Skin, Hair, and Nails

Flashcards covering key vocabulary related to the structure, function, common conditions, and assessment of the skin, hair, and nails.

Skin

The largest organ system, covering 20 square feet of surface area in adults and protecting the body from environmental stresses.

Epidermis

The outer highly differentiated layer of the skin, where the basal cell layer forms new skin cells and the outer horny cell layer consists of dead keratinized cells.

Dermis

The inner supportive layer of the skin, made of connective tissue (collagen) and elastic tissue.

Subcutaneous layer

Beneath the epidermis and dermis, composed of adipose tissue that stores fat for energy, aids in cushioning/protection, and provides increased mobility.

Melanin

A brown pigment that is one of the three main sources determining skin color.

Carotene

A yellow-orange pigment that is one of the three main sources determining skin color.

Hair

Threads of keratin, including the hair shaft and bulb matrix, with types such as vellus and terminal hair.

Vellus hair

Fine, faint hair that covers most of the body.

Terminal hair

Thicker, darker hair found on the scalp, eyebrows, eyelashes, pubic area, and axillae.

Sebaceous glands

Glands that secrete sebum, a lipid substance, through hair follicles to lubricate the skin and form an emulsion.

Eccrine sweat glands

Glands that produce sweat, important for temperature regulation.

Apocrine sweat glands

Glands that produce a milky secretion and open into hair follicles, found in the axillae, anogenital area, nipples, and navel.

Nails

Hard plates of keratin on the dorsal edges of the fingers and toes.

Lanugo

Fine, downy hair covering a newborn infant.

Vernix caseosa

A thick, cheesy substance covering a newborn infant, protecting the skin in utero.

Milia

Small, white papules on the skin of newborns, resulting from sebum holding water in the skin.

Senile purpura

Discoloration of the skin in aging adults due to increasing capillary fragility.

Keloids

Benign excess of scar tissue beyond the original injury, common in certain ethnic groups.

Pallor

A widespread pale color change in the skin, indicating a lack of underlying red tones.

Erythema

A widespread red color change in the skin, often indicating inflammation, fever, or blushing.

Cyanosis

A widespread blue color change in the skin, indicating decreased perfusion and deoxygenated blood.

Jaundice

A widespread yellow color change in the skin, indicating increased bilirubin in the blood.

Diaphoresis

Excessive sweating or moisture on the skin.

Edema

Fluid accumulation in the interstitial space, causing swelling.

Mobility and Turgor

Measures of skin elasticity; mobility refers to the ease of skin rising, turgor refers to its ability to return to place promptly.

Profile sign

Viewing the index finger at its profile to note the angle of the nail base, which should be about 160 degrees.

Capillary refill

A test where depression of the nail edge blanches it, and the return of color indicates the status of peripheral circulation.

ABCDEF Skin Assessment

A rule for detecting suspicious skin lesions: Asymmetry, Border irregularity, Color variations, Diameter greater than 6 mm, Elevation or evolution, Funny looking.

Mongolian spot

A common variant hyperpigmentation in Black, Asian, American Indian, and Hispanic newborns, appearing as a blue-black to purple macular area on the sacrum or buttocks.

Café-au-lait spot

A large round or oval patch of light brown pigmentation, usually present at birth.

Harlequin color change

A benign temporary condition in newborns where one side of the body turns red and the other half remains pale due to immature autonomic nervous system.

Erythema toxicum

A common rash that appears in the first 3 to 4 days of life in newborns, consisting of tiny punctate red macules and papules on the cheeks, trunk, back, and buttocks.

Acrocyanosis

Bluish discoloration around the lips, hands, and fingernails, and feet and toenails of newborns, common in the first few hours after birth.

Cutis marmorata

A transient mottled blue or red pattern over the skin of newborns when exposed to cold.

Physiologic jaundice

Yellowing of the skin, sclera, and mucous membranes in newborns appearing after 24 hours of age and lasting up to a week, due to increased bilirubin levels.

Carotenemia

Yellow-orange color in light-skinned infants, most noticeable on the palms and soles, caused by ingesting large amounts of carotene-rich foods.

Nevus simplex (stork bite)

A common vascular lesion in infants, appearing as a flat, irregularly shaped red or pink patch, usually on the forehead, eyelids, or upper lip and disappears by age 1.

Acne

Skin problems such as pimples and blackheads, common in adolescents due to increased sebaceous gland activity.

Striae

Stretch marks, common in pregnant women due to stretching of the skin.

Linea nigra

A brownish-black line down the midline of the abdomen in pregnant women, due to increased hormone levels.

Chloasma

A discoloration change on the face (mask of pregnancy) in pregnant women, due to increased hormone levels.

Vascular spiders

Tiny red centers with radiating branches occurring on the face, neck, chest, and arms in pregnant women due to increased estrogen.

Solar lentigines (liver spots)

Small, flat, brown macules on elderly adults, primarily in sun-exposed areas.

Keratoses

Raised, thickened areas of pigmentation on aging skin, including seborrheic and actinic types.

Xerosis

Abnormally dry skin, common in aging adults due to decreased sweat and sebaceous gland function.

Skin tags (acrochordons)

Small, fleshy skin growths, commonly found on eyelids, cheeks, neck, axillae, and trunk in aging adults.

Sebaceous hyperplasia

Raised yellow papules with a central depression, common on the forehead, nose, and cheeks of aging adults.

