OVERVIEW

What is non-gonococcal urethritis?

Non-gonococcal urethritis (NGU), as the name suggests, refers to urethritis caused by pathogens other than Neisseria gonorrhoeae.

Gonorrhea is a sexually transmitted disease caused by gonococcus, a Gram-negative (red) coccus that leads to purulent infections, primarily affecting the urinary and reproductive tracts.

Other pathogens besides gonococcus can also cause acute or chronic inflammation of the urogenital tract. This article focuses on the main pathogens, including Chlamydia trachomatis, Mycoplasma genitalium, and Ureaplasma urealyticum. Urethritis caused by Trichomonas vaginalis or Candida is generally classified under other diseases.

Is non-gonococcal urethritis common?

Yes, it is prevalent in China and ranks first in incidence among the eight legally monitored sexually transmitted diseases.

SYMPTOMS

What symptoms do patients with non-gonococcal urethritis experience?

Approximately 20%–50% of male patients show no obvious clinical symptoms. Symptomatic infections primarily manifest as discomfort during urination, accompanied by increased urethral discharge, which may be serous or seropurulent. Female patients often exhibit less typical clinical manifestations than males, with a higher proportion of asymptomatic infections—around 70%.

In the early stages, typical patients may experience urethral itching, pain, or a burning sensation. Some may also have frequent urination or painful urination, with mild redness and swelling at the urethral opening and a small amount of mucus discharge. Some patients may notice the urethral opening sealed by a membrane formed from dried secretions (the "sticky orifice" phenomenon) upon waking, along with visible stains on their underwear.

Female patients may also develop cervicitis, in which case vaginal discharge becomes infectious.

What other diseases can non-gonococcal urethritis cause?

Non-gonococcal urethritis may lead to complications such as Reiter's syndrome and ankylosing spondylitis. These conditions are associated with immune abnormalities triggered by mycoplasma infections.

Can non-gonococcal urethritis progress to chronic infection?

Yes, non-gonococcal urethritis can become a chronic infection. While symptoms may lessen in chronic cases, the condition can persist for years, making treatment more difficult.

CAUSES

What causes non-gonococcal urethritis?

The main cause of non-gonococcal urethritis is infection by specific pathogenic microorganisms, such as Mycoplasma genitalium, Ureaplasma urealyticum, and Chlamydia trachomatis.

Is non-gonococcal urethritis contagious?

Yes, it is contagious and can spread through three main routes:

• Sexual contact transmission: Non-gonococcal urethritis is a sexually transmitted disease primarily spread through sexual contact, including vaginal, anal, and oral sex.
• Indirect contact transmission: Indirect contact can also transmit non-gonococcal urethritis. Patients can shed secretions containing Mycoplasma or Chlamydia, which are infectious. Therefore, healthy individuals may contract the infection if their urogenital areas or eyes come into contact with contaminated objects or body parts (especially hands).
• Vertical mother-to-child transmission: If a pregnant woman has non-gonococcal urethritis, she can transmit Mycoplasma or Chlamydia to the newborn during childbirth.

Which groups are more susceptible to non-gonococcal urethritis?

Non-gonococcal urethritis is primarily transmitted through sexual contact, so sexually active individuals (mainly young adults) are more likely to contract it. Women can also acquire it through indirect contact.

Additionally, young children, especially girls, who require assistance with daily activities (such as toileting, bathing, or dressing) are at risk of infection from caregivers.

How can patients with non-gonococcal urethritis estimate when they were infected?

The incubation period for non-gonococcal urethritis is 1–3 weeks. Therefore, the infection likely occurred through sexual or indirect contact within the past three weeks.

Why might a patient with non-gonococcal urethritis get infected even without recent sexual intercourse?

The incubation period for non-gonococcal urethritis is 1–3 weeks, so sexual contact within this timeframe could still lead to infection.

Moreover, the infectious secretions of non-gonococcal urethritis can spread through intimate contact, such as touching genital areas, even without intercourse.

If a patient with non-gonococcal urethritis had no symptomatic sexual partners in the past 3 weeks, where did the infection come from?

Many people with non-gonococcal urethritis show mild or no symptoms, so the patient’s partners may have been asymptomatic carriers. Sexual transmission remains a likely source.

In rare cases, indirect contact transmission could also be responsible.

After recovering from non-gonococcal urethritis, is the patient immune to future infections?

No. The human body does not develop permanent immunity to Mycoplasma or Chlamydia. Re-exposure to these pathogens can lead to reinfection.

Can non-gonococcal urethritis infect areas other than the urethra or genital tract?

Yes.

