patients and those with infection at other sites should notify all sexual partners in the three months before diagnosis, or the previous partner if it is longer since the last change of partner.
In neonates diagnosed with gonococcal ophthalmitis, it is important that the mother and her sexual partners are managed as gonococcal contacts.
- Dr Sherrard is a consultant GUM physician at Oxford Radcliffe NHS Trust
- British Association for Sexual Health and HIV. UK management guidelines. www.bashh.org
- GRASP Steering Group. The Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) Year 2008 report. London: Health Protection Agency 2009. www.hpa.org.uk