Photodermatitis

Photodermatitis

Photodermatitis is polyetiological dermatoses induced by solar radiation.

Classification and etiology

• • Phototoxic dermatitis occurs under the influence of the ultraviolet part of solar radiation.

effects on the skin, more often as a result of exposure directly to it of certain substances (the juice of certain plants [hogweed, dill, parsley], drugs [tar and its derivatives, sulfonamides], household chemicals [photoactive dyes – eosin, acridine orange, bergamot oil] )

• • Photoallergic dermatitis develops as a result of the combined action of an allergic and / or toxic photosensitizing substance (phenothiazine derivatives, tetracyclines, sulfanilamide products, oral contraceptives) and solar radiation
  • Polymorphic photodermatitis (polymorphic light-dependent rash) is a chronic recurrent hereditary photodermatitis.

Clinical picture

• • Phototoxic dermatitis traditionally develops soon after sun exposure. Skin hyperpigmentation traditionally occurs after resolution of acute symptoms.
  • Erythema, in severe cases – blisters, blisters
  • Pain
  • Clear boundary between affected and unaffected skin
  • In chronic phototoxic dermatitis – thickening of the epidermis, elastosis, telangiectasia and hyperpigmentation.
  • Photoallergic dermatitis usually develops a day later or later as a result of sun exposure –
  • Erythema, papules, sometimes blisters
  • Itching
  • Areas of affected skin have less clear boundaries, and non-irradiated areas may also be involved in the process.
  • Polymorphic photodermatitis traditionally develops a few hours later as a result of sun exposure and only in the spring-summer period.
  • Burning or itching traditionally precedes skin manifestations
  • Erythematous, urticarial (urticaria), papular, bullous rashes; sometimes the rash resembles erythema multiforme exudative
  • The first rashes are traditionally found on the skin of the forehead, chin, auricles, the rash can spread to non-irradiated areas.
  • Often observed conjunctivitis, cheilitis, worsening of the general condition
  • The rash usually resolves in 2-3 weeks, but recurs after another sun exposure.

Drug therapy

• • Glucocorticoid ointments: beta-methasone, fluorocort, etc.
  • NSAIDs: indomethacin 25 mg 3 times a day, acetylsalicylic acid, etc.
  • Antihistamines for itching
  • Chloroquine 0.2-0.25 g 2 r / day in cycles of 5 days
  • Glucocorticoids by mouth or parenterally in severe cases: for example, prednisolone 0.5–1 mg/kg/day for 3–10 days
  • Nicotinic acid or xanthinol nicotinate, B vitamins.

The prognosis is favorable.

Prevention

• • Sun exposure must be avoided
  • Sun protection clothing, sunscreen
  • Do not take photosensitizing drugs. ICD. L56 Other acute skin changes caused by ultraviolet radiation