Ch. 41 Skin Disorders

Albinism

genetic disorder that strips skin, hair, nails of melanin

Vitiligo

acquired skin condition caused by abnormalities in melanin production

Melasma

dark macules on face (freckles)

Lentigos

larger, dark pigmented spots on face

Acanthosis nigricans

dark/brownish-black, velvety thickening of skin (associated with diabetes)

Xerosis

dry, scaly, rough, wrinkled skin that is more easily bruised/irritated

Pruritis

localized or systemic itching

Telogen effluvium

number of resting hair follicles increase and number of growing hair follicles decrease (hair thins)

Alopecia areata

sudden loss of hair in 1 area of scalp

Clubbed fingernails

exhibit Schamroth sign: obliteration of diamond-shaped space at proximal end of nail when distal phalangeal bones are opposed

Beau's lines

transverse, linear depressions across nail caused by trauma or Raynaud's syndrome

Koilonychia

spooning of nails

Yellow nail syndrome

nails thicken and discolor (occur in rheumatoid arthritis, immunodeficiency, malignancies, pulmonary problems)

Splinter hemorrhages

occur in endocarditis

Onycholysis

nails separate from nail beds (occur in thyroid or autoimmune disease)

Subungual hemorrhage

black region beneath nail due to trauma

Leukonychia

short white lines in nail due to trauma

Muehrke's lines

transverse white lines that indicate hypoalbuminemia

Paronychia

nail disease caused by bacterial or fungal infection producing pain, redness, and swelling

Onychomycosis

fungal or yeast infection in proximal and lateral nail folds

Acne vulgaris

inflammatory disorder of sebaceous gland with comedone (prototypical lesion in acne)

Acne rosacea

inflammatory disorder of sebaceous gland with irreversible swelling and inflammation of nose (rhinophyma)

Hemangioma

benign tumors of blood vessels

Strawberry hemangioma

enlarged blood vessels that grow rapidly after birth

Spider vein

enlarged blood vessels that grow with age

Mongolian spot

benign, darkened area of skin (commonly on back)

Portwine strains

permanent blood vessel abnormalities that darken and enlarge with age

Nevi

moles (most common benign skin tumor)

Actinic keratosis

premalignant lesion

Lentigos

premalignant lesion

Dysplastic Nevus

premalignant stage of melanoma

Verrucae

warts

Tinae

ringworm

Scabies

mite bites

Lyme disease

tick bites cause Borrelia infection

Cimex Lectularius

bed bugs

Pediculosis

lice

West Nile viral infections

mosquito bites

Hymenopteria

bites and stings that cause anaphylactic reaction

Pulicosis

flea bites

Stasis ulcers

decreased leg circulation and valves in legs become obstructed resulting in pooling of venous blood in legs

Contact Dermatitis

delayed hypersensitivity to metals, chemicals, drugs, poison ivy resulting in allergic skin reaction

Seborrheic Dermatitis

inflammation of skin caused by excessive secretions of sebaceous glands

Psoriasis

genetic, chronic thickening of epidermis that presents as overlying silver-white scales covering red, circumscribed, thickened plaques (Auspitz sign)

Acute Urticaria

Hives

Chronic Urticaria

autoimmune disorder (hives)

Scleroderma

autoimmune disorder that affects skin's CT and blood vessels altering skin appearance/flexibility/restricting movement

Lupus Erythematosus

inflammatory autoimmune disease limited to skin or a diffuse multiple system problem

Erythema Multiforme

autoimmune disease with recurring inflammation of skin and mucous membranes associated with allergic or toxic reactions to drugs or microorganisms

Toxic Epidermal Necrolysis

Vesiculobullous form of erythema multiforme with bullae appearing on mucous membranes and plaques on extensor surfaces of extremities