Gonorrhea
Gonorrhea is a common sexually transmitted infection (STI) caused by the Gram-negative diplococcus Neisseria gonorrhoeae. It primarily infects mucous membranes of the urethra, cervix, rectum, pharynx, and conjunctiva, leading to various clinical manifestations depending on the site of infection. In females, it can remain asymptomatic, allowing the disease to progress silently, whereas in males, it often presents with characteristic urethral discharge and dysuria.
Known since ancient times and historically referred to as “the clap,” gonorrhea continues to represent a major global public health burden. Untreated, it can lead to severe complications such as pelvic inflammatory disease (PID), infertility, ectopic pregnancy, and in neonates, ophthalmia neonatorum. Alarmingly, the emergence of multi-drug resistant (MDR) strains of N. gonorrhoeae is now recognized as a critical global health threat.
Symptoms
In Men (usually symptomatic):
- Burning pain during urination (dysuria).
- Purulent (thick, yellow/green) urethral discharge.
- Pain or swelling in one testicle (epididymitis).
In Women (often asymptomatic or mild):
- Increased vaginal discharge.
- Painful urination.
- Intermenstrual bleeding.
- Pelvic or abdominal pain (may indicate pelvic inflammatory disease – PID).
Other sites:
- Rectal gonorrhea: Anal itching, discharge, pain.
- Pharyngeal gonorrhea: Sore throat (often asymptomatic).
- Eye infection: Redness, pain, pus discharge.
2. Definition
Gonorrhea is defined as a bacterial infection of the urogenital tract, anorectal region, pharynx, or eyes caused by Neisseria gonorrhoeae, primarily transmitted through sexual contact or from mother to child during childbirth. The bacterium primarily affects the epithelial surfaces and has a particular affinity for columnar and transitional epithelial cells.
Pathophysiology of Gonorrhea
Step 1: Entry of Bacteria
Gonorrhea is caused by Neisseria gonorrhoeae, a gram-negative diplococcus. It usually spreads through sexual contact and enters the body through the mucous membranes of the urethra, cervix, rectum, throat, or eyes.
Step 2: Attachment to Mucosa
The bacteria use special structures called pili (fimbriae) and outer membrane proteins to attach firmly to the epithelial cells of the genital or urinary tract. This prevents them from being washed away by urine or secretions.
Step 3: Invasion of Cells
After attachment, the bacteria penetrate into the epithelial cells. They multiply inside and cause damage to the lining of the mucosa. This invasion triggers an inflammatory response from the host’s immune system.
Step 4: Inflammatory Reaction
The immune system sends neutrophils to the site of infection. The fight between bacteria and immune cells leads to pus formation (thick yellow or green discharge). The inflammation also causes burning during urination, pain, and swelling.
Step 5: Local and Ascending Spread
- In men, the infection usually stays in the urethra but can spread to the epididymis, causing testicular pain.
- In women, the bacteria may ascend to the uterus and fallopian tubes, leading to pelvic inflammatory disease (PID). This can cause abdominal pain, fever, and infertility due to scarring.
Step 6: Complications and Dissemination
If untreated, the bacteria can spread into the bloodstream (disseminated gonococcal infection). This may cause skin rashes, joint pain, and arthritis. In newborns exposed during childbirth, gonorrhea can infect the eyes, leading to neonatal conjunctivitis and blindness if not treated.
Bacteria enter through mucosa → attach and invade → inflammation with pus → local spread (urethritis, PID) → possible bloodstream spread → systemic complications.
3. Epidemiology of Gonorrhea
3.1 Global Scenario
According to the World Health Organization (WHO):
- Over 82 million new cases of gonorrhea were reported globally in 2020.
- It is among the top four curable STIs along with chlamydia, syphilis, and trichomoniasis.
- The highest rates are observed in individuals aged 15 to 29 years, especially among sexually active adolescents and young adults.
3.2 Indian Perspective
- India has seen a steady rise in STI prevalence due to increasing urban migration, lack of awareness, and poor condom use.
- NACO (National AIDS Control Organization) lists gonorrhea as one of the major RTI/STIs diagnosed in clinical settings.
3.3 Risk Factors
- Multiple sexual partners
- Inconsistent or incorrect condom use
- Existing co-infection with other STIs
- Commercial sex work
- Immunocompromised states (e.g., HIV-positive individuals)
4. Etiology of Gonorrhea
Neisseria gonorrhoeae, the causative agent, is:
- A Gram-negative, kidney-bean-shaped diplococcus
- Oxidase-positive, catalase-positive
- Non-motile but uses pili and surface proteins for adhesion and invasion
- Facultative intracellular pathogen—able to survive and multiply inside neutrophils
- Grows best in 5–10% CO₂ atmosphere on chocolate agar or Thayer-Martin medium
5. Transmission of Gonorrhea
Transmission occurs mainly via sexual contact, including:
- Vaginal and anal intercourse
- Oral sex
- Vertical transmission – from infected mother to newborn during delivery
- Rarely through fomites due to the bacterium’s inability to survive long outside the body
6. Pathogenesis of Gonorrhea
- Attachment: Bacteria adhere to epithelial cells via pili and Opa proteins.