Annular or circular lesion

A lesion that begins in the center and spreads to the periphery.

Confluent lesion

Lesions that run together.

Discrete lesion

Lesions that are distinct and separate.

Grouped lesion

A cluster of lesions.

Gyrate lesion

A lesion that is twisted, coiled, or snakelike.

Target or iris lesion

A lesion that resembles the iris of the eyes, with concentric rings.

Linear lesion

A lesion appearing as a scratch, streak, line, or stripe.

Polycyclic lesion

Annular lesions that grow together.

Zosteriform lesion

A linear arrangement of lesions following a unilateral nerve route.

Macule

A solely color change, flat and circumscribed, less than 1 cm in diameter.

Papule

A lesion felt and caused by superficial thickening of the epidermis, less than 1 cm.

Patch

Macules that are larger than 1 cm.

Plaque

Papules coalescing to form a surface elevation wider than 1 cm.

Nodule

A solid, elevated, hard or soft lesion, greater than 1 cm, that may extend deeper into the dermis than a papule.

Wheal

A superficial, raised, transient and erythematous lesion, irregular in shape due to edema.

Tumor

A lesion larger in diameter, firm or soft, deeper into the dermis, may be benign or malignant.

Urticaria (hives)

Wheals that coalesce to form an extensive pruritic (itchy) reaction.

Vesicle

An elevated cavity containing fluid up to 1 cm (blister).

Cyst

An encapsulated fluid-filled cavity in the dermis or subcutaneous layer.

Bulla

A vesicle larger than 1 cm in diameter, usually single chamber, superficial in the dermis and ruptures easily.

Pustule

A cavity filled with pus that is circumscribed and elevated.

Crust

Thickened, dried-out exudate on the skin surface.

Scale

Compact flakes of desiccated skin from shedding of dead excess keratin cells.

Fissure

A linear crack with abrupt edges extending into the dermis.

Erosion

A scooped-out but shallow depression in the skin, superficial.

Ulcer

A deeper depression extending into the dermis with an irregular shape, may bleed, and leaves a scar.

Excoriation

A self-inflicted abrasion that is superficial.

Scar

Permanent fibrotic change after healing of a skin lesion.

Atrophic scar

A resulting skin level that is depressed with loss of tissue and thinning.

Lichenification

Prolonged intense scratching that leads to thickened skin producing tightly packed sets of papules.

Pressure Injury (Stage I)

Non-blanchable erythema of intact skin.

Pressure Injury (Stage II)

Partial-thickness skin loss involving the epidermis and/or dermis, presenting as a shallow open ulcer.

Pressure Injury (Stage III)

Full-thickness skin loss involving damage to subcutaneous tissue, but not through fascia.

Pressure Injury (Stage IV)

Full-thickness skin/tissue loss with exposed bone, tendon, or muscle.

Port-wine stain (nevus flammeus)

A large, flat, macular patch, ranging from pink to dark purple, present at birth and typically does not fade.

Strawberry mark (infantile hemangioma)

A raised, bright red area with well-defined borders, usually appearing in the first few months of life and resolving by 5-7 years of age.

Spider angioma

A fiery red, star-shaped lesion with a solid circular center, common on the face, neck, and chest.

Venous lake

A blue-purple dilation of venules and capillaries in a star-shaped, linear, or flaring pattern, usually on the legs or face.

Petechiae

Tiny, punctate hemorrhages, 1 to 3 mm, round and discrete, dark red, purple, or brown in color, caused by bleeding from superficial capillaries.

Ecchymosis

A purplish patch resulting from extravasation of blood into the skin, greater than 3 mm in diameter (a bruise).

Purpura

Confluent and extensive patch of petechiae and ecchymosis, greater than 3 mm, flat, red to purple, macular hemorrhage.

Contusion (bruise)

A mechanical injury caused by direct trauma to the skin and underlying tissues, resulting in hemorrhage and skin discoloration.

Diaper dermatitis

Red, moist, maculopapular rash with poorly defined borders, found in the diaper area of children.

Candidiasis

A fungal infection presenting as a scalded appearance of the skin, with bright red patches, loose scales, and pustules.

Impetigo

A common bacterial skin infection in children, characterized by thin-walled vesicles with a honey-colored crust.

Atopic dermatitis (eczema)

A chronic inflammatory skin condition characterized by pruritus, erythema, excoriation, and lichenification, often in children.

Measles (rubeola)

A viral infection characterized by a red-purple maculopapular rash that starts behind the ears and spreads over the body, along with Koplik spots in the mouth.

German measles (rubella)

A milder viral illness characterized by a pink, papular rash similar to measles but with a shorter duration.

Chickenpox (varicella)

A highly contagious viral infection with small, tight, shiny vesicles on an erythematous base, progressing to pustules and then crusts.

Primary contact dermatitis

An inflammatory skin reaction caused by direct contact with an irritant or allergen, characterized by erythema, swelling, vesicles, and pruritus.

Tinea corporis (ringworm of the body)

A fungal infection of the body, presenting as a circular lesion with clear center and raised borders.

Tinea pedis (athlete's foot)

A fungal infection of the foot, often between the toes, characterized by scaling, maceration, and fissures.

Labial herpes simplex (cold sores)

Clusters of small vesicles on an erythematous base, usually on the lips or mouth, caused by the herpes simplex virus.