Chronic Actinic Dermatitis - Causes, Symptoms, and Treatment

Introduction

Chronic actinic dermatitis (CAD) is an immune-mediated photodermatosis condition. Chronic actinic dermatitis (CAD) is characterized by pruritus and eczema. The lichenified plaques are found mostly on sun-exposed areas with significant sparing of symptoms, including eyelids, skin folds, and skin behind the ear region. Chronic actinic dermatitis is a skin reaction due to secondary skin photosensitization. The condition arises in the endogenous antigen present in the skin. Management of chronic actinic dermatitis should contain photoprotection. Topical agents, such as corticosteroids and calcineurin inhibitors, are effective. Other treatment measures include oral Prednisone, Azathioprine, Cyclosporine, and Mycophenolate mofetil. If identified, photoprotection and avoidance of allergens are done to improve the symptoms.

What Is Chronic Actinic Dermatitis?

Chronic actinic dermatitis is a rare skin condition, and it is more susceptible in men over the age of 50 years. Middle-aged or older people are mostly affected by this skin condition. Chronic actinic dermatitis symptoms are severe itching, erythema or redness, inflammation, and thick and dry skin. The symptoms are specifically observed in regions exposed to sunlight or artificial light. Chronic actinic dermatitis is also known as chronic photosensitivity dermatitis and actinic reticuloid. Actinic reticuloid comes from the histological findings of skin biopsies of T-cell lymphoma. People who have a history of another dermatitis, such as atopic dermatitis, allergic contact dermatitis owing to plants, or photo contact dermatitis for many years before the photosensitivity develops, are predisposed to chronic actinic dermatitis. In such cases, chronic actinic dermatitis is sometimes referred to as a persistent light reaction. Chronic actinic dermatitis has several names. The numerous names offered by various scientists are listed below.

• Chronic actinic dermatitis (CAD) is the term first introduced in 1979 by Hawk and Magnus.

• Wilkinson described persistent light reactivity in 1961.

• Actinic reticuloid was described by Ive et al. in 1969.

• Ramsay and Black described photosensitive eczema in 1973.

• Photosensitivity dermatitis was described by Frain-Bell et al. in 1974.

What Are the Causes of Chronic Actinic Dermatitis?

Chronic actinic dermatitis has been noted in Caucasians, Latin Americans, Japanese, Blacks, and Indians and is most typical in temperate climates. The condition is typically seen in older adults and rarely involves women. Chronic actinic dermatitis may appear after endogenous eczema. Chronic actinic dermatitis can also be seen in people with a history of some skin condition. Some of the causes of chronic actinic dermatitis are given below.

• Excessive sun exposure.

• Minimal erythema dose to UVA (ultraviolet A), UVB (ultraviolet B), and visible light.

• Endogenous eczema.

• Photoallergic dermatitis.

• Allergic contact dermatitis.

• Oral drug photosensitivity.

• Occasionally polymorphic light eruption.

• Rarely human immunodeficiency virus infection.

What Are the Symptoms of Chronic Actinic Dermatitis?

The initial symptom of chronic actinic dermatitis usually appears with persistent erythema or redness of the face. Chronic actinic dermatitis has various symptoms and is typically present in the face, scalp, V-area of the chest, back and sides of the neck, and dorsal aspects of hands and forearms. The skin features of chronic actinic dermatitis are observed in the sharp demarcated lines of the skin or folded areas. Some of the symptoms of chronic dermatitis are mentioned below.

• Eczema.

• Erythema.

• Pruritus.

• Lichenified eruptions in the skin.

• Thick and dry skin.

• Palmar and plantar eczema.

• Loss of eyebrow.

• Scalp hair loss.

• Skin scratching causes erythroderma.

• Blisters.

• Desquamated skin.

How to Diagnose Chronic Actinic Dermatitis?

The diagnosis is based on the history of sun exposure and physical examination. Since chronic actinic dermatitis is a photosensitivity dermatitis condition that arises due to ultraviolet and often visible irradiation, a positive result is obtained in the photo patch testing. Various diagnostic tools diagnose chronic actinic dermatitis. Some of the diagnostic measures for diagnosing chronic actinic dermatitis are mentioned below.

• History of sun exposure.

• History of symptoms.

• Physical examination.

• Photo tests.

• Complete blood count.

• Photopatch testing.

• Immunohistochemistry includes antinuclear antibodies, anti-Ro, and anti-La antibodies.

• Histological examinations.

The histological features of chronic actinic dermatitis are mentioned below.

• Epidermal spongiosis.

• Mild acanthosis.

• Hyperplasia.

• Focal parakeratosis.

• Necrotic keratinocytes.

• Spongiotic epidermis.

• Exocytosis of lymphocytes.

• Inflammatory infiltration.

• Mononuclear-cell infiltration.

• Large hyperchromatic convoluted nuclei are present.

• Mitotic figures are present.

• Macrophages contain melanin.

• Eosinophils and plasma cells are present.

• CD8 cells in the epidermis are predominant.

What Is the Treatment for Chronic Actinic Dermatitis?

The treatment is mainly done with sunlight avoidance and allergen avoidance. Sunlight avoidance includes:

• Wearing protective clothing.

• Applying non-irritating broad-spectrum sunscreens.

• Applying filters to home and car windows.

Medical Therapy:

• Topical and oral glucocorticoids with emollients are usually essential. Topical Tacrolimus ointment is beneficial.

• Treatments for resistant disease include low-dose PUVA (Psoralens and ultraviolet radiation) and photochemotherapy.

• Narrow-band UVB phototherapy.

• Cyclosporine.

• Azathioprine.

• Mycophenolate mofetil alone or in combination.

Skin preventive measures for sun exposure are mentioned below.

• Always use a broad-spectrum sunscreen with a sun protection factor or SPF applied before an hour of sun exposure.

• Water-resistant sunscreen products should be used.

• Protect the children with long sleeves and long pants. In addition, lightweight cotton clothing and sun protection factor-rated clothing and hats are advisable.

• Keep the children in the shade as much as possible.

• Beach umbrellas and other similar objects provide shade.

• A hat with a wide brim is advised.

• Cool the skin with a cool shower.

• Drink plenty of water.

• Allow adequate healing for sunburnt skin.

• Avoid tight clothes.

• Applying ice packs or petroleum jelly to the affected area should be avoided.

• Scratching or peeling burnt skin is also strictly avoided.

Conclusion

Chronic actinic dermatitis, also known as photosensitivity dermatitis and actinic reticuloid syndrome, presents as dermatitis and a pseudolymphomatous eruption. Abnormal photosensitivity reaction of the skin to ultraviolet (UV) and often visible radiation is the causative pathogenesis of chronic actinic dermatitis. Histopathologic features vary, ranging from mild dermatitis to pseudolymphomatous features. Photo testing and patch testing are the actual tests to diagnose and advise avoidance of the sun and other responsible wavelengths and any contact allergens. The treatment recommended is sunlight and allergen avoidance, in addition to topical corticosteroids and emollients. In severe cases, systemic Prednisolone or Azathioprine is considered to improve the symptoms and avoid the risk.