What is Actinic Prurigo & How is it Treated?

What is Actinic Prurigo?

Actinic Prurigo is a condition characterized by episodes of severe itching in areas of the body exposed to direct sunlight. Primarily, Actinic Prurigo causes rashes that are extremely itchy. It also causes small erythematous papules on the skin surface. These papules may crust or ooze at times. The most common area where it can be seen is the face, lips, cheek, neck, arms, and chest. Sometimes, Actinic Prurigo may also cause severe irritation in the eyes, especially in hot weather conditions.[1,2,3]

There have also been cases of Actinic Prurigo where body parts that have not been exposed to sun have also been affected. Actinic Prurigo is seen mainly in females and that too girls who are about 10 years of age even though anyone can get it at any age. There is a strong genetic link to the development of Actinic Prurigo. It is mainly seen in people living in Central, North, and South America.[1,2,3]

There is no cure for Actinic Prurigo but symptoms can be managed. The management begins with maximum avoidance of direct sun. If that is not possible then proper care should be taken to protect the body parts that are exposed directly to sun. Additionally, topical corticosteroids and anti-itch creams are also quite effective for flare-ups of Actinic Prurigo.[1,2,3]

What Causes Actinic Prurigo?

The primary cause of Actinic Prurigo is not very clear. However, experts believe there is a strong genetic link to the development of this condition pointing it towards being an autoimmune disorder. Actinic Prurigo is extremely rare in the United States but is seen commonly in the South and Central American nations due to the intensity of the heat in these regions.[1,2]

There is no gender bias for Actinic Prurigo but is seen more in females than males. It can develop at any age but usually is seen in girls around 10 years of age. Some studies mention that Actinic Prurigo is seen more in dry and warm climatic conditions.[1,2]

What are the Symptoms of Actinic Prurigo?

The symptom onset of Actinic Prurigo is begins generally in the spring as the intensity of sunlight increases by then and people spend more time out in the sun after the tough winter. The primary presenting symptom of a person with Actinic Prurigo is severe itchy erythematous rash in the area exposed to the sun like the face, neck, cheeks, and arms.[1,2]

In some cases, even the unexposed areas of the body may get the classic rash as seen with Actinic Prurigo. There may also be thickening of the skin and scarring. Another telltale sign of Actinic Prurigo is the presence of actinic cheilitis. This is a condition characterized by inflammation of the lip after excessive sunlight exposure. In fact, this may be the only sign present in a patient with Actinic Prurigo.[1,2]

How is Actinic Prurigo Treated?

Mild cases of Actinic Prurigo can be easily managed by avoiding sun exposure. If the person has to go out in the sun then protecting the parts of the body exposed to sun by way of sunscreen and sunglasses, wearing protective clothing, and going into shade as much as possible is recommended. Wearing wide-brim hats is also quite effective in avoiding direct sunlight on the face.[1,2]

For more severe cases, topical corticosteroids and antihistamines have been shown to be effective in managing the symptoms of Actinic Prurigo. For more chronic and severe cases, the patient will require aggressive treatments in the form of antimalarials, tetracyclines, and systemic steroids. Thalidomide has shown excellent effectiveness in the treatment of Actinic Prurigo when other medications have been proved to be ineffective.[1,2]

However, this treatment approach has a side effect profile which includes peripheral neuropathy and teratogenicity, both of which are major side effects and caution needs to be maintained while taking this medication. Additionally, this treatment is not recommended for pregnant females or females who are trying to conceive. Females of reproductive age are recommended to use contraceptives while on the thalidomide therapy for treatment of Actinic Prurigo. People on this therapy should be closely monitored for any signs of peripheral neuropathy.[1,2]

Alternatively, immunosuppressive agents like cyclosporine have also been found to be beneficial in managing the symptoms of Actinic Prurigo. Another treatment that has been extremely successful in treating the skin changes caused by Actinic Prurigo is Photochemotherapy.[1,2]

In conclusion, Actinic Prurigo is a condition that tends to recur every time the body is exposed to direct sunlight. There is no known cause for this condition. Minor cases of Actinic Prurigo can be treated with just sun avoidance. However, chronic and refractory forms will require treatment with immunosuppressants like cyclosporine and thalidomide.[1,2,3]

Caution needs to be maintained when being on thalidomide therapy as it has significant side effect profile of peripheral neuropathy for which the patient should be closely monitored. It is also recommended that pregnant females not use this medication and females of reproducing age use contraceptives when on this medication.[1,2,3]

It has also been seen that some people especially girls who have not attained puberty outgrow this condition and by the time they become adults there is complete resolution of Actinic Prurigo.[1,2,3]

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