Angiokeratoma of Fordyce is caused by the dilation of small blood vessels in the upper layer of skin on the scrotum or vulva, combined with a thickening of the skin above them. The exact trigger for this process isn’t fully understood, but increased venous pressure in the genital area is the leading theory. These lesions are benign, becoming more common with age, and pose no risk of turning cancerous.
The Role of Venous Pressure
The most widely discussed explanation centers on elevated blood pressure within the veins of the genital region. When pressure builds in the small capillaries near the skin’s surface, they can stretch and widen permanently. Over time, the skin covering these dilated vessels thickens and becomes rough or scaly, producing the characteristic dark red or purple bumps.
Several conditions that raise local venous pressure have been found alongside angiokeratomas. These include varicocele (enlarged veins in the scrotum), inguinal hernias, tumors of the epididymis or urinary tract, prior trauma, and blood clots in nearby veins. One clinical series found that up to half of patients with scrotal angiokeratomas had an associated condition that could increase venous pressure. In one case, treating a varicocele led to the angiokeratomas resolving entirely.
The Debate Over Venous Pressure
Not everyone in dermatology agrees that venous pressure is the primary driver. A study of 435 military recruits aged 18 to 19 found that 10% had varicoceles, yet none had angiokeratomas. The same researchers surveyed 30 soldiers aged 45 to 55 with varicoceles and again found no angiokeratomas. A separate study of 1,552 Japanese males found no history of any venous obstructive disorders among those with the condition. Many cases appear in people with no identifiable cause for increased venous pressure at all.
So while venous pressure likely plays a role in some cases, it clearly doesn’t explain every one. The formation of these lesions is probably influenced by multiple factors, including aging itself, which naturally weakens blood vessel walls and thins the skin.
Age and Who Gets Them
Angiokeratoma of Fordyce is rarely seen in children. It overwhelmingly affects adults, becoming increasingly common in middle age and beyond. The condition is more frequently reported in men (on the scrotum) but also occurs in women (on the vulva). The age-related pattern supports the idea that gradual wear on blood vessel walls, combined with years of low-grade venous pressure changes, contributes to their development.
What They Look and Feel Like
The lesions appear as small, dark red to purple or even black papules on the scrotal or vulvar skin. They typically measure a few millimeters across. Some people have just a handful; others develop dozens. The surface often has a slightly rough or warty texture due to the thickened skin overlying the dilated blood vessels.
Most of the time, angiokeratomas cause no symptoms. Some people experience itching or a burning sensation. One notable characteristic is that the lesions can bleed easily, even from minor contact like toweling off after a shower or friction from clothing. This bleeding is often what prompts someone to notice them and seek evaluation.
Ruling Out Fabry Disease
One important reason to get angiokeratomas evaluated is to distinguish the harmless Fordyce type from angiokeratoma corporis diffusum, which is linked to Fabry disease. Fabry disease is a genetic condition where the body can’t properly break down certain fats, leading to progressive damage to the kidneys, heart, and nervous system. About 66% of men and 36% of women with Fabry disease develop angiokeratomas.
The key difference is distribution. Fordyce angiokeratomas stay confined to the genitals. In Fabry disease, lesions spread across a wider area, commonly the buttocks, thighs, and lower trunk, in what’s described as a “bathing trunk” pattern. Fabry disease also produces other symptoms like burning pain in the hands and feet, reduced sweating, and kidney problems. If angiokeratomas appear outside the genital area or are accompanied by other unexplained symptoms, testing for Fabry disease is warranted.
Treatment Options
Because angiokeratoma of Fordyce is benign, treatment is only necessary if the lesions bleed frequently, cause discomfort, or create cosmetic concern. Several approaches work well.
Laser therapy is the most studied option. Pulsed dye lasers have shown good to excellent results in clinical studies, with transient bruising and minimal bleeding as the only side effects. In one study of 24 patients, treatment took between one and seven sessions, and only four experienced recurrence. Other laser types have also performed well, with some patients seeing full resolution after a single treatment and others needing a few sessions spaced weeks apart. Recovery after laser treatment is generally quick, with results visible within a few weeks.
Electrocautery uses a small electrical current to destroy the lesions and works well for more widespread cases. It can be done with or without local numbing. Cryotherapy, which freezes the lesions with liquid nitrogen, is another option, though it carries a higher risk of leaving lighter patches of skin or minor scarring. For someone with only a few lesions, simple surgical removal under local anesthesia produces good cosmetic results. Sclerotherapy, where a solution is injected directly into the lesion to collapse the dilated vessels, has also been used successfully with minimal side effects.
Regardless of the method, recurrence is possible since the underlying tendency for blood vessels to dilate in the area doesn’t change. New lesions may develop over time even after successful treatment of existing ones.