Gonorrhoea

01OverviewDefinition, clinical context and the essential points that orientate the chapter.

Neisseria gonorrhoeae infects the urethra, endocervix, rectum, pharynx and conjunctiva. Urethral infection often produces purulent discharge and dysuria, while cervical, rectal and pharyngeal infection is frequently silent. Symptoms cannot determine the infected sites, and a genital diagnosis does not clear the throat or rectum. The 2025 BASHH guideline therefore strengthens anatomical sampling and specifically recommends pharyngeal testing for all people with urogenital gonorrhoea and all contacts.

NAAT provides sensitive detection, but culture remains indispensable because viable isolates permit antimicrobial susceptibility testing and surveillance. Obtain culture from every clinically suspected or NAAT-positive site before treatment when feasible. Microscopy can rapidly demonstrate intracellular Gram-negative diplococci in symptomatic penile urethritis, but sensitivity is lower at cervical and asymptomatic sites. A negative smear therefore cannot rule out infection, and culture or NAAT from one site says nothing about unsampled anatomy.

Ceftriaxone 1 g intramuscularly once is recommended for uncomplicated anogenital and pharyngeal infection when susceptibility is unknown. Gonococcal resistance makes empirical oral substitution unsafe. Ciprofloxacin is no longer preferred first-line treatment because resistance and serious adverse-effect concerns require demonstrated susceptibility and an individual decision. The oral cefixime alternative uses two 400 mg doses six to twelve hours apart under the current guideline, and non-standard regimens need specialist advice because pharyngeal failures are more common.

Test-of-cure decisions now depend on site, regimen, susceptibility and pregnancy. It is unnecessary after ceftriaxone 1 g for an anogenital isolate shown susceptible to ceftriaxone. It remains routine for pharyngeal infection, pregnancy, persistent signs or symptoms, unknown susceptibility, or treatment with anything other than ceftriaxone. When symptoms or signs remain, use culture at least 72 hours after treatment. When asymptomatic, use NAAT at least two weeks after treatment and culture any positive result. Interpret a positive result in clinical context as possible residual non-viable nucleic acid, reinfection or treatment failure.

Partner and public-health work are part of treatment. The lookback is two weeks, or the last partner if earlier, for symptomatic penile urethral infection; it is three months for other sites or asymptomatic infection. Contacts presenting more than fourteen days after exposure are generally treated only if positive, while earlier contacts need testing, risk assessment and sometimes repeat testing or epidemiological treatment. Abstinence continues until seven days after everyone has completed therapy. Fever, joint disease, pustules or eye disease moves care into an urgent complicated-infection pathway.

Key points

Sample every exposed anatomical site by NAAT and obtain culture from each suspected or NAAT-positive site before treatment whenever this causes no unsafe delay.
The 2025 guideline recommends pharyngeal testing for every person with urogenital gonorrhoea and every gonorrhoea contact, even without reported oral exposure.
Treat uncomplicated anogenital or pharyngeal gonorrhoea with ceftriaxone 1 g intramuscularly once when susceptibility is unknown.
Ciprofloxacin is not empirical first-line therapy; consider it only when susceptibility is demonstrated and patient-specific fluoroquinolone safety is acceptable.
Routine test of cure is not required for ceftriaxone-susceptible anogenital infection treated with ceftriaxone 1 g, but remains required for pharyngeal infection, pregnancy, persistent symptoms, unknown susceptibility or another regimen.
For symptomatic test-of-cure assessment, take culture at least 72 hours after treatment; in an asymptomatic patient use NAAT at least two weeks after treatment and culture any positive result.
Advise no sexual contact until seven days after the patient and partners have completed treatment, and document partner notification to the infection-specific lookback.
Possible ceftriaxone failure requires pre- and post-treatment isolates, urgent expert microbiology or sexual-health review, and national reporting through the applicable pathway.

02AetiologyUnderlying causes, associations and risk factors, with why each one matters.

Mucosal inoculation

N. gonorrhoeae passes in infected secretions and adheres to susceptible urethral, cervical, rectal, pharyngeal or conjunctival epithelium.

Silent reservoirs

Asymptomatic cervical and pharyngeal carriage sustains transmission and can remain undiscovered when testing is restricted to the symptomatic genital site.

Antimicrobial selection

Genetic change and horizontal resistance determinants permit rapid adaptation under antibiotic pressure, making culture surveillance central to control.

03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.

1
Epithelial attachment
Pili and outer-membrane proteins enable adherence, antigenic variation and invasion of mucosa despite local immune responses.
2
Neutrophilic inflammation
Organism products recruit neutrophils and create purulent discharge, dysuria, friable cervicitis or rectal inflammation at symptomatic sites.
3
Ascending spread
Endocervical or urethral infection can move into fallopian tubes or the epididymis, producing PID or epididymo-orchitis with fertility consequences.
4
Bloodstream dissemination
Occasional bacteraemia seeds skin, tendon sheaths and joints, causing a dermatitis-tenosynovitis syndrome or purulent septic arthritis.

