skin lesions and pressure injuries

Macule

Primary lesion

flat and circumscribed

less than 1 cm

Ex.

freckles, flat nevi, hypopigmentation, petechiae, measles, scarlet fever.

Patch

Primary skin lesion

Macule that are larger than 1 cm

mongolian spot, vitiligo, café au lait spot, chloasma, measles rash

Papule

Primary lesion

Something you can feel

solid, elevated, circumscribed

less than 1 cm

caused by superficial thickening in epidermis.

elevated nevus (mole), lichen planus, molluscum, wart (verruca).

Plaque

Primary lesion

Papules coalesce to form surface elevation wider than 1 cm

psoriasis, lichen planus.

Nodule

Primary lesion

Solid, elevated, hard or soft, larger than 1 cm

May extend deeper into dermis than papule

xanthoma,fibroma, intradermal nevi.

Tumor

Primary lesion

Larger than a few centimeters in diameter

firm or soft ,deeper into dermis

may be benign or malignant

lipoma, hemangioma.

Wheal

Primary lesion

Superficial, raised, transient, and erythematous

slightly irregular shape from edema

mosquito bite, allergic reaction, dermographism.

Urticaria ()

Primary lesion

Hives

Wheals coalesce to form extensive reaction, intensely

pruritic.

Vesicle

Primary lesion

Elevated cavity containing free fluid

up to 1 cm

Clear serum flows if wall is ruptured.

Blisters, herpes simplex, early varicella (chickenpox), herpes zoster

(shingles), contact dermatitis

Bulla

Primary lesion

Larger than 1 cm diameter

usually single chambered

superficial in epidermis

thin-walled and ruptures easily

friction blister, pemphigus, burns, contact dermatitis

Cyst

Primary lesion

Encapsulated fluid-filled cavity in dermis or subcutaneous layer

elevating skin

sebaceous cyst, wen

Pustule

Turbid fluid (pus) in the cavity

Circumscribed and elevated.

impetigo, acne.

Crust

Secondary lesion

thickened, dried-out exudate left when vesicles/ pustules burst or dry up.

red-brown, honey, or yellow,

impetigo (dry, honey-colored), weeping eczematous dermatitis, scab after abrasion.

Scale

Secondary lesion

Compact,

desiccated flakes of skin, dry or greasy, silvery or white,

from shedding of dead excess keratin cells.

after scarlet fever or drug reaction (laminated sheets), psoriasis (silver, micalike), seborrheic dermatitis (yellow, greasy), eczema, ichthyosis (large, adherent, laminated), dry skin.

Fissure

Secondary lesion

Linear crack with abrupt edges;

extends into dermis;

dry or moist.

cheilosis—at corners of mouth caused by excess moisture; athlete’s foot.

Erosion

Secondary lesion

Scooped-out but shallow depression.

Superficial; epidermis lost;

moist but no bleeding;

heals without scar

erosion does not extend into dermis.

Ulcer

Secondary lesion

Deeper depression extending into dermis,

irregular shape;

may bleed; leaves scar when heals.

stasis ulcer, pressure injury, chancre.

Excoriation

Secondary lesion

Self-inflicted abrasion;

superficial;

sometimes crusted; scratches from intense itching.

insect bites, scabies, dermatitis, varicella.

Lichenification

Secondary lesion

Prolonged, intense scratching eventually thickens skin and

produces tightly packed sets of papules; looks like surface of

moss (or lichen).

Keloid

Secondary lesion

A benign excess of scar tissue beyond sites of original

injury: surgery, acne, ear piercing, tattoos, infections,

burns.16 Looks smooth, rubbery, shiny, and “clawlike”;

feels smooth and firm.

Stage 1—Non-Blanchable Erythema

Intact skin is red but unbroken. Localized redness in lightly

pigmented skin does not blanch

Dark skin appears darker but does not blanch.

May have changes in sensation, temperature, or firmness.

Stage 2—Partial-Thickness Skin Loss

Loss of epidermis and exposed dermis. Superficial ulcer looks shallow like an abrasion or open blister with a red- pink wound bed. No visible fat or deeper tissue.

Stage 3—Full-Thickness Skin Loss

extends into subcutaneous tissue and resembles a crater. See subcutaneous fat, granulation tissue, and rolled edges, but not muscle, bone, or tendon.

Stage 4—Full-Thickness Skin/Tissue Loss

all skin layers and extends into supporting tissue.

Exposes muscle, tendon, or bone, and may show slough

(stringy matter attached to wound bed) or eschar (black or

brown necrotic tissue), rolled edges, and tunneling.