William Pinette30 July, 2010

Toxicodendron diversilobum, Poison-oak

Contact Dermatitis: “Contact dermatitis is an eczematous skin reaction caused by direct and usually repeated exposure to harmful objects or chemicals … It is typically characterized by itching papules ... but may vary from slight hyperkeratosis ... and small fissures to extensive redness, swelling and oozing. A histopathological examination of a biopsy shows an acute inflammation in the epidermis.”

– European Society for Contact Dermatitis

Allergic Contact Dermatitis

Irritant Contact Dermatitis

Immune response Delayed Type Hypersensitivity T lymphocytes

Allergens Toxicodendron

Urushiol Nickel and other metals Latex Chemicals

Formaldehyde Perfume

No direct immune response Exposure to irritants that

compromise the epithelium in various ways Industrial Solvents Oil products Hair products Dimethyl Fumarate

(DMF)

ACD Cannot “cure” the immune system. Avoid exposure to allergen Wash affected area with soap and cool water Corticosteroids and antihistamine for more

severe cases ICD

Avoid prolonged exposure to irritants Personal protective equipment Barrier creams

What is contact dermatitis? European Society of Contact Dermatitis. http://www.escd.org/aims/contact_dermatitis

Kalish RS, Johnson KL. Enrichment and function of urushiol (poison-ivy)-specific T Lymphocytes in lesions of allergic contact dermatitis to urushiol. J Immunol.(1990) 145: 3706-3713

Niyama et. al. Th2 Immune Response Plays a Critical Role in the Development of Nickel-Induced Allergic Contact Dermatitis. Int Arch Allergy Immunol (2010). 153: 303–314

Gimenez-Arnaui et al. Shoe contact dermatitis from dimethyl fumarate: clinical manifestations, patch test results, chemical analysis, and source of exposure. Contact Dermatitis (2009) 61: 249–260

Chew IL, Maibach HI. Occupational issues of irritant contact dermatitis. Int Arch Occup Environ Health (2003) 76: 339–346