04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.

Penile urethritis

Purulent urethral discharge and marked dysuria are typical, although microscopy and organism testing are still required to distinguish causes.

Cervical infection

Mucopurulent cervicitis, contact bleeding and pelvic symptoms can occur, but many endocervical infections are found through screening alone.

Extragenital disease

Rectal discomfort, discharge or proctitis and pharyngeal soreness are possible, yet both sites often carry infection without symptoms.

Disseminated syndromeRed flag

Fever, migratory arthralgia, tendon-sheath pain, sparse pustules or septic monoarthritis suggests bloodstream spread and demands admission.

Ocular emergencyRed flag

Copious purulent discharge with severe conjunctival inflammation can rapidly injure the cornea and requires urgent ophthalmological care.

Red flags requiring action

A painful swollen joint, fever, tenosynovitis or sparse pustular rash requires urgent assessment for disseminated gonococcal infection.
Hyperacute purulent conjunctivitis, eye pain, photophobia or visual change can progress to corneal perforation and needs emergency ophthalmology.
Pelvic pain with cervical motion or adnexal tenderness requires immediate broad PID treatment in addition to gonococcal coverage.
Sudden severe scrotal pain remains testicular torsion until assessed even when urethral discharge suggests infection.
Persistent symptoms or a positive post-treatment test may signal reinfection or antimicrobial failure and needs culture plus specialist resistance action. For symptomatic test-of-cure assessment, take culture at least 72 hours after treatment; in an asymptomatic patient use NAAT at least two weeks after treatment and culture any positive result.

05InvestigationsWhat to request, why it matters and how to interpret it.

Investigation order

Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.

01
Site-specific gonorrhoea NAATFirst step
Why
Detect N. gonorrhoeae sensitively from genital, rectal and pharyngeal sites selected by diagnosis and exposure.
Interpretation and limitations
A positive result requires treatment and culture; include pharyngeal testing with every urogenital diagnosis and for every contact.
02
Gonococcal culture and susceptibility
Why
Recover viable organisms before therapy so resistance and alternative antibiotic options can be defined.
Interpretation and limitations
Culture may be less sensitive than NAAT, especially after antibiotics, but is essential for suspected failure and national surveillance.
03
Urethral microscopy
Why
Provide an immediate presumptive diagnosis in a patient with symptomatic penile urethritis.
Interpretation and limitations
Intracellular Gram-negative diplococci are highly supportive in this setting; a negative smear at other sites cannot exclude gonorrhoea.
04
Chlamydia, HIV and syphilis tests
Why
Detect important co-infections and complete an exposure-based sexual-health assessment.
Interpretation and limitations
Interpret negative results against each infection window and repeat when the initial specimen was obtained too soon after exposure.
05
Blood, synovial and mucosal cultures
Why
Confirm disseminated infection and identify susceptibility when systemic or joint features occur.
Interpretation and limitations
Blood culture sensitivity is limited; culture a joint and multiple mucosal sites before antibiotics without delaying urgent parenteral treatment.

06Differential diagnosisRealistic alternatives and the features that help distinguish them.

Chlamydial infection

Chlamydia produces overlapping urethritis and cervicitis, often with less purulence, and requires a different antibiotic when not excluded.

Mycoplasma genitalium

Persistent non-gonococcal urethritis or cervicitis requires resistance-aware molecular testing and an organism-specific regimen rather than repeated empirical ceftriaxone.

Trichomoniasis

Vaginal discharge, dysuria and raised vaginal pH may reflect T. vaginalis, which needs systemic metronidazole and partner treatment.

Non-infective arthritis

Crystal, autoimmune and reactive arthritis can mimic gonococcal joint disease, so aspirate and blood cultures guide urgent therapy.

07ManagementImmediate care, first-line treatment, alternatives and escalation.

01SAMPLESecure sites and susceptibilityFirst stepSymptoms, screening or contact notification creates clinical suspicion of gonorrhoea.

1Record exposure sites and timing, symptoms, pregnancy, previous antibiotics, allergy and any travel or prior resistant infection.
2Take genital, rectal and pharyngeal NAAT as indicated, always adding a pharyngeal sample for a urogenital diagnosis or contact.
3Obtain culture from each suspected or NAAT-positive site before treatment, and add full STI screening with appropriately timed repeats.
4Assess immediately for PID, epididymo-orchitis, ocular disease, septic arthritis or disseminated infection because each changes the regimen.

02TREATGive resistance-aware therapyUncomplicated anogenital or pharyngeal infection is confirmed and susceptibility is not yet known.

