What is penile discharge?

By Dr. Kizito Lubano

Penile discharge is the abnormal loss of fluid that is not urine, or semen from the urethra (urine tube) at the tip of the penis.

It is commonly the sign of a sexually transmitted disease (STD), and it requires prompt and accurate diagnosis and treatment, usually by staff at a specialist genitourinary medicine (GUM) or STD clinic.

Symptoms
The discharge can vary in amount from scanty to profuse and in colour from clear to yellow or green. The timing can vary from discharge in the morning to continuing throughout the day.

It is often accompanied by other symptoms such as:
• Burning on passing urine
• Frequent need to pass urine
• Excessive need to urinate at night
• Rash in the genital area, which can be painful or itchy
• Swollen lymph nodes in the groin

Causes of penile discharge can be Non-gonococcal or non-specific urethritis and Gonococcal urethritis/ gonorrhoea.

Non-gonococcal or non-specific urethritis (NSU)
NSU is the most common form of penile discharge. Men aged between 20 and 35 years are most commonly affected.
Several different organisms can cause the syndrome:
• Chlamydia trachomatis (25 to 60 per cent).
• Mycoplasma genitalium (up to 25 per cent).
• Ureaplasma urealyticum (15 to 25 per cent).
• Trichomonas vaginalis (17 per cent).
• Herpes simplex (rarely).

Routine tests are not available to detect all of these infections, so the cause of the NSU might not be found.

In some patients, no sexual contact has occurred and the symptoms are blamed on irritants, soaps or detergents. But no firm evidence exists to support this theory.

How diagnosis is made
Penile discharge or urethritis is diagnosed by finding white blood cells on a urethral swab or ‘first catch’ urine sample, for instance by urine taken from when you first begin to pass water. The infecting organism might be identified from these samples.

Ideally, the patient should be seen in an STD clinic for prompt examination of specimens because transfer of specimens to a hospital laboratory can lead to a missed diagnosis.

Other infections are less easily diagnosed. Between six and eleven per cent of sexually active men carry chlamydia in their urethra with minimal or no symptoms.

The development of more sensitive tests, such as polymerase chain reaction and ligase chain reaction, might allow for more precise diagnosis, particularly in patients with no symptoms, and especially if they are sexual contacts of proven infected women. But this is not used routinely in STD clinics.

Treating penile discharge
Treatment depends on the specific organisms. However, national guidelines use syndromic approach that offers broad-spectrum antibiotics, which often cure the problem.

Sexual partners should be given similar treatment. Patients should be followed up after two weeks with repeat swabs (known as ‘test of cure’) because of the high risk of re-infection often due to failure of all sexual partners to comply with therapy.

Contact tracing
It is essential that sexual contacts of men with gonococcal urethritis and NSU are traced and treated, preferably in an STD clinic. Without treatment of sexual contacts, recurrence is likely and treatment will probably fail.