What is contact dermatitis?
Contact Dermatitis is an acute or chronic dermatitis that results from direct skin contact with chemicals or allergens.
These agents could be Chemicals, Animal or plant products, Physical agents like heat, cold, ultraviolet rays or ionizing radiation.
Classification of Contact dermatitis
Contact dermatitis is classified as:
- Irritant dermatitis
- Acute irritant dermatitis,
- Cumulative insult dermatitis
- Allergic contact dermatitis
- Phototoxic dermatitis
- Photo-allergic dermatitis
Symptoms and clinical features of contact dermatitis
1. Acute phase
- Tiny vesicles, weepy and crusted lesions
2. Resolving or chronic contact dermatitis
- Scaling, erythema, and possibly thickened (lichenified) skin
- Itching, burning, and stinging may be severe
Contact dermatitis is recognized by the
distribution and configuration of the lesion which usually corresponds to the contactant e.g.
- Face: cosmetics
- Photodermatitis: airborne allergens e.g. dust, fumes, sprays
- Neck: nickel necklace, perfume, and collars of garments
- Hands: various chemicals handled at home, at work and at leisure hours
- Feet: shoes, socks, remedies for athletes’ foot, etc
Differential diagnoses
- Atopic dermatitis
- Seborrhoeic dermatitis.
- Psoriasis
- Dermatophyte infection
- Lichen planus
- Face: lupus erythematosus, pellagra, rosacea
Complications of contact dermatitis
- Impetiginization
- Secondary dissemination
Investigations
- Patch test
- Occupational site assessment
Treatment for contact dermatitis
Treatment objectives
- Cure the dermatitis.
- Identify cause(s) and avoid further contact
Drug treatment
As for atopic dermatitis
Supportive measures
- Counselling (after identifying the cause)
- Allergen replacement