Types of patterns:
(1) based on size and shape
(2) based on location
(3) uncommon with special features
Types based on the size and shape of skin lesions:
(1) guttate (small and "drop-like")
(2) discoid or plaque (psoriasis vulgaris): lesions may be small or large
(3) pustular: may be local or generalized, may form along the rim of plaques
Types based on location:
(1) scalp
(2) flexural (inverse): occur in axilla, genital folds, neck or other intertriginous areas (skin creases)
(3) palmar-plantar: may be hyperkeratotic or pustular
(4) photosensitive: involvement worse on sun-exposed surfaces
Uncommon types with special features:
(1) erythrodermic: diffuse erythema
(2) elephantine: large plaques with leathery texture resembling elephant hide
(3) geographic: fused plaques covering a large area of skin
(4) ostraceous: very thick and scaly, resembling an oyster shell
(5) lichenified: thickened and eczematoid
(6) rupioid: cone-shaped or limpet-like plaques
(7) annular: ring-shaped with central clearing
(8) linear: arranged in lines
Patterns associated with more serious disease:
(1) extensive plaque psoriasis (includes geographic)
(2) generalized pustular
(3) erythrodermic
