Atopic Triad

Fillagrin gene

Infancy

Red vessicles or plaques with scaling, oozing, crusting

Childhood - papular, lichenified plaques, excoriations

Cheekx

Dennie-Morgan fold

24-48 hrs after exposure

Allergic or Irritant

Neosporin, sunburn products

Erythema and Greasy Scale

Scalp, Malar Region

Chronic relapsing

Parkinson's, HIV

Lower Legs

Erythematous patches and plaques

Venous insufficiency

Pruritic, bilateral (whereas celulitis is usually unilateral and often painful)

Older people, hypothyroidism

Leukemia/Lymphoma

Coin

Chronic, pruritic

Winter

Papules/Plaques covered with scale, thicker, more elevated, and sharply demarcated (all in contrast to dermatitis)

Psoriasis, Lichen Planus, Pityriasis Rosea, Tinia (Pityriasis) Versicolor

Ham red plaques, silvery scale

Elbows, knees, psoriatic nails

Hyperproliferation

Psoriatic arthritis 

Violet, flat-topped

Intensely pruritic

Flexor wrists

Hep C

Possible Squamous Cell precursor

DK

Mild pruritis

Harold Patch

Fungal 

Hyperpigmented - winter

Hypopigmented - summer