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Infectious Diseases
Sexual Health
Genitourinary Medicine

Gonorrhoea

High EvidenceUpdated: 2025-12-24

On This Page

Red Flags

  • Disseminated Gonococcal Infection (DGI - Septic Arthritis, Tenosynovitis)
  • Pelvic Inflammatory Disease (PID - Infertility Risk)
  • Ophthalmia Neonatorum (Neonatal Conjunctivitis - Blindness)
  • Antimicrobial Resistance
Overview

Gonorrhoea

1. Clinical Overview

Summary

Gonorrhoea is a Sexually Transmitted Infection (STI) caused by the Gram-negative diplococcus Neisseria gonorrhoeae. It is the second most common bacterial STI globally. It primarily infects mucosal surfaces (Urethra, Cervix, Rectum, Pharynx, Conjunctiva). In men, it typically causes purulent urethritis. In women, it often presents as cervicitis, which may be asymptomatic but can ascend to cause Pelvic Inflammatory Disease (PID), leading to infertility, ectopic pregnancy, and chronic pelvic pain. Antimicrobial Resistance (AMR) is a major and increasing concern. Current first-line treatment in the UK is Ceftriaxone 1g IM single dose with mandatory Test of Cure. [1,2]

Clinical Pearls

"The Clap": Men typically present with dysuria and profuse purulent (creamy, yellow-green) urethral discharge. Symptoms are usually obvious, so most seek treatment.

Asymptomatic Women: Up to 50-80% of women are asymptomatic or have vague symptoms. This leads to delayed diagnosis and increased risk of PID.

Check All Sites: Always consider pharyngeal and rectal infection, especially in MSM. Pharyngeal infection is often asymptomatic but is a reservoir for transmission and resistance.

Antimicrobial Resistance is Critical: Gonorrhoea has developed resistance to almost every antibiotic used against it. Ciprofloxacin is no longer first-line (resistance >20% in UK). Azithromycin is no longer co-prescribed (resistance concerns). Follow local guidelines.

2. Epidemiology

Demographics

  • Incidence (UK): ~70,000 cases per year (rising significantly).
  • Age: Peak 15-25 years.
  • Sex: More symptomatic in males, so higher diagnosed rates. Females often asymptomatic.
  • Risk Groups: Young adults, Men who have Sex with Men (MSM), Multiple sexual partners, Inconsistent condom use, Concurrent STIs.

Co-Infection

  • High rates of Chlamydia co-infection (10-40%). Test for both.
3. Pathophysiology

Mechanism

  1. Attachment: N. gonorrhoeae attaches to columnar and transitional epithelial cells via Pili (Type IV).
  2. Invasion: Bacteria invade non-ciliated epithelial cells via Opa proteins and Porin proteins.
  3. Inflammation: Triggers intense neutrophilic inflammatory response. This produces the characteristic purulent discharge.
  4. Tissue Damage: Lipooligosaccharide (LOS) endotoxin contributes to epithelial damage.
  5. Spread: Can spread locally (e.g., Cervix -> Endometrium -> Fallopian Tubes = PID) or haematogenously (Disseminated Gonococcal Infection = DGI).

Immune Evasion

  • Neisseria has remarkable ability to evade immunity: Antigenic variation of Pili, Opa proteins, and LOS means reinfection is common. There is no protective immunity.
4. Differential Diagnosis (Urethritis / Cervicitis)
ConditionKey Features
Chlamydia trachomatisSimilar presentation but often milder discharge (mucopurulent, less profuse). Most common bacterial STI. NAAT positive.
Mycoplasma genitaliumEmerging pathogen. Urethritis, Cervicitis, PID. Increasingly resistant.
Trichomonas vaginalisProtozoan. Frothy, yellow-green, malodorous discharge (Women). Often asymptomatic in men. Wet prep microscopy.
Herpes Simplex (HSV)Genital ulcers rather than discharge. Pain, dysuria.
Non-Specific Urethritis (NSU)Urethritis without identified Chlamydia/Gonorrhoea. May be due to Mycoplasma, Ureaplasma, or unknown.
UTIMid-stream urine positive. May coexist.
5. Clinical Presentation

Male Urogenital Infection

Female Urogenital Infection

Extragenital Infection

Disseminated Gonococcal Infection (DGI) (Rare)

