What are those spots on his/my penis?
Men are understandably concerned when they notice spots on the penis. They are frequently worried they may have a sexually transmitted disease or some form of cancer. They may equally be worried about the appearance of their penis and what their sexual partner might think of it.
Spots on the penis are very common and most do not have a serious cause. However, some do and it is important to seek prompt medical advice if you are concerned. This article describes some of the causes of spots on the penis, but reading it and examining your own penis is no substitute for examination by a doctor!
Unless you think that you may have a sexually transmitted disease, the first place to seek advice about spots on the penis is from your doctor. If you are too embarrassed to discuss it with your family doctor or think you might have an STD, go to your local STD clinic.
Spots on the penis can be divided into groups according to their appearance. A brief description will be given of each, its cause and its treatment.
- Ulcers: ulcers appear as craters on the skin and represent a full-thickness loss of skin (epidermis). There is frequently a crust, clear liquid (serum) or pus in the crater.
- Papules: papules are small, less than 1cm diameter, lesions (lumps) raised above the skin surface.
- Plaques: plaques are raised, flat-topped lesions, greater than 1cm in diameter.
Single penile ulcers frequently have a serious cause and it’s important to seek prompt medical advice.
- Primary syphilis: A single, round, painless ulcer on the penis or scrotum is characteristic of the first attack of (or primary) syphilis. It is caused by a spirochaete (spiral-shaped) bacterium called Treponema Pallidum. The diagnosis must be confirmed by laboratory tests. It is an infectious STD.
- Chancroid, granuloma inguinale, lymphogranuloma venereum: These are tropical diseases that cause a single, painless, foul-smelling ulcer. The diagnosis must be confirmed by laboratory tests. They should be suspected in men with a history of sexual contact in tropical areas. They are all infectious STDs.
- Penile cancer (squamous cell carcinoma): May present as a painless, irregular genital ulcer. Early diagnosis and treatment is essential and may be life-saving.
- Multiple penile ulcers are more common and may have a less serious cause. However, seeking prompt medical attention is still very important. They can be divided into two groups, acute – present for less than two weeks and chronic – present for more than two weeks.
Acute ulcers may be caused by:
- Herpes simplex: This is the commonest cause of genital ulceration. It is caused by Herpesvirus hominis type two or sometimes type one – the virus usually associated with oral herpes or cold sores. Herpes is characterized by recurrent bouts of genital vesicles, like small blisters, which rapidly break down to form small, painful ulcers. It is highly infectious and usually sexually transmitted. The first episode is usually associated with an acute feverish illness, which may be quite severe. The diagnosis must be confirmed by laboratory tests. Acute episodes can be effectively treated with antiviral drugs, such as aciclovir, although recurrences are common. Stress or other feverish illnesses may precipitate such recurrences.
- Secondary syphilis: Multiple irregular, shallow, painless, gray ulcers, sometimes described as ‘serpiginous’ like a snail track on the penis, are characteristic of secondary syphilis. It is caused by a spirochaete bacterium called Treponema Pallidum. A flu-like illness and a blotchy, red rash usually accompany it over the body. As with primary syphilis, the diagnosis must be confirmed by laboratory tests. It is an infectious STD.
- Apthous ulcers: These are small, shallow, painful ulcers that most commonly appear in the mouth, but can also affect the penis. Typically they have a gray center surrounded by a bright red halo. They occur in crops and resolve without treatment. They can easily be confused with herpes simplex ulcers so laboratory tests are necessary to reliably distinguish the two. They are not infectious and their cause is unknown.
Chronic ulcers may be caused by:
- Pemphigus: This usually affects other parts of the body, frequently starting in the mouth, but may be restricted to the penis. It appears as fragile, thin-walled blisters, which break down to form ulcers. These are often painful and may itch. There are a variety of different forms, the most severe type may affect the whole body and is life threatening. It is caused by a breakdown in the adhesion between different layers of the skin. Prompt diagnosis and treatment is essential.
- Behçet’s disease: An inflammatory disorder affecting the skin, joints, nerves, eyes and other body systems. It may present with large, deep and painful ulcers on the penis and scrotum, but is always accompanied by mouth ulcers. It is a potentially serious condition and prompt diagnosis and treatment is essential. It’s not infectious.
- Reiter’s syndrome: An inflammatory condition presenting with generalised arthritis. About a quarter of affected men have small, ulcerated plaques around the glans and foreskin. It can also affect muscles, the eyes and nails. It is caused by an abnormal immune response to a gut or genital infection. It may follow a prolonged, relapsing course but can be treated. Reiter’s syndrome is not itself infectious, but the germs that might cause it are. Some of them can be sexually transmitted.
Most penile papules do not have a serious cause, but some are infectious and may lead to more serious conditions. An early penile cancer may also appear as a papule before ulcerating. It is, therefore, important to seek prompt medical advice about penile papules.