- Invasion: Penetration into epithelial cells and evasion of host defenses.
- Immune Evasion: Through antigenic variation, inhibition of phagolysosomal fusion, and secretion of IgA proteases.
- Inflammation: Induces robust neutrophilic response, resulting in purulent discharge and tissue damage.
- Dissemination (in some cases): May enter the bloodstream causing Disseminated Gonococcal Infection (DGI).
7. Clinical Manifestations
Gonorrhea may be asymptomatic in up to 50% of females and 10% of males. Symptomatology depends on the site of infection:
7.1 In Males
- Urethritis: Burning sensation during urination (dysuria), profuse purulent yellow-green urethral discharge
- Epididymitis: Testicular pain and swelling
- Proctitis (in MSM): Rectal pain, discharge, bleeding
7.2 In Females
- Cervicitis: Vaginal discharge, intermenstrual bleeding, post-coital bleeding
- Urethritis: Dysuria and frequency
- Pelvic Inflammatory Disease (PID): Fever, lower abdominal pain, adnexal tenderness, infertility
- Bartholinitis: Inflammation of Bartholin glands
7.3 In Both Sexes
- Pharyngitis: Sore throat following oral sex
- Conjunctivitis: Especially in neonates (ophthalmia neonatorum)
- Arthritis-Dermatitis Syndrome: Migratory arthritis, skin lesions, and tenosynovitis in DGI
7.4 In Newborns
- Ophthalmia neonatorum: Severe eye infection acquired during delivery; can lead to blindness if untreated.
8. Diagnosis of Gonorrhea
8.1 Microscopy
- Gram stain of urethral discharge: Shows intracellular Gram-negative diplococci in males with symptomatic urethritis—sensitivity >95%.
- Less reliable in females due to normal flora interference.
8.2 Culture
- Performed on Thayer-Martin selective medium.
- Confirms the organism and enables antibiotic sensitivity testing.
8.3 Nucleic Acid Amplification Tests (NAATs)
- Highly sensitive and specific
- Can detect both N. gonorrhoeae and Chlamydia trachomatis simultaneously.
- Specimens: First-catch urine, vaginal/cervical swabs, pharyngeal or rectal swabs.
8.4 Serological Tests
- Not routinely used; no role in diagnosing active infection.
9. Differential Diagnosis
- Chlamydia trachomatis infection
- Non-gonococcal urethritis
- Trichomoniasis
- Bacterial vaginosis
- Herpes simplex virus (HSV) infection
10. Treatment of Gonorrhea
Due to emerging antibiotic resistance, current guidelines focus on dual therapy:
10.1 Uncomplicated Gonorrhea (Urethral, Cervical, Rectal, Pharyngeal)
As per CDC (2023) and WHO recommendations:
- Ceftriaxone 500 mg IM single dose
- If weight >150 kg: 1 g IM single dose
- Plus treatment for Chlamydia (if not ruled out):
- Doxycycline 100 mg orally twice daily for 7 days
Alternative (only if allergic to cephalosporins):
- Gentamicin 240 mg IM + Azithromycin 2 g orally (less effective)
10.2 Disseminated Gonococcal Infection (DGI)
- Ceftriaxone 1 g IV every 24 hours for 7–14 days
- Oral switch to cefixime after improvement
- Joint drainage if septic arthritis
10.3 Ophthalmia Neonatorum
- Ceftriaxone 25–50 mg/kg IV or IM, single dose (max 125 mg)
10.4 Pelvic Inflammatory Disease (PID)
- Ceftriaxone 500 mg IM single dose
- Plus Doxycycline + Metronidazole for 14 days
11. Prevention and Control
- Barrier protection: Consistent and correct condom use
- Screening programs: Regular STI screening for high-risk groups
- Partner notification and treatment: To prevent reinfection and community spread
- Neonatal prophylaxis: Erythromycin eye ointment at birth
- Sexual abstinence during treatment and 7 days after
- Education campaigns: Raising awareness about safe sexual practices
12. Complications
Untreated gonorrhea may lead to:
- Epididymitis and infertility in men
- PID, tubo-ovarian abscess, ectopic pregnancy in women
- Infertility
- Chronic pelvic pain
- Ophthalmia neonatorum
- Disseminated gonococcal infection (DGI)
13. Antibiotic Resistance: A Global Threat
- Resistance reported to penicillin, tetracycline, ciprofloxacin, and even extended-spectrum cephalosporins.
- Gonorrhea is now a “superbug” candidate.
- Research is ongoing for new antimicrobials and a potential vaccine.
Conclusion
Gonorrhea remains a highly prevalent STI worldwide, with a growing challenge due to antimicrobial resistance. Early diagnosis, prompt treatment, and effective public health measures such as partner tracing, condom promotion, and STI education are pivotal in controlling the spread of gonorrhea. Clinicians must stay updated on changing resistance patterns and adopt recommended dual therapy regimens to ensure successful treatment outcomes. Preventing and managing gonorrhea also plays a crucial role in reducing HIV transmission, improving reproductive health, and safeguarding neonatal well-being.