Ophthalmia Neonatorum

Symptoms
Dysuria, Purulent urethral discharge (typically profuse, yellow-green). Urethral discomfort.
Signs
Mucopurulent/purulent meatal discharge.
Timing
Symptoms usually 2-5 days after exposure (can be up to 30 days).
Symptomatic Rate
~90% develop symptoms.
6. Investigations

Nucleic Acid Amplification Test (NAAT) - Gold Standard

  • Sample: Self-collected Vulvo-Vaginal Swab (Women), First-Void Urine (Men). Pharyngeal and Rectal swabs (if indicated by history).
  • Sensitivity/Specificity: Excellent (>95%).
  • All positive NAATs should have a specimen sent for Culture and Sensitivity (to monitor AMR).

Microscopy and Culture

  • Microscopy: Gram stain of urethral/endocervical swab. See Gram-negative intracellular diplococci within neutrophils. Sensitivity variable.
  • Culture: Essential for AMR surveillance. Requires specific transport media (e.g., Charcoal Swab) and rapid transit.

Test of Cure (TOC)

  • Mandatory for all gonorrhoea cases due to AMR concerns.
  • Repeat NAAT 2 weeks (NAAT) or 1 week (Culture) after treatment.

Screen for Other STIs

  • Chlamydia (NAAT).
  • HIV (4th Generation).
  • Syphilis (Serology).
  • Hepatitis B (Consider vaccination).
7. Management

Management Algorithm

           GONORRHOEA DIAGNOSED (NAAT+)
                      ↓
           SEND FOR CULTURE & SENSITIVITY
           (Before or ASAP after treatment)
                      ↓
           TREAT IMMEDIATELY (Epidemiological Rx)
           - CEFTRIAXONE 1g IM (Stat)
                      ↓
           PATIENT COUNSELLING
           - Abstinence for 7 days post-Tx
           - Partner notification essential
           - Avoid sex until partner treated
                      ↓
           TEST OF CURE (TOC)
           - 2 weeks post-Tx (NAAT)
           - 1 week if Culture
                      ↓
           PARTNER NOTIFICATION & TREATMENT
           (Contact Tracing)

First-Line Treatment (UK BASHH 2019/Updated)

  • Ceftriaxone 1g Intramuscular (IM) Single Dose.
  • Dilute in Lidocaine 1% to reduce pain of injection.
  • Azithromycin is NO LONGER routinely added (to preserve its efficacy for Mycoplasma and concerns about resistance).

Special Situations

  • Pharyngeal Gonorrhoea: Ceftriaxone 1g IM (Same regimen, harder to eradicate).
  • DGI / Septic Arthritis: Ceftriaxone 1g IV/IM daily until 24-48h after clinical improvement, then oral switch (total 7-14 days).
  • Ophthalmia Neonatorum: Ceftriaxone 25-50mg/kg (max 125mg) IM single dose + Saline irrigation. Ophthalmology review.
  • Pregnancy: Ceftriaxone 1g IM is safe.
  • Cephalosporin Allergy: Spectinomycin 2g IM (if available) or Gentamicin 240mg IM + Azithromycin 2g oral. Consult specialist.

Partner Notification (Contact Tracing)

  • Essential to break transmission chain.
  • Advise patient to notify all sexual partners within the preceding 2 weeks (if symptomatic) or 3 months (if asymptomatic).
  • Partners should be tested and treated epidemiologically.
8. Complications

Male

  • Epididymo-orchitis.
  • Urethral Stricture (Chronic).
  • Prostatitis (Rare).

Female

  • Pelvic Inflammatory Disease (PID): Ascending infection. Risk of Tubal scarring, Infertility, Ectopic pregnancy, Chronic pelvic pain.
  • Bartholinitis: Abscess of Bartholin's gland.
  • Fitz-Hugh-Curtis Syndrome: Perihepatitis (Right upper quadrant pain).

Disseminated (Both)

  • DGI: Arthritis-Dermatitis Syndrome, Septic Arthritis, Tenosynovitis.
  • Endocarditis, Meningitis: Rare but serious.