1Give ceftriaxone 1 g intramuscularly once and document the exact dose, site, time, allergies and cultures obtained.
2Add chlamydia therapy only when chlamydia has not been excluded, using the current organism-specific and pregnancy-safe regimen.
3AlternativeUse ciprofloxacin only with demonstrated susceptibility and safety review; seek specialist direction for severe cephalosporin allergy or alternative therapy.
4Provide abstinence, partner-notification and complication advice before the patient leaves and name the clinician responsible for results.

03VERIFYTarget test of cureSite, pregnancy, symptoms, susceptibility or chosen therapy meets a 2025 follow-up criterion.

1Arrange test of cure for pharyngeal infection, pregnancy, persistent signs, unknown susceptibility or any non-ceftriaxone treatment.
2If symptomatic, collect culture at least 72 hours after treatment; if asymptomatic, perform NAAT at least two weeks after treatment and culture a positive result.
3Compare pre- and post-treatment susceptibility and sexual history to distinguish likely failure from reinfection or residual nucleic acid.
4EscalationEscalate possible ceftriaxone failure immediately for expert management and applicable national surveillance reporting.

Key medicines and prescribing safety3 treatments · regimens, roles and cautions

Provides the recommended empirical treatment when antimicrobial susceptibility is not yet known.

Ceftriaxone

Give 1 g by intramuscular injection as a single dose for uncomplicated anogenital or pharyngeal gonorrhoea.

Check severe beta-lactam allergy, take cultures first where feasible, and arrange test of cure whenever site, pregnancy, symptoms or susceptibility requires it.

Offers an oral susceptibility-directed option rather than an empirical regimen for gonorrhoea.

Ciprofloxacin

Give 500 mg orally once only when the isolate is susceptible and current specialist guidance supports its use.

Review pregnancy, tendon, neurological, psychiatric, vascular, glycaemic and interacting-medicine risks under current fluoroquinolone restrictions.

Provides a current oral alternative when intramuscular ceftriaxone cannot be used, with lower confidence at the pharynx.

Cefixime alternative

Give 400 mg orally, then a second 400 mg dose six to twelve hours later when this specialist alternative is chosen.

Seek specialist advice, obtain culture, verify adherence and arrange test of cure because treatment differs from ceftriaxone.

08ComplicationsImportant consequences, why they occur and why they matter clinically.

Pelvic inflammatory disease

Ascending cervical infection can inflame endometrium and tubes, leading to abscess, chronic pain, ectopic pregnancy or infertility.

Epididymo-orchitis

Ascending urethral organisms cause epididymal inflammation, with abscess, chronic pain and reproductive impairment in complicated cases.

Disseminated infection

Bacteraemia may produce pustules, tenosynovitis or septic arthritis and requires inpatient parenteral treatment and source control.

Ocular injury

Rapid purulent conjunctival infection can ulcerate and perforate the cornea unless systemic therapy and urgent ophthalmic care begin promptly.

09Monitoring and follow-upTreatment response, safety checks and longer-term review.

Review culture and susceptibility from every positive site and change partner, follow-up or treatment plans when resistance is identified.
Arrange test of cure for pharyngeal infection, pregnancy, persistent symptoms, unknown susceptibility or treatment other than ceftriaxone.
Confirm that symptoms and signs resolve and obtain post-treatment culture promptly if urethral, rectal, ocular or systemic findings persist.
Document partner notification outcomes within the correct two-week or three-month lookback and confirm the seven-day abstinence interval.
Report and manage suspected ceftriaxone failure through specialist microbiology, sexual-health and national surveillance channels.

10Special situationsVariants, exceptions and circumstances that change the usual approach.

NAAT cannot measure susceptibility

Molecular detection identifies infection, while a viable culture supplies the resistance information needed for individual and public-health decisions.

Pharynx needs active testing

The 2025 guideline recommends a throat sample for every urogenital diagnosis and contact because history alone misses pharyngeal carriage.

TOC is conditional

Ceftriaxone-susceptible anogenital infection can avoid routine cure testing, whereas pharyngeal infection and pregnancy cannot.

Positive follow-up has alternatives

Residual nucleic acid, renewed exposure and true antimicrobial failure require different actions, so timing and culture matter.

Resistance changes urgency

Persistent infection after ceftriaxone is both an individual-care problem and a surveillance event requiring immediate expert coordination.

11Common pitfallsFrequent interpretation and management errors.

01
Treating a positive NAAT without first attempting culture from every affected site.
02
Omitting pharyngeal sampling because the patient reports no oral exposure or throat symptoms.
03
Giving ciprofloxacin empirically without demonstrated susceptibility and a fluoroquinolone safety assessment.
04
Applying no-test-of-cure advice to pharyngeal infection, pregnancy, unknown susceptibility or non-ceftriaxone treatment.
05
Interpreting every positive post-treatment NAAT as resistance without checking timing, culture and re-exposure.
06
Managing fever, pustules and a hot joint as uncomplicated mucosal infection rather than possible dissemination.

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