Skin Flashcards
Skin Function
- Keep body in homeostasis from environment.
- Boundary for body fluids.
- Maintain body temperature, make vitamin D.
- Protect underlying tissues from microorganisms, harmful substances, and radiation.
Epidermis
Most superficial, thin, devoid of blood vessels
2 layers
- outer horny layer of dead keratinized cells
- inner cellular layer where both melanin and keratin are formed
Depends on dermis for nutrition
Serves as barrier to prevent fluid loss and infection. Contains specialized organ cells. Keratinocytes, melanocytes, Langerhans cells
Dermis
Two layers of varying thickness. Provide circulation, nutrition, and support. Contains sebaceous and sweat glands, hair follicles. It merges with subq layer.
Contains specialized organs - vascular structures, nerves, mast cells, fibroblasts, macrophages, dendritic cells
Subcutaneous tissue
Layer of loose CT beneath dermis.
Contains adipose cells, fibroblasts, hair follicle roots, blood vessels, Lymphatic vessels, nerve free endings
Hair
Terminal, Vellus
Nails
Plate, Bed, Lunule, eponychium, hyponchium, proximal, and lateral nail folds
Primary lesions
Macula, patch, papule, plaque, nodule, vesicle, bulla, pustule, tumor, wheal
Secondary lesions
May have evolved from primary lesions. Or caused by external forces or over treatment
Scale, excoriation, fissure, crust, erosion, ulcer, cicatrix, atrophy
Special skin lesion
Comedone, milia, cyst, burrow, lichenification, telangiectasia, petechiae, purpura
Primary
Physical changes caused by disease process. Initial presentation. Not specific to a single disease
Macule ** TQ
Small, flat, non-palpable lesion. Less than 1 cm diameter
Ex. Junctional nevus (birthmark), ephelides (freckles), solar lentigo (sunspots)
Patch
Flat, non-palpable lesion
1 cm or larger in diameter (huge macula)
Papule
Raised, solid lesion, small superficial, elevated above skin surface. Less than 1 cm ex pimple
Plaque
Palpable lesion elevated above skin surface. 1 cm or larger in diameter ex. Psoriasis
Nodule
Firm lesion thicker and deeper than plaque. Huge plaque greater 0.5 cm elevation.
Ex. Huge boil
Vesicle
Elevated lesion with clear fluid. Less than 1 cm in diameter ex. Blister
Bulla
Elevated lesion with clear fluid. Greater than 1 cm diameter (huge vesicle)
Pustule
Elevated lesion with pus within or beneath epidermis. Pimple with pus
Wheal/Hives
Slightly reddened, changing in size/shape
Excoriation **TQ
Linear breaks in skin surface. Covered with blood/crusts ex. Scratch mark
Cicatrix (scar) ***TQ
Hypertrophic keloid
Ulcer
Lesion on surface/mucosal surface. Caused by loss of tissue with inflammation
Erosion
Wearing away or state worn away. Shallow ulcer
Crust
Hard outer layer or covering. Dried serum or pus on surface
Atrophy
Wasting of tissue from death/reabsorption of cells, ischemia, malnutrition, etc
Sclerose
To harden, undergo sclerosis (hardening)
Necrosis
Pathologic death from irreversible damage
Lichenification ** TQ!
Leathery induration and thickening of the skin
ABCDE’s of Melanoma ***** TQ!!
A - asymmetry B- border irregularity C- color D- diameter more than 6 mm E- evolution/elevation F- funny looking
Melanoma risk factors
HARMM History of previous melanoma Age over 50 Regular dermatology absent Mole changing Male Gender Others- freckles, light eye or skin color, red or light hair, UV radiation from heavy skin exposure sunlamps or tanning booths, 50+ common moles, family history of melanoma, and Nevis that are changing or atypical, especially if > 50 y/o
Skin color depends on
4 pigments
Melanin: brownish pigment, increased with exposure to sunlight, genetically predetermined
Carotene: golden yellow in subcutaneous fat and heavily keratinized areas (palms & soles)
Oxyhemoglobin: bright red, predominates in arteries and capillaries
Deoxyhemoglobin: darker bluer, predominates in capillaries and veins
Appendages of skin
Hair: vellus (short, fine, nonpigmented) or terminal (courser, thicker, conspicuous, usually pigmented)
Nails: lanula (white free edge of nail plate), cuticle (seal between proximal nail fold and nail plate)
Sweat glands: eccrine= everywhere (reg body temperature); apocrine = axillary and genitals (stress, stench comes from bacterial decomposition)
Sebaceous glands: fatty substance produced through hair follicle = everywhere but palms and soles
changes in skin which represent disease - color, moisture, temperature, texture, mobility, turgor, lesions
Color: increased pigment, pigment loss, redness, pallor, cyanosis, yellowing (carotenoma), cafe-au-lait spot (macule or patch of pigmentation), tinea versicolor (infection, hypopigmented, slightly scaly macule), vitiligo (loss of pigment completely), erythema (red hue), heliotrope (purple eyelids)
Moisture: dry, sweating, oiliness
Temperature: general or localized warm or cool
Mobility and turgor: decreased mobility, decreased turgor
Lesions: acne (face, upper chest, back), psoriasis (knees, elbows), Candida Infections (genitals), vesicles in unilateral dermatomal pattern (herpes zoster), local redness (impending necrosis )
Changes in hair which represent symptoms of disease
Alopecia (hair loss), sparse hair, fine and silky hair
Changes in nails which may represent symptoms of disease
