Contact dermatitis
Background
- Type IV hypersensitivity reaction
- Three Types
- Allergic contact dermatitis: nickel, gold, chromium, poison ivy, poison oak, and poison sumac
- Irritant contact dermatitis: solvents, neat oils, kerosene, surfactants in cosmetics, latex, drain cleaners
- Photocontact dermatitis: interaction with UV light (lime juice and sunlight)
Clinical Features
- Inflammation of the epidermis and dermis
- Erythema may take 1-3 days to show up
- May also have blisters and wheels
- Form in linear or shaped-pattern depending on exposure
- Itchy, burning, and sometimes painful
- Can take weeks to heal
Differential Diagnosis
Generalized Rash
- Allergic reaction
- Aphthous stomatitis
- Atopic dermatitits
- Cellulitis
- Chickenpox
- Chikungunya
- Coxsackie
- Dermatitis herpetiformis
- Erysipelas
- Erythema multiforme
- Henoch-schonlein purpura
- Hives
- Impetigo
- Measles
- Miliaria (Heat Rash)
- Necrotizing fasciitis
- Poison Oak, Ivy, Sumac
- Psoriasis
- Pityriasis rosea
- Scabies
- Seborrheic dermatitis
- Serum Sickness
- Smallpox
- Shingles
- Stevens-Johnson syndrome and toxic epidermal necrolysis
- Tinea capitus
- Tinea corporis
- Vitiligo