What Is an Angiokeratoma?

Medically Reviewed by Stephanie S. Gardner, MD on April 26, 2022
Written by Alyssa Anderson
4 min read

An angiokeratoma is a skin lesion or wound. It's created when an open capillary ⁠— a type of blood vessel ⁠— in a lower layer of your skin gets covered with extra layers of skin cells. This can make them rough and bumpy.

There are a few types of angiokeratomas - Fordyce, Mibelli, and those associated with Fabry disease.

Angiokeratomas aren't harmful or contagious. Their symptoms are mild. Sometimes they'll bleed when they're scratched or otherwise hurt. They're most often seen in older people, but may also be caused by a genetic condition.

Angiokeratomas are almost always less than a centimeter in size. They can appear as individual spots or as clusters. Their colors range from dark red to bluish. They can also be hard or scaly when you touch them, and can look like a wart. 

The darkness and hardness are caused by blood — from the open capillary — that has pooled beneath the skin's surface. The scaly texture is caused by the extra skin cells. 

An angiokeratoma can appear in several locations on your body, including your scrotum, vulva, knees, elbow, and torso. Pay attention to where you notice your angiokeratomas — the location can help you figure out what's causing your lesions.

Unless there's an underlying genetic condition, many doctors believe that angiokeratomas are caused by past damage to the skin at that particular location.

Angiokeratomas are not a symptom of a sexually transmitted disease (STD). This is a common misconception, because an angiokeratoma of Fordyce causes lesions in the genital areas. 

Angiokeratoma of Fordyce causes many ⁠— up to hundreds ⁠— of skin lesions on either your scrotum or vulva. This condition is most common in older people.

This type of angiokeratoma is seen more often on scrotums than vulvas. On scrotums, the lesions usually don't have any symptoms and shouldn't affect your daily life.

Angiokeratoma of Fordyce can be much more painful when it's located on the vulva. These lesions likely won't have any irritating symptoms when they first form, but over time, they can become itchy and painful. You should talk to your doctor if you begin to feel any irritation from your angiokeratomas.

Angiokeratoma of Mibelli is an inherited condition. These lesions are caused by a dominant gene mutation, which means that if one of your parents has the disease, there's at least a 50% chance that you'll also have the disease. 

With this particular kind of angiokeratoma, you’ll typically develop lesions on your knees, elbows, and the back of your hands.

Also caused by a genetic condition, angiokeratomas from Fabry disease are much rarer. These lesions are typically located on your torso and look like a lot of small red dots.

Fabry disease can lead to organ damage. The appearance and location of these angiokeratomas can be a helpful tool in diagnosing this serious condition.

The mutation that causes Fabry disease is recessive and on the X chromosome. This means that males ⁠— who only have one copy of the X chromosome ⁠— need to inherit the disease from their mothers. Females need to get two copies of the mutation ⁠— one from each of their parents.

Another rare type, angiokeratoma circumscriptum lesions form on the legs and look very similar to melanomas ⁠— a type of skin cancer. While very few cases have been reported, your doctor should consider this type of angiokeratoma when diagnosing your skin condition ⁠— as an alternative to cancer.

Angiokeratomas can last on your skin for a long time. Usually, angiokeratoma symptoms are very mild. You should not feel any discomfort or other symptoms most of the time.

If your lesions are bleeding a lot or have become painful, talk to your doctor about treatment options. Your doctor may try to scrape or freeze off these lesions. These procedures are considered safe and easy and are done in the doctor’s office. 

Some angiokeratomas ⁠— like those caused by Fordyce⁠ — can be treated with pulsed dye laser surgery. In this procedure, a laser is used to treat the blood vessels that cause the lesions. There's also some evidence that a topical rapamycin cream can help. Talk to your doctor to see if either of these treatments is right for you. 

Due to their appearance, all angiokeratomas can sometimes be mistaken for skin cancer. Your doctor should examine them just to make sure that you have an angiokeratoma and not a cancerous tumor.