NGU, or Nongonoccocal Urethritis

NGU

Nongonococcal urethritis—or NGU—is an infection of the urethra caused by pathogens (germs) other than gonorrhea. Several kinds of germs can cause NGU, like trichomonas vaginalis or mycoplasma genitalium, but the most common cause is chlamydia. There are nonsexual causes for NGU as well, such as a urinary tract infection or catheterization. NGU is more commonly diagnosed in men than in women.

How is NGU transmitted?

NGU can be passed on through both sexual and non-sexual contact.

Sexual
Most germs that cause NGU can be passed during sex (vaginal, anal or oral) that involves direct mucous membrane contact with an infected person. These germs can be passed even if the penis or tongue does not go all the way into the vagina, mouth or rectum, and even if body fluids aren’t exchanged.

Nonsexual

  • Urinary tract infections.
  • An inflamed prostate gland due to bacteria (bacterial prostatitis).
  • A narrowing or closing of the tube in the penis (urethral stricture).
  • A tightening of the foreskin so that it cannot be pulled back from the head of the penis (phimosa).
  • The result of a process such as inserting a tube into the penis (catheterization).

Perinatal
During birth, infants maybe exposed to the germs causing NGU in passage through the birth canal. This may cause the baby to have infections in the:

  • eyes (conjunctivitis)
  • ears
  • lungs (pneumonia)

What are the symptoms?

For people with a penis (urethral infection)

  • Discharge from the penis
  • Burning or pain when urinating (peeing)
  • Itching, irritation, or tenderness
  • Underwear stain

For people with a vagina (vaginal/urethral infection)
The germs that cause NGU in men might cause other infections in people with vaginas. These might include vaginitis or mucopurulent cervicitis (MPC). The infection may also be asymptomatic (have no symptoms). Symptoms of NGU can include:

  • Discharge from the vagina
  • Burning or pain when urinating (peeing)
  • Abdominal pain or abnormal vaginal bleeding. This may be a sign that the infection has progressed to pelvic inflammatory disease (PID)

Anal or Oral Infections
Anal infection may result in rectal itching, discharge, or pain on defecation. Oral infection may occur. Most (90%) are asymptomatic, but some people might have a sore throat.

How is it diagnosed?

An NGU diagnosis is made when a man has urethritis (inflammation of the urethra), but gonorrhea is ruled out because he has a negative gonorrhea culture and/or gram stain. Other tests include chlamydia culture or urinalysis (sometimes, but rarely).

In women, it may be diagnosed by chlamydia culture. A gonorrhea culture may be done to rule out gonorrhea.

How is NGU treated?

NGU is treated with antibiotics. Some treatments are not appropriate for someone who is pregnant, so someone who is pregnant, or thinks they might be, should inform their health care provider.

Some general treatment guidelines:

  • Take all medications-even if you start to feel better before you finish the bottle.
  • Treat all partners.
  • Inform all partners.
  • Abstain from sex until all partners are treated.
  • Return for evaluation by a health care provider if symptoms persist or if symptoms recur after taking all the prescribed medicine.

What does it mean for my health?

Left untreated, the germs that cause NGU—especially chlamydia—can lead to complications:

People with a penis

  • Epididymitis (inflammation of the epididymis, the elongated structure along the back border of the testes) which can lead to infertility if left untreated.
  • Reiter’s syndrome (arthritis)
  • Conjunctivitis
  • Skin lesions
  • Discharge

People with a uterus

Infections caused by anal sex might lead to severe proctitis (inflamed rectum).

How do I tell my partner?

If you have been told that you have NGU, talk to your partner(s), and let them know so they can be tested and treated. The most common cause of NGU is chlamydia, and it is easy to pass from an infected partner to one who is not infected.

All sex partners of someone diagnosed with NGU should be treated because:

  • They may have an infection and not know it.
  • It keeps them from passing the infection back to you or to others.
  • It prevents them from suffering possible complications.

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