Male genital dysaesthesia

What is male genital dysaesthesia?

Male genital dysaesthesia is a form of cutaneous dysaesthesia characterised by a burning, hot, irritating discomfort of the penis, foreskin, and/or scrotum. It is often accompanied by increased sensitivity to touch.

Male genital dysaesthesia is also known as dysaesthetic penoscrotodynia (DPSD) or male genital burning syndrome. If dysaesthesia is accompanied by redness, this may be referred to as red scrotum syndrome. Localised symptoms can be described as scrotodynia or burning scrotum syndrome, penodynia, or glansodynia.

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.

Click here for an image of red scrotum syndrome

Who gets male genital dysaesthesia?

Male genital dysaesthesia can affect males of all ages and skin colour. It is more common amongst those with Fitzpatrick type 1 or 2 skin, and those over the age of 50. Data on prevalence are limited.

Genital dysaesthesia associated with redness and vascular hyperreactivity of the scrotum may be associated with rosacea.

What causes male genital dysaesthesia?

While the aetiology of male genital dysaesthesia is not well understood, symptoms may be related to:

• Overactive sensory nerves in affected areas
• Spinal injury and consequent compression of nerve fibres
• Pudendal nerve entrapment
• Local vascular hyperreactivity (from release of vascular activating substances from the nerve endings in the skin)
• Overuse of high-potency topical corticosteroids
• Contact allergy
• Functional somatic symptom disorder
• Localised erythromelalgia.

Alcohol and caffeine may trigger or exacerbate symptoms.

What are the clinical features of male genital dysaesthesia?

Patients experience symptoms including burning, a warm or hot sensation, hyperaesthesia, or irritation of the glans, foreskin, penile shaft, scrotum, or entire external genitalia.

Other symptoms should be explored to assess for other causes of discomfort, such as:

• Itch — 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
• Dysuria and/or penile discharge (symptoms suggestive of sexually transmitted infections or urinary tract infection)
• Sensory or motor loss — enquire about numbness, motor weakness, and sphincter incontinence to exclude possible neurological disease
• Lower back pain
• History of herpes zoster or trauma.

In many patients, no abnormalities are evident on physical examination. Potential clinical findings may include:

• Well-defined erythema of the anterior scrotum, often sparing the median raphe
• Telangiectasia
• Hyperaesthesia eg, tenderness to light touch with a cotton swab.

It has been suggested that male genital dysaesthesia could be classified using a similar system to that introduced for vulvodynia by The International Society for the Study of Vulvovaginal Disease:

• Generalised vs localised
• Provoked vs unprovoked
• Mixed.

How do clinical features vary in differing types of skin?

Erythema may be less apparent in darker skin phototypes.

What are the complications of male genital dysaesthesia?

Patients with genital dysaesthesia may find wearing underwear uncomfortable. Sitting down may exacerbate symptoms. Symptoms may be distressing and affect sleep and/or sexual function.

How is male genital dysaesthesia diagnosed?

Male genital dysaesthesia is a clinical diagnosis.

The following investigations may be indicated to rule out other causes of symptomatology:

• STI tests
• Skin swabs
• Mycology
• Urine dipstick +/- mid-stream urine sample for microscopy, culture, and sensitivities
• Patch tests to exclude allergic contact dermatitis to corticosteroid creams, preservatives, or other products that may have touched the affected area
• Skin biopsy
• Imaging of the back and pelvis (eg, x-ray, CT scan, MRI scan) if there is a history of significant lower back pain, trauma, or surgery.

What is the differential diagnosis for male genital dysaesthesia?

• Tinea cruris
• Bacterial infections
• Sexually transmissible infections
• Balanitis
• Contact dermatitis
• Atopic dermatitis
• Lichen sclerosus.

See also: Genital skin problems.

What is the treatment for male genital dysaesthesia?

Treatment of male genital dysaesthesia can be challenging and symptoms can be persistent. The following measures may be helpful.

General measures

• Patient support and education.
• Stop using antiseptic or antibacterial wipes, washes, or deodorants in the genital area.
• Use soap-free cleansers in the bath/shower.
• Moisturise with bland, non-irritating emollients after bathing/showering.
• Wear loose-fitting, cool underwear (eg, boxer shorts).
• Stop using topical corticosteroid cream on the genital region.
• 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.
• Avoiding caffeine or alcohol may alleviate symptoms.
• Psychological therapy and pain management therapy; referral to a pain specialist may be helpful in some cases.

Specific measures

Topical preparations:

• Menthol 1% in aqueous cream applied PRN / up to 3–4 times daily to cool affected areas; may be difficult to tolerate
• Pimecrolimus cream applied 1–2 times daily may reduce redness and burning
• Tacrolimus 0.1% ointment.

Systemic treatments:

• Doxycycline
• Amitriptyline or nortriptyline – often effective for neuropathic pain; can be sedating and cause anticholinergic side-effects
• Gabapentin, pregabalin, or sodium valproate – may also alleviate neuropathic pain
• Beta-blockers: low-dose oral carvedilol and 0.5% timolol gel have been found to improve symptoms after 2 weeks of use
• Serotonin-noradrenaline reuptake inhibitors (eg, duloxetine, venlafaxine).

Other potential treatments reported to be effective for idiopathic scrotal dysaesthesia:

• Ivermectin (oral or topical)
• A recent case report (Raef et al, 2021) found intradermal botulinum toxin effective for a patient with a 2-year history of scrotal dysaesthesia refractory to other therapies including pregabalin, gabapentin, and duloxetine.

How do you prevent male genital dysaesthesia?

As the aetiology of male genital dysesthesia is unknown, preventative strategies are unclear.

What is the outcome for male genital dysaesthesia?

Male genital dysaesthesia may spontaneously resolve or can be a chronic condition. The aim of treatment is to reduce symptom severity and improve quality of life.