Can Non-Gonococcal Urethritis (NGU) be non-STD?

Non-Gonococcal Urethritis (NGU) is a common syndrome seen in men. Often, NGU is assumed to be caused by underlying STDs and causing relationship disharmony between couples- especially when no final causative bacteria/virus can be ‘pinned down’ following elaborative STD testing.

In this article, we want to understand the term NGU and explore whether NGU can be non-STD related. So brace yourself and read on.

What is Non-Gonococcal Urethritis (NGU)?

Non-Gonococcal Urethritis (NGU) or non-Specific urethritis (NSU) is a medical condition involving the inflammation of the urethra that is not caused by Neisseria gonorrhoeae bacteria. The urethra is the tube that connects the bladder to the external body, allowing the urine to be excreted out of the body system. 

Although NGU can affect anyone, it is more common in male. In female sexual partner, one can be affected by similar infection yet one can be asymptomatic.

Approximately two-thirds of NGU cases are due to underlying STDs with chlamydia trachomatis and mycoplasma genetalium bacteria being the most common bacteria associated with STD-related NGU.

Unfortunately, one-third of NGU cases have to causative found following medical investigations and can be due to non-STD causes including irritation or contact chemicals to affected area.

What are the symptoms of NGU?

One with NGU commonly presented with abnormal urinary symptoms such as

• Painful urination
• Penile discharge
• Irritation during urination
• Genital itching
• Painful ejaculation
• Red rashes over the penis or genital

In more severe case, on may also experience

• Lower pelvic pain
• Testicular/scrotal pain or swelling
• Fever
• Fertility issues

The symptoms of NGU are similar with symptoms with gonorrhea infection (yet, it is not due to gonorrhea, hence the name NGU!)

What are the causes of NGU?

NGU is an umbrella term for medical condition related to the inflammation of the urethra. NGU can be broadly categorised into STD related (which is common) vs non-STD related.

STD related causes of NGU

This involves various bacteria and virus that can be contracted through intercourse to body fluid-mucous-blood transmission.

As mentioned, Chlamydia trachomatis, Mycoplasma genetalium comprises most of the cases of NGU.

Common pathogens responsible include

• Chlamydia trachomatis
• Trichomonas vaginalis
• Mycoplasma genetalium
• Herpes Simplex Virus 1 and 2
• Haemophilus vaginalis
• Ureaplasma urealyticum
• Ureaplasma parvum
• Adenovirus

Non-STD related causes of NGU

• Urinary tract related bacterial infection
• Trauma
• Structural causes- tight foreskin, narrowing of the urethra
• Recent medical instrumentation such as catheterisation

The association of male NGU and female partner with bacterial-vaginosis-related bacteria

Men who has female sexual partner(s) with bacterial vaginosis (BV) have a higher risk of developing of NGU. Clinical studies have shown that bacterial vaginosis-related bacteria such as Gardnerella vaginalis, Prevotella spp, Ureaplasma urealyticum, Ureplasma parvum can trigger or cause NGU symptoms in men sexual partner. Viral shredding of herpes simplex virus (HSV-1 and HSV-2) can also trigger male NGU from sexual partner(s).

This highlights the importance of ensuring female sexual partner(s) taking care of their general health as well. Despite one may have minimal symptoms, or ‘discharge that is considered normal/monthly’, female partners may consider regular checkup and treatment to ensure healthy microflora. As a consequent, the occurrence and trigger of male NGU can be avoided.

The association of male NGU with oral-genital exposure-related bacteria and viruses

Occurrence of NGU in men can also be associated with bacteria or viruses exposed following received oral intercourse. Chlamydial bacterial infection remains the most common culprit causing NGU cases.

Infections such as herpes simplex virus (HSV-1), adenovirus can be passed on through oral intercourse resulting in urethritis symptoms in men. Sometimes, oral sex can be associated with NGU inflammation without identifiable pathogens/bacteria.

What is the complications if NGU is left untreated?

• If the NGU is due to underlying STDs and is unattended, the infection can extend to surrounding reproductive organs, causing infection of the testis (epididymitis) and prostate (prostatitis) etc.
• Over long time, chronic inflammation and infection from untreated STD can cause scaring of the reproductive organ resulting in infertility in men.
• Rarely, one can develop other organ (reactive) complications causing joint infections and swelling, red eyes, and unusual body skin rash
• STD-related NGU can be transmitted to women leading to pelvic inflammatory disease and infertility in women.

If you suspect you have NGU/ NGU-related symptoms, do reach out to your healthcare providers as STD-related NGU is treatable with the right medication and right dose-duration of medication.

How can I get screened for NGU?

Your healthcare provider will usually obtain a sexual history and other relevant medical history of your symptoms. A physical examination involving genital examination is usually offered to examine for any rash, ulcers, lumps, lymph nodes and discharges. Depending on individual’s clinical suspicion, your doctor may offer urine test, swab test (penile if male or vaginal if female) or even blood tests to evaluate your condition and screen for NGU causes.

What is the treatment for NGU?

For STD-related NGU or infection-related NGU, your doctor may prescribe antibiotics to eradicate underlying infections (if any). One will require follow up review after treatment as occasionally some patients may require more than 1 course of medication treatment due to persistent symptoms.

If the underlying cause is related to STDs, your partner is advisable to get screened and treated if needed. You should abstain from any form of sexual intercourse until you have finished your antibiotics and your symptoms have resolved. This is imperative to break the vicious cycle of re-infections between sexual partner(s).

How can I avoid having a repeat infection of NGU?

• Practising safe sex is always key.

• Barrier contraception is advisable during intercourse- for vaginal, anal, or even oral intercourse.
• If you or your partner(s) have abnormal genital symptoms or suspicion of NGU/STD, avoid sexual contact.
• It is always good practice to get screened for STDs before getting involved in a sexual relationship with your new partner(s).
• Regular STD screening if you are sexually active.

Final words…

• Commonly NGU is related to STD infections, though NGU can also be non-STD related. No identifiable causative pathogens can be found in some cases of NGU.
• NGU symptoms can be similar to gonorrhea infective symptoms.
• Men who receive oral intercourse have risk of developing NGU.
• NGU can be screened, treated, and will require follow up to ensure complete recovery of symptoms.
• Safe sex is vital to prevent NGU.

If you have symptoms or concerns about NGU, speak with our doctors at Dr. Ben Medical Clinic to discuss your options and get the support you need. Contact us to make an appointment.

References:

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2. Frølund M, Falk L, Ahrens P, Jensen JS. Detection of ureaplasmas and bacterial vaginosis associated bacteria and their association with non-gonococcal urethritis in men. PLoS ONE. 2019; 14(4): e0214425.
   
3. Frølund M, Wikström A, Lidbrink P, Abu Al-Soud W, Larsen N, Harder CB, Sørensen SJ, Jensen JS, Ahrens P. The bacterial microbiota in first-void urine from men with and without idiopathic urethritis. PLoS One. 2018 Jul 27;13(7):e0201380.
   
4. Bradshaw CS, Tabrizi SN, Read TRH, Garland SM, Hopkins CA, Moss LM, Fairley CK. Etiologies of Nongonococcal Urethritis: Bacteria, Viruses, and the Association with Orogenital Exposure. The Journal of Infectious Diseases. 2006 (feb); 193(3);336-345.
   
5. Schwartz MA, Lafferty WE, Hughes JP, Handsfield HH. Risk factors for urethritis in heterosexual men. The role of fellatio and other sexual practices. Sex Transm Dis. 1997 Sep;24(8):449-55.