What is Actinic Purpura?
Actinic purpura is a harmless condition that affects the skin’s connective tissues due to long-term exposure to the sun. First described by Bateman in 1818, it’s also known as Bateman’s senile purpura or Bateman’s disease. This condition usually affects elderly people, causing dark purple patches on areas of the skin that have been exposed to the sun, particularly on the backs of the hands and on the forearms. These patches typically fade over the course of up to three weeks. While some might use the term ‘solar purpura’ interchangeably with ‘actinic purpura,’ it’s best to use ‘solar purpura’ when referring to purple spots that appear suddenly after sun exposure.
What Causes Actinic Purpura?
Actinic purpura is a skin condition caused by long-term exposure to the sun, which leads to skin thinning due to the harmful ultraviolet rays. This exposure weakens the skin’s connective tissue, making it unable to properly support the small blood vessels within the skin. As a result, even minor injuries that often go unnoticed can cause blood to leak into the skin layers.
This is one of the symptoms of a condition called dermatoporosis, which is marked by skin fragility, thinning of the skin, and the appearance of irregular scar-like patterns on the skin.
Risk Factors and Frequency for Actinic Purpura
Actinic purpura is a condition often found in older people, particularly those with light skin who are more sun-sensitive. The likelihood of having this condition increases with age and how much they have been exposed to ultraviolet light. Roughly 12% of people over the age of 50 and up to 30% of people over 75 are estimated to have it. This condition tends to affect both males and females equally.
Signs and Symptoms of Actinic Purpura
Actinic purpura is a skin condition that shows up as irregular, uneven patches and spots on the forearm and back of the hands. However, it can appear on other parts of the body too, like the legs, neck, and face. These spots usually look like dark purple patches and bruises, measuring around 1 to 4 centimeters in diameter. They usually don’t cause discomfort or itching. The skin around these spots may look thin, pigmented, and lack elasticity.
Other signs of skin damage due to aging and sun exposure, such as wrinkles, brown spots, a sallow yellow skin tone, and other similar skin lesions, like actinic keratosis and stellate pseudo scars, might also be visible alongside actinic purpura.
- Iregular patches and spots on the forearm and back of the hands
- Can also appear on legs, neck, and face
- Dark purple patches and bruises
- No discomfort or itching
- The skin around these spots may look thin, pigmented, and lack elasticity
- Possible presence of wrinkles, brown spots, a sallow yellow skin tone, and others like actinic keratosis and stellate pseudo scars
These purpura, or bruise-like spots, usually stay on the skin for about one to three weeks before fading away on their own. It’s important to note that they don’t show the usual signs of skin inflammation. Occasionally, a brown pigmentation may be left behind due to residual hemosiderin, a type of iron-storage complex, in the skin. Because the skin and blood vessels have already been compromised, actinic purpura can keep occurring. The appearance of these spots could be a cosmetic concern and might impact individuals psychologically, but they don’t pose any serious health risk.
Testing for Actinic Purpura
Actinic purpura, a skin condition, is typically diagnosed based on a person’s medical history and a physical examination by a healthcare professional. In some rare cases, a skin biopsy might be performed for further analysis. This involves looking at a small sample of skin under a microscope.
If this is done, the skin may appear thinner with fewer collagen fibers (which provide strength and flexibility) and abnormal elastic fibers. The walls of the blood vessels in the skin would look normal, but there may be leaking red blood cells and iron storage compound (hemosiderin) deposits marked by a special type of staining called Perl’s staining.
In about 10% of cases, there may be an increase in a type of white blood cell called neutrophils. This could lead to misunderstanding the condition as another skin disorder like neutrophilic dermatosis or leukocytoclastic vasculitis.
Blood clotting tests are rarely needed for this condition and usually show normal results.
Treatment Options for Actinic Purpura
Actinic purpura, a harmless condition, doesn’t typically require specific treatment as new spots continue to appear throughout a person’s life. The best approach is prevention, which includes protecting the skin from too much sun exposure. This can be achieved by putting on sunscreen with a high protection level (a sun protection factor, or SPF, above 50) daily. This will provide ample protection against harmful ultraviolet rays. It’s recommended to apply the sunscreen liberally to all areas of skin that will be exposed to the sun.
When it comes to treating actinic purpura spots that have already formed, the options are limited. Tretinoin, a product made from vitamin A, could theoretically help to reverse severe skin damage caused by ultraviolet light, as it is known to aid skin regeneration and reduce the amount of abnormal elastin, a protein in the skin that can be damaged by sun exposure. However, some studies suggest that the spots caused by actinic purpura do not improve with tretinoin treatment.
Interestingly, in 2002, there was a successful case of using engineered skin to treat actinic purpura in a patient, though this has not been repeated since. More recently, it has been found that a substance called the human epidermal growth factor may be an effective treatment for actinic purpura. It seems to increase skin thickness and decrease the number of purpura spots when used twice daily for a six-week period. A blend of compounds called bioflavonoids, which are found in citrus fruits, has also been tested as a treatment for actinic purpura. After a six-week trial, the group using the bioflavonoids experienced a 50% reduction in purpura spots, with no reported side effects.
Laser therapy, often used to treat aging skin, is not suitable for actinic purpura. Moisturizing creams, however, may help alleviate associated dry skin.
What else can Actinic Purpura be?
When trying to determine if someone has Actinic purpura, a condition characterized by purple spots on the skin caused by sun exposure, doctors might also consider other conditions that can cause similar symptoms:
- Purpura caused by steroid use
- Purpura caused by physical injury
- Purpura caused by the use of blood-thinning medications
- Scurvy, a disease caused by a lack of Vitamin C
- Vitamin K deficiency
- Psychogenic purpura, which is purpura caused by psychological stress or trauma
- Palpable purpura, which is purpura that can be felt and is caused by bleeding and inflammation
- Primary systemic Amyloidosis, a rare disease that can lead to purpura
The doctor would then rule out these possible conditions by conducting necessary tests and investigations.
What to expect with Actinic Purpura
The disease generally has a favorable outcome with a mild progression. Skin lesions commonly appear throughout a person’s life, but typically, they heal in one to three weeks. After healing, one might notice an increase in skin pigmentation or some scarring. However, these outcomes lead to no other major complications.
Possible Complications When Diagnosed with Actinic Purpura
This is a harmless condition that typically clears up in 1 to 3 weeks, though there may be some leftover discoloration or potential scarring. These skin changes could cause emotional distress for the patient, due to changes in their appearance.
