Photoallergic dermatitis L56.1

Author: Prof. Dr. med. Peter Altmeyer

All authors of this article

Last updated on: 29.10.2020

Dieser Artikel auf Deutsch

Synonym(s)

Dermatitis photoallergic; Photoallergen; Photoallergic contact eczema; photoallergic dermatitis; Photoallergic dermatitis; Photoallergic eczema; Photoallergic reaction; Photoallergy; Photo contact allergy; Photocontact allergy

Definition
This section has been translated automatically.

Photoallergically triggered dermatitis after previous specific sensitization, caused by systemically or externally applied substances that are not necessarily phototoxic.

Photoallergic dermatitis occurs mainly in exposed areas (see also photoallergy and photoallergen) but, in contrast to photoxic dermatitis, is not sharply limited to the contact area.

Occurrence/Epidemiology
This section has been translated automatically.

In middle-aged or elderly patients who are taking photoallergically effective medication (see below drug reaction, undesirable).

Etiopathogenesis
This section has been translated automatically.

Triggered by photoallergenic(see below photoallergenic) substances (also drugs) which enter the skin through local application or systemically and are photochemically stimulated there by UV rays of different wavelengths (mostly UVA rays) (UVB is only triggered in a few cases - e.g. chlorpromazine).

The full antigen, which is produced by different processes, leads to a sensitization and in case of re-exposure to a T-cell-mediated type IV reaction (see below allergy).

Some systemically applied "photoallergens" are also effective as contact allergens, so that the tests are complicated and their significance is only meaningful if the patient's medical history and clinic are taken into account.

Localization
This section has been translated automatically.

Exclusively in light-exposed areas. Face with recess of the shaded skin regions (chin shadow, retroauricular, axillary), neck, nape of neck, chest region (décolleté); back (clothing cut-outs), forearms and upper arms (accentuated on the straight side); back of hands;

Clinical features
This section has been translated automatically.

The heliotropic macro-pattern is characteristic and thus diagnostically groundbreaking, whereby the micro-pattern shows the picture of chronic polymorphic dermatitis (so-called eczema reaction) of varying acuteity and severity (erythema, papules, papulo-vesicles, extensive scaling and itching).

In contrast to phototoxic dermatitis, the"contact pattern" is not sharply focused on the contact areas but, as in contact allergic eczema, is blurred with "dermatitic scattering foci" beyond the UV exposure site.

Histology
This section has been translated automatically.

Image of spongiotic dermatitis (see eczema below).

Diagnosis
This section has been translated automatically.

Depending on the suspected photoallergen (photocotactic allergen or systemically applied substance) a photopatch test or systemic photoprovocation must be carried out.

Complication(s)
This section has been translated automatically.

With continued exposure to allergens, the clinical picture can change into a chronic, self-releasing form (chronic photoallergic contact eczema).

Therapy
This section has been translated automatically.

Allergen avoidance, avoidance of direct sunlight, sun protection, external glucocorticoids such as 0.1% hydrocortisone butyrate (Laticort cream) or 0.1% triamcinolone cream (Triamgalen, R259 ), 0.05% betamethasone V lotio (Betagalen, R030 ) or 0.1% mometasone (e.g. Ecural ointment). If necessary, antihistamines such as desloratadine (e.g. Aerius) 1-2 tbl/day.

Note(s)
This section has been translated automatically.

The most frequent triggers of photoallergic contact eczema in Europe are currently topical NSAIDs (e.g. ketoprofen, etofenamate) as well as organic light protection filters (e.g. octocrylene, benzophenone-4 as well as butyl-methoxydibenzoylmethane, which is widely used in cosmetic creams with "light protection".

Literature
This section has been translated automatically.

  1. Altmeyer P et al (2007) Dermatological differential diagnosis. Springer Medicine Publishing House
  2. Giudici PA et al (1985) Experimental photoallergy to systemic drugs. J Invest Dermatol 85: 207-211
  3. Lehmann P et al (2011) Light dermatoses: Diagnostics and therapy. Dtsch Ärztebl 108: 135-14
  4. Mahler V (2015) Contact eczema. Act Dermatol 40: 95-107

Disclaimer

Please ask your physician for a reliable diagnosis. This website is only meant as a reference.

Authors

Last updated on: 29.10.2020