6 terms


Atopic dermatitis (AD) = Eczema
-Immune-mediated skin inflammation, with typically a genetic component.
•Causes: genetic component, food and environmental allergies; Aggravated by dry skin, wool, sweating, allergens, emotional stress.
•S/Sxs: Usually appears in infancy as red, weeping, crusted lesions on face, which spreads to neck, extremities, & abdomen. As condition becomes chronic > lichenification of macules/papules. In adults, presents on flexor surfaces of elbow and knee, buttocks, neck, hands. Very Itchy!!
•Diagnosis: H & P
•DDX: seborrheic derm, contact derm, nummular derm, Candida
Contact dermatitis
-Acute inflammation of skin caused by irritants or allergens

•Irritant contact derm: 80% of cases. Chemicals, soap, plants, or body fluids. Non-specific inflammation rxn. MORE PAINFUL

•Allergic contact derm: Hypersensitivity Type IV reaction with an initial sensitization, then rxn on re-exposure. Drugs, latex, metals, cosmetics, or fragrances. INTENSELY ITCHY

•S/Sxs: ICD is more painful, ACD is intensely pruritic. Mild erythema to hemorrhage, vesiculization and ulceration.

•Dx: H & P (including occupation, hobbies, household duties, travel, topical exposures). Patch testing when ACD doesn't respond to treatment

•DDX: seborrheic derm, atopic derm, nummular derm
Lichen simplex chronicus (neurodermatitis)
-dry, scaling, itchy skin created by repeated scratching which causes further itching and scratching.
-often occurs in ppl w/ anxiety disorders and non-specific emotional stress. Scratching is self-soothing mechanism.

•S/Sxs: pruritic, dry, scaling, hyperpigmented lichenified plaques in irregular, oval, or angular shapes. Often on ankles from rubbing in bed.
•Diagnosis: H & P, KOH wet mount (to differentiate from tinea), biopsy
•DDX: tinea, lichen planus, psoriasis
Nummular Dermatitis
-Inflammation of the skin in a coin-shaped pattern.
-Idiopathic. Mostly middle-aged pts. w/ dry skin
•Mostly mid-aged pts with dry skin. Idiopathic.
•S/Sxs: inflamed, coin-shaped lesions, vesicular, crusting, and scaling, as well as pruritic. Extensor surfaces of extremities, buttocks, and trunk.
•Diagnosis: H & P, biopsy, KOH wet mount (to rule out fungus)
•DDX: Tinea corporis, scabies, seborrheic dermatitis, fungus, Paget's disease when on the breast.
Seborrheic dermatitis
-Inflammation of skin in areas of skin w/ high density of sebaceous glands (scalp, eyebrows, eyelids, face)

•S/Sxs: gradual onset, dry or greasy scaling of scalp (dandruff), hairline, posterior ears, external auditory canals, eyebrows, axillae, bridge of the nose, nasolabial folds, over the sternum. May see papules. NO HAIR LOSS. CRADLE CRAP in newborns.

•Diagnosis: H & P

•DDX: atopic dermatitis, contact dermatitis, psoriasis, tinea
Stasis dermatitis
-Persistent dermatitis of the lower legs, especially the ankle, secondary to chronic venous insufficiency

•S/Sxs: Hyperpigmentation (red-brown) develops over time. Often edema and petechiae. Later erythema, weeping, crusting. May see varicosities, and cellulitis. Often develop stasis ulcers that do not heal, and may penetrate to the bone.

•Diagnosis: H & P

•DDX: cellulitis, contact dermatitis