Allergic, Hypersensitivity, and Inflammatory Skin Disorders

what is allergic contact dermatitis?

Inflammatory response due to sensitization to an allergen (such as poison ivy)

what are causative agents of allergic contact dermatitis?

Dyes and perfumes, topical antimicrobial agents, local anesthetics, preservatives, adhesive tape, poison oak and ivy, metals, latex

what are clinical manifestations of allergic contact dermatitis?

Erythema with edema to large vesicles, location based on where the exposure occurred on the skin

what is atopic dermatitis (atopic eczema)

Chronic, relapsing skin inflammation with pruritus

what are clinical manifestations of atopic eczema?

• Dry red patches of the face, neck, and upper trunk in adults and adolescents; often in the bends of the elbows and knees

• Itching may produce a secondary infection

• Acute flare-ups—Red patches that are weepy, shiny, or thickened

what is atopic dermatitis (drug-induced skin eruptions)?

topical drugs produce local rashes and systemic drugs produce generalized skin lesions

what is erythema multiforme minor?

Small amount of skin detachment at the lesion site; self-limiting

what is stevens-johnson syndrome?

• Hypersensitivity reaction to drugs (sulfonamides, anticonvulsants, NSAIDs) or virus

• Skin detaches from the body surface

what are clinical manifestations of drug-induced skin eruptions?

• Round papule (raised, reddened area) that may enlarge or coalesce

• Blisters form in the center on dusky macules (flat area)

  • Gives a “target” appearance

what is toxic epidermal necrolysis (TEN)?

Greater than 30% of epidermis detaches, may affect the mouth and eyes and can lead to blindness

what is an example of papulosquamous dermatoses?

psoriasis

what is psoriasis?

chronic inflammatory disorder characterized by scaling papules and plaques starting in the 30s and increasing with age

what are risk factors of psoriasis?

• Family history for children with psoriasis

• Some association with arthritis

• Exacerbations with stress, infection, trauma, medications

what are the several types of psoriasis?

• Thick red plaques with silvery scales

• Teardrop shaped pink scaly lesions of trunk and extremities

• Plaque—Most common; affects elbows, knees, scalp

• Guttate—Children and young adults