- Molluscum contagiosum: A common, benign, infectious viral disease affecting the skin and mucous membranes. It may be sexually transmitted and this is probably the commonest cause of penile molluscum in adult men. It appears as multiple, small, dome-shaped papules, often with a central depression or plug. A curd-like discharge can be squeezed from them. It may disappear without treatment, but freezing or cautery will usually get rid of it. Molluscum contagiosum is a marker for ‘unsafe’ sexual practices and those affected should be screened for HIV.
- Hair follicles and sebaceous (sweat) glands: These are a normal part of the skin’s anatomy and are commonly found on the penile shaft, particularly on the ventral surface (underside). They may be visible as small nodules or might only be felt as small lumps in the skin. They will have a hair arising from them that reveals their true nature. They are quite normal.
- Pearly penile papules: Multiple, small (about 1-3mm) papules running around the circumference of the crown of the glans penis. They typically develop in men aged 20-40, and around 10 per cent of all men are affected. They may be mistaken for warts, are not infectious and require no treatment.
- Fordyce spots: Small (1-5mm), bright red or purple papules that can appear on the glans, shaft or scrotum and usually affect younger men. They may occur as a solitary lesion, but frequently appear in crops of 50-100. They are painless and not itchy, but may cause embarrassment because of their appearance, or a fear that they might be sexually transmitted. They are abnormally dilated blood vessels, covered by thickened skin. They may bleed if injured or even during intercourse. They are not infectious and their cause is unknown. Although a number of approaches have been tried, there is no simple, reliable treatment to remove them. Troublesome, bleeding spots can be electrocauterised.
- Psoriasis: Most commonly affects other parts of the body, particularly the knees, elbows and scalp, but occasionally first appear on the penis, usually on the glans or inner surface of the foreskin. Psoriasis appears as thickened red papules or plaques, with a well-defined edge. In uncircumcised men, and at other sites, it has a scaly surface. It rarely causes irritation. It is caused by an abnormality of skin production and can be inherited. It is unsightly but rarely serious. There are a number of effective treatments available, such as steroid creams and calcipotriol cream.
- Warts: A number of different types of wart may appear on the penis. Genital warts are caused by human papilloma virus (HPV) and are infectious. They may be single or multiple, skin-coloured, pink or brown, with a moist surface. HPV infection is associated with the development of cervical and anal cancer, so it is important that sexual partners are screened for evidence of infection. They can be treated in a variety of ways, from skin paints to cautery, but are sometimes very difficult to eradicate.
Penile plaques do not usually have a serious cause, but some are infectious and others may lead to more serious conditions. Erythroplasia of Queyrat, lichen sclerosis and balanitis xerotica obliterans may lead to the development of penile cancer. It is, therefore, important to seek prompt medical advice about penile plaques.
- Balanitis and posthitis: Balanitis is an inflammatory condition of the glans penis. Posthitis is an inflammatory condition of the foreskin. Symptoms include local irritation, burning and a red rash. Sometimes the skin appears to be peeling off as if scalded. Bacteria and yeasts such as candida can cause it. It’s more common in older men and those with diabetes. Balanitis is infectious and may be sexually transmitted. It can be treated with appropriate antimicrobials.
- Erythroplasia of Queyrat: Appears as a sharply demarcated, bright red plaque, with a velvety surface. It is usually painless and not itchy. It is an early manifestation of penile cancer and needs prompt diagnosis and treatment. Excision of the affected area is usually curative. It is not infectious.
- Zoon’s plasma cell balanitis: Zoon’s balanitis appears as a bright red, shiny-surfaced plaque on the glans or inner surface of the foreskin. It is usually painless but may be accompanied by itching. The cause is unknown. It may respond to application of steroid cream, but frequently recurs. Circumcision is curative, but not essential. It is a harmless condition but can be confused with the much more serious condition of Erythroplasia of Queyrat. It is not infectious.
- Lichen sclerosis and balanitis xerotica obliterans: Lichen sclerosis appears as white plaques on the glans, foreskin or shaft of the penis. It usually has no symptoms, although burning and irritation have been reported. Balanitis xerotica obliterans is a severe form of lichen sclerosis affecting the foreskin of uncircumcised men. The opening or edge of the foreskin is firm and has a white scarred appearance. It is quite inelastic and will not pucker open as it is retracted. This may interfere with passing urine or sex. Both conditions may, rarely, lead to penile cancer and circumcision may be necessary. They are not infectious.
- Psoriasis: See penile papules.
- Eczema: Most commonly affects other parts of the body, but occasionally it may first appear on the penis. In such cases, it may be a skin reaction to an irritant that is better be described as dermatitis. Eczema appears as diffuse, red plaques, with a poorly defined edge and finely scaled surface. It frequently causes quite severe irritation. It can be caused by infection or local reaction to skin injury, from chemicals or radiation. There are a number of effective treatments available, such as steroid creams. It is not infectious.