Besides the urethra and cervix, Mycoplasma and Chlamydia can infect the epididymis (men), prostate (men), Bartholin’s glands (women), endometrium (women), fallopian tubes (women), pelvic cavity (women), and rectal mucosa.

Chlamydia trachomatis can also infect the throat mucosa, particularly in those who engage in oral sex. Rubbing the eyes with contaminated hands can lead to conjunctivitis. Newborns may contract Ureaplasma urealyticum pneumonia or Chlamydia trachomatis conjunctivitis during childbirth.

DIAGNOSIS

What tests are needed to diagnose nongonococcal urethritis?

Tests such as urinalysis, microscopic examination of secretions, mycoplasma culture and drug sensitivity testing, and Chlamydia trachomatis antigen detection are required.

How is nongonococcal urethritis diagnosed?

The diagnosis is based on sexual contact history, symptoms of urethritis or cervicitis, and microscopic examination of secretions to rule out gonorrhea. Mycoplasma culture or Chlamydia trachomatis antigen detection can confirm the diagnosis.

Which diseases are easily confused with nongonococcal urethritis?

Nongonococcal urethritis is often confused with gonorrhea.

Gonorrhea is caused by Neisseria gonorrhoeae infecting the urethra and is also a sexually transmitted disease. Patients with gonorrhea are often co-infected with both nongonococcal urethritis and gonorrhea.

Compared to nongonococcal urethritis, gonorrhea symptoms are more severe, but clinical symptoms alone often cannot distinguish them. Microscopic examination of secretions is needed to rule out gonorrhea.

TREATMENT

Which department should patients suspected of having non-gonococcal urethritis visit?

If you notice the aforementioned symptoms and suspect non-gonococcal urethritis, you should visit the dermatology and venereology department, urology department, or infectious diseases department. Depending on gender, you may also seek care at the andrology or gynecology department.

How is non-gonococcal urethritis treated?

Treatment primarily involves antibacterial medications such as levofloxacin, moxifloxacin, roxithromycin, azithromycin, or minocycline.

The attending doctor will determine the specific medication, dosage, and treatment duration based on individual circumstances, the condition, and laboratory test results. Patients must strictly follow the prescribed treatment.

Does non-gonococcal urethritis require hospitalization?

Non-gonococcal urethritis is generally mild and can be treated on an outpatient basis without hospitalization. However, if severe complications such as Reiter's syndrome or ankylosing spondylitis occur, the doctor may require hospitalization.

Can non-gonococcal urethritis be completely cured?

With proper treatment, non-gonococcal urethritis can be completely cured.

How is non-gonococcal urethritis considered cured?

After treatment, if symptoms disappear and routine urine or vaginal discharge tests show no signs of inflammation in the genitourinary system, the condition is considered cured.

Are there any sequelae after curing non-gonococcal urethritis?

In cases of prolonged illness, infection spreading to the reproductive system, or severe conditions, sequelae such as infertility may occur after recovery.

Do sexual partners of non-gonococcal urethritis patients need to seek medical attention?

All sexual partners of the patient within the 3 weeks prior to the onset of symptoms should be notified to seek medical examination to check for infection.

If a non-gonococcal urethritis patient is found to be infected with Chlamydia trachomatis during a checkup but has no symptoms, is treatment necessary?

Yes. Even without obvious symptoms, Chlamydia trachomatis can still damage the body, so active treatment is recommended.

If a non-gonococcal urethritis patient is found to be infected with Mycoplasma during a checkup but has no symptoms, is treatment necessary?

Some studies suggest that certain strains of Mycoplasma genitalium or Ureaplasma urealyticum may be "harmless" colonizers in humans, and whether symptoms develop may depend on the serotype and individual differences.

Therefore, if Mycoplasma infection is detected during a checkup but there are no symptoms and no signs of genitourinary inflammation in laboratory tests, treatment may not be necessary.

DIET & LIFESTYLE

What should patients with non-gonococcal urethritis pay attention to in their diet?

No special dietary adjustments are necessary.

What should patients with non-gonococcal urethritis pay attention to in their daily life after contracting the disease?

Non-gonococcal urethritis is primarily transmitted through sexual contact, but indirect contact may also spread the infection. Patients should avoid sexual contact with others, sleep separately, and wash hands frequently. Their clothing and towels should be washed separately and disinfected with laundry sanitizer to prevent the spread of pathogens.

What should cohabitants of non-gonococcal urethritis patients pay attention to?

Cohabitants of non-gonococcal urethritis patients should sleep separately, wash hands frequently, and avoid sharing personal hygiene items with the patient.

PREVENTION

How to prevent non-gonococcal urethritis?

Avoid promiscuity and use condoms correctly to reduce and prevent the transmission of non-gonococcal urethritis.