Diagnostics and Treatment of photodermatosis

Photodermatosis – skin diseases, that occur due to exposure to ultraviolet A and B light.

The most common photodermatosis are:

• polymorphic light dermatosis;
• photoxic dermatitis;
• photoallergic dermatitis;
• sunlight heves and other diseases.

How to diagnose photodermatosis?

Anamnesis and clinical picture are the most important for diagnostics of photodermatosis. The diagnose may be confirmed using phototests, lab tests and dermal biopsy. A minimal erythemic dose is determined,i.e. dermal sensitivity to ultraviolet light. When minimal erythemic dose is determined a skin is exposed to UVA and UVB in geometrically increasing doses. This test is evaluated immediatelly and in 24 hours. Photoprovocative tests are performed when polymorphic light dermatosis, sunlight hives, actinic prurigo of chronic actinic dermatitis are suspected. Photopatch test is performed to diagnose photoallergic dermatitis.

Polymorphic light dermatosis

What is “polymorphic light dermatosis” ?

It is the most common photodermatosis that typically appears as rashes in the skin regions that are exposed to sunlight. This disease is miscalled „sun allergy“. Rashes appear in several hours following exposure to the sunlight, but may appear in several days. Usually it happens in spring during March – June period.

What is “polymorphic” skin lesions?

They are very different. Exanthema may manifest as spots, nodules, plaques, blisters. But usally elements of exanthema are one kind of skin lesions, for example ,only nodules.

Who is ill with polymorphic photodermatosis?

Everybody may have this desease, but women has it 9 times more frequently than men and children.

How is treated polymorphic photodermatosis?

Avoidance of sunlight and use of protective suncreams is enought for the patient to prevent any rashe. In case of disease a dermatologist consultation is required and she / he will administer you a proper treatment . Phototherapy – prophylactic treatment using UVA or UVB rays is used. Phototherapy is performed 1.5-2 months before the season of shedulled vacations. In this way the skin is wean on sunlight. UV light procedures are performed to the patient 3-4 times a week. The average duration of the treatment is 5 weeks.

Sunlight hives

What is “sunlight hives” ?

This is a real ”sunlight allergy“. This is a rare disease. Red spots , wheals and urtica appear immediatelly following exposition to sunlight. Skin reaction commonly occurs in the regions exposed to sunlight, but also may appear in the regions not exposed to sunlight.

Who has sunlight hives?

Women has more commonly than men. The disease may manifest at any age, commonly before 40 years.

Why somebody has sunlight hives?

A mechanism of development of disease is still unclear. It is supposed, that UV light triggers fast-type allergic reaction.

How sunlight hives are treated?

Phototherapy is performed 3-4 weeks before season or shedulled vacations. The treatment is performed using UVA, UVB or PUVA. In such way a skin tolerance is induced. The procedures are perfiomed 3-4 times per week. Protective creams from sunlight and antiallergic medications are also prescribed.

Phototoxic dermatitis

What is phototoxic dermatitis?

It is photochemically (by sun rays and chemical substances) evoked inflammatory skin reaction , which occurred in the areas exposed to the sun, without presence of immunological mechanisms. It is commonly appearing photodermatosis. Clinically its features are similar to a sunburn: in the sun exposed areas, after the contact with a chemical substance that causes inflammation, the skin becomes pink, swollen, and blisters and blebs develop.

What causes phototoxic dermatitis?

Usually plants, medications (e.g. antibiotics), either oils cause phototoxic dermatitis.

Photoallergic dermatitis

What is “photoallergic dermatitis”?

The photosensitising substance, which affects the skin locally (or due to its systemic effect), causes delayed allergic reaction. Characteristic skin lesions in the sun exposed skin areas. Usually such reaction is caused by sun protection creams and skin care and treatment measures. Rear type of disease. Diagnosis is approved by photo application test.

If you have any questions, please contact our GK Clinic by phone at (+370) 5 255 33 53 and arrange a private consultation.