Male genital dysaesthesia

What is male genital dysaesthesia?

Male genital dysaesthesia is a form of cutaneous dysaesthesia and describes a sensation of burning, heat, irritation, discomfort or increased sensitivity to touch of the penis, foreskin or scrotum. Some men with genital dysaesthesia also find wearing underpants or sitting down difficult. Symptoms may be very stressful and interrupt sexual function and/or sleep. The affected areas may appear redder than normal.

Genital dysaesthesia does not usually result in itch (the desire to scratch). If itch co-exists with genital dysaesthesia, it may be explained by the development of irritant contact dermatitis due to various applications to the affected area including soap and creams.

Other names for male genital dysaesthesia include:

• The burning scrotum syndrome
• Peno-scroto-dynia (pain of penis and scrotum) or scrotodynia, in which there is no redness.
• The red scrotum syndrome, in which genital dysaesthesia is accompanied by redness.

Both men and women with genital dysaesthesia may experience similar symptoms of burning, irritability or discomfort of their genital region. In women these symptoms are often called vulvodynia, which describes vulval pain in the absence of primary rash.

Which men get genital dysaesthesia?

Most men with genital dysaesthesia are over 60 years of age, fair-skinned and of Caucasian descent (“European”). However, genital dysaesthesia sometimes affects younger or darker-skinned men. They are usually otherwise healthy.

Genital dysaesthesia associated with redness and vascular hyper-reactivity of the scrotum may be associated with rosacea, a common disorder in which facial flushing leads to persistent facial redness.

What are the findings on examination?

In many men with genital dysaesthesia, the affected areas appear entirely normal on careful examination. However, findings sometimes include:

• Red skin, particularly of the scrotum, often with sharp borders
• Broken blood vessels (telangiectasia)
• Extreme tenderness
• Sensation of pain when lightly touched e.g. with cotton swab (hyperaesthesia or hyperalgesia)

What is the cause of genital dysaesthesia?

The cause or causes of genital dysaesthesia are often difficult to pinpoint.

• The sensations are due to overactive nerves in the affected skin.
• Symptoms due to compression of nerve fibres on their pathway from the spinal cord may be similar, for example pudendal nerve entrapment. In this case other symptoms such as urinary symptoms or disorders of sexual function may occur.
• Redness is caused by vascular hyper-reactivity, perhaps due to release of vascular activating substances from the nerve endings in the skin.
• Redness may also arise as a consequence of long-term application of strong corticosteroid creams to genital tissue; on the face, this is called steroid rosacea.
• Genital dysaesthesia may be a similar condition to erythromelalgia, a disorder in which there is burning and redness affecting the feet, or less frequently, the hands.

Chronic genital dysaesthesia is not caused by cancer. But to make sure this is the case, the affected skin, the prostate and the spine should be carefully examined.

Genital dysaesthesia is not due to infection. However, blood tests and skin swabs may be arranged to exclude sexually transmissible diseases (STD), eg genital herpes, which might cause rather similar symptoms.

Factors contributing to genital dysaesthesia may include:

• Genetic tendency
• Back injury or spinal disease
• Over-use of strong topical corticosteroid creams.

Are special tests or investigations needed?

When symptoms and signs are typical, an experienced doctor may make the diagnosis of genital dysaesthesia without requiring special tests. However sometimes the following investigations are arranged.

• Patch tests to exclude allergic contact dermatitis to corticosteroid cream, preservative or other product that may have touched the affected area. Results are usually negative in genital dysaesthesia.
• Imaging of the back and pelvis (eg X-ray, CT scan, MRI scan)
• Examination of the prostate (PSA blood test, digital examination)

How is male genital dysaesthesia treated?

Many men are relieved to have their symptoms explained when given the diagnosis of male genital dysaesthesia.

Many treatments may have already been tried before the correct diagnosis is made. Unfortunately, no treatment works all the time, every time.

General measures for an oversensitive genital area may include:

• Replace soap with non-soap cleanser.
• Wear loose-fitting, cool underwear (e.g. boxer shorts).
• Don’t use antiseptic washes, wipes or deodorants in the genital region (penis, scrotum) or around the anus.
• Apply low-irritancy moisturising cream after showering to the genital region and whole body (e.g. non-ionic cream or sorbolene cream)
• Stop all other creams, especially corticosteroid creams; steroid creams are prescribed for dermatitis/eczema, and they are usually effective for this within a few days. They are ineffective for genital dysaesthesia, and when used for prolonged periods they may make redness and burning sensation worse.
• Cold compresses may be temporarily soothing, such as a face flannel moistened with cool or cold water and placed on the penis and/or scrotum.

Specific prescription treatments reported to be of benefit include:

• 1% Menthol in aqueous cream applied 3 to 4 times daily to cool affected areas. Although sometimes helpful, it can also be difficult to tolerate.
• Pimecrolimus cream may be used 1 to 2 times per day for genital dermatitis. It has been reported to reduce redness and burning in some men with genital dysaesthesia.
• Doxycycline 50 mg tablets once or twice daily for 3 to 6 months to reduce redness; this tetracycline antibiotic is particularly effective if symptoms have been provoked by strong corticosteroid creams but it may also help burning and redness of unknown cause.
• Tricyclic medication at teatime or bedtime, e.g. amitriptyline or nortriptyline 5-30mg, is used to counteract the irritable nerves that cause the burning sensation. Start with a low dose and build up slowly to reduce risks of drowsiness.
  Do not take amitriptyline if you are going to drink alcohol, drive a car or operate dangerous machinery. If you are drowsy in the morning, reduce or stop your amitriptyline or try taking amitriptyline earlier in the evening.
  Tricyclics may cause dry mouth, dizziness or constipation. Most men tolerate low-dose amitriptyline extremely well, with improvement of their genital dysaesthesia. If it causes daytime drowsiness, stop the medication.
• Anticonvulsant agents such as gabapentin, pregabalin or sodium valproate are medications often used for neuropathic pain syndromes. They can be very effective in male genital dysaesthesia.
• The beta blocker carvedilol has been reported in low dose to result in resolution and long-term remission of the red scrotum syndrome.

Long-term outlook for men with genital dysaesthesia

Male genital dysaesthesia is a frustrating disease to live with, and can be very persistent. It can result in great distress, embarrassment and fear. Many treatments have often been recommended and tried with limited or no success. Yet sometimes, it settles down and completely resolves in time.

Medical science continues to look for better treatments.