Neonatal

  • Ophthalmia Neonatorum: Can cause blindness.
9. Prognosis and Outcomes
  • Excellent with treatment: Ceftriaxone cure rate >95% for uncomplicated infection.
  • PID: Even with treatment, ~18% develop chronic pelvic pain, 10% become infertile, 1% have ectopic pregnancy.
  • Reinfection: Common if partners not treated or high-risk behaviour continues.
10. Evidence and Guidelines

Key Guidelines

GuidelineOrganisationKey Recommendations
GonorrhoeaBASHH (2019, Updated)Ceftriaxone 1g IM single dose. Test of Cure mandatory. Azithromycin no longer routine.
STI ScreeningNICE / PHEOpportunistic screening in high-risk groups.

Antimicrobial Resistance

  • Gonorrhoea has developed resistance to: Sulphonamides, Penicillin, Tetracycline, Fluoroquinolones (Ciprofloxacin), Macrolides (Azithromycin).
  • GRASP (Gonococcal Resistance to Antimicrobials Surveillance Programme): Monitors UK resistance.
  • Ceftriaxone remains effective but reduced susceptibility strains are emerging globally (e.g., "Super-Gonorrhoea").
11. Patient and Layperson Explanation

What is Gonorrhoea?

Gonorrhoea (sometimes called "The Clap") is a common infection passed through sex. It's caused by a type of bacteria.

What are the symptoms?

  • Men: Usually get a thick, yellow-green discharge from the penis and pain when peeing.
  • Women: Often have no symptoms at all, which is why it's important to get tested if at risk. It can cause unusual discharge or bleeding.
  • It can also infect the throat or back passage (rectum), often without symptoms.

Why is it important to treat?

  • If untreated, it can spread to other parts of the body and cause serious problems like infertility (especially in women), joint infections, and problems for babies during childbirth.
  • It also makes you more likely to get or pass on HIV.

How is it treated?

  • A single injection of an antibiotic (Ceftriaxone) cures it.
  • You must avoid sex for 7 days after treatment AND until your partner(s) have been treated.
  • You'll need a "Test of Cure" blood test a couple of weeks later to make sure it's gone.

What about my partner(s)?

  • It's really important that your recent sexual partners are told, so they can get tested and treated too. The clinic can help with this (anonymously if needed).
12. References

Primary Sources

  1. BASHH. UK National Guideline for the Management of Gonorrhoea in Adults. 2019 (Updated).
  2. PHE. GRASP Report: Gonococcal Resistance to Antimicrobials Surveillance Programme. 2023.
13. Examination Focus

Common Exam Questions

  1. Organism: "Gram stain appearance?"
    • Answer: Gram-negative Intracellular Diplococci (Kidney-bean shaped pairs inside neutrophils).
  2. Treatment: "First-line treatment UK?"
    • Answer: Ceftriaxone 1g IM single dose.
  3. Complication: "Why screen and treat women aggressively?"
    • Answer: Often asymptomatic. Risk of ascending PID leading to Tubal damage, Infertility, Ectopic Pregnancy.
  4. Public Health: "What is Test of Cure?"
    • Answer: Repeat NAAT 2 weeks post-treatment to confirm eradication. Mandatory due to AMR.

Viva Points

  • Antimicrobial Resistance: Discuss the history of resistance development and the importance of GRASP surveillance. Explain why Azithromycin is no longer routinely co-prescribed.
  • Ophthalmia Neonatorum: Explain the pathogenesis (birth canal) and the severity (blindness) and emergency treatment.

Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists.

Last updated: 2025-12-24

At a Glance

EvidenceHigh
Last Updated2025-12-24

Red Flags

  • Disseminated Gonococcal Infection (DGI - Septic Arthritis, Tenosynovitis)
  • Pelvic Inflammatory Disease (PID - Infertility Risk)
  • Ophthalmia Neonatorum (Neonatal Conjunctivitis - Blindness)
  • Antimicrobial Resistance

Clinical Pearls

  • **"The Clap"**: Men typically present with dysuria and profuse purulent (creamy, yellow-green) urethral discharge. Symptoms are usually obvious, so most seek treatment.
  • **Asymptomatic Women**: Up to 50-80% of women are asymptomatic or have vague symptoms. This leads to delayed diagnosis and increased risk of PID.
  • **Check All Sites**: Always consider pharyngeal and rectal infection, especially in MSM. Pharyngeal infection is often asymptomatic but is a reservoir for transmission and resistance.
  • Fallopian Tubes = PID) or haematogenously (Disseminated Gonococcal Infection = DGI).

Guidelines

  • NICE Guidelines
  • BTS Guidelines
  • RCUK Guidelines