Paronchia (red, swollen, and tender nail folds), clubbing, oncholysis (enlarged nail free edge), Terry’s nails (ground glass appearance, distal band of reddish brown, obliteration of lunula), white spots (leukoychia), traverse white bands (Mees’ lines), transverse linear depressions (Beau’s lines), pitting (punctuate nail plate depressions)
Nail clubbing
A bulbous swelling of the soft tissue at the nail base with loss of the normal angle between the nail and the proximal nail fold (increased to 180 degrees or more), nail bed feels spongy or floating
The mechanism is unknown but involves vasodilation with increased blood flow to the distal portion of the fingers and changes in CT (possibly from hypoxia). It also involves changes in innervation, genetics, or a platelet derived GF from fragments of platelet clumps
Seen in congenital heart disease, interstitial lung disease, lung cancer, inflammatory bowel disease and malignancies
Urticaria
Aka hives, a raised, itchy wheal that is usually a sign of an allergic reaction
Pruritus
Clinical term for itch
Erythema
Red hue due to increased blood flow (ie slapped cheeks seen in 5th disease)
Petechiae
Small (1-3 mm) red or purple spot on the body, caused by a minor hemorrhage (broken capillary blood vessels)
Purpura
Red or purple discoloration on the skin that do not blanch on applying pressure. Caused by bleeding underneath the skin. Purpura measure 0.3 (3 mm) - 1 cm, whereas petechiae measure less than 3 mm
Ecchymosis
Bruise greater than 3 mm, purple, blood outside cells
Scar
Connective tissue that arises from injury or disease
Alopecia
Round or oval patches of hair loss, usually affecting young adults and children. No visible scaling or inflammation
Keloid
Hypertrophic scarring extending beyond the borders of the initial injury
Lichenification
Visible and palpable leathery induration and thickening of the epidermis, often from chronic rubbing
Blanchable
When pressure applied to an area causes the area to become “white” as blood is pushed out of the blood vessel. Upon release, the blood returns to the area and the skin or nail turns pink.
Blanchable lesions:
- erythema
- spider angioma (liver disease)
- spider vein (varicosities)
- cherry Angioma (benign)
Cyst
Nodule filled with liquid or semisolid material
Burrow
(Scabies) slightly raised tunnel in epidermis, short gray line
Fissure
A linear crack in the skin (ex athletes foot)
Scale
Thin flake of exfoliated epidermis
Burrow of scabies
A person with scabies has intense itching. Skin lesions include small papules, pustules, lichenified areas, and excoriations
Comedo
The common blackhead
Nevus
The common mole
Telangiectasias
Dilated small vessels (can be venues, arterioles, including spider angioma or capillaries) that look either red or bluish (ex spider angioma, spider vein)
Spider angioma- color, size, shape pulsatility, effect of pressure, distribution, significance
Color: Fiery red
Size: From very small to 2 cm
Shape: Central body, sometimes raised, surrounded by erythema and radiating legs
Pulsatility: Often demonstrable in the body of the spider, when pressure with a glass slide is applied
Effect of pressure: Pressure not he body causes blanching of the spider
Distribution: Face, neck, arms, upper trunk; almost never below the waist
Significance: liver disease, pregnancy, vitamin B deficiency, also occurs normally in some people
Spider vein- color, size, shape pulsatility, effect of pressure, distribution, significance
Color: bluish
Size: variable, from very small to several inches
Shape: variable. May resemble a spider or be linear, irregular, cascading
Pulsatility: absent
Effect of pressure: pressure over the center does not cause blanching, but diffuse pressure blanches the veins.
Distribution: most often on the legs, near veins; also on the anterior chest
Significance: often accompanies increased pressure in the superficial veins, as in varicose veins
Cherry angioma- color, size, shape pulsatility, effect of pressure, distribution, significance
Color: bright or ruby red, brownish with age
Size: 1-3 mm
Shape: round, flat, or sometimes raised, may be surrounded by a pale halo
Pulsatility: absent
Effect of pressure: may show partial blanching, especially if pressure is applied with the edge of a pinpoint
Distribution: trunk, also extremities
Significance: none; increase in size and numbers with aging
Petechiae/purpura- color, size, shape pulsatility, effect of pressure, distribution, significance
Color: deep red, reddish, purple
Size: petechia, 1-3 mm; purpura- larger
Shape: rounded, sometimes irregular; flat
Pulsatility: absent
Effect of pressure: none
Distribution: variable
Significance: blood outside the vessels; may suggest a bleeding disorder or if petechiae, emboli to skin
Ecchymosis- color, size, shape pulsatility, effect of pressure, distribution, significance
Color: purple, purplish blue, fading to green, yellow, brown
Size: variable, larger than petechiae
Shape: rounded, oval, or irregular; may have a central subq flat nodule (hematoma)
Pulsatility: absent
Effect of pressure: none
Distribution: variable
Significance: blood outside the vessels; often secondary to bruising or trauma; also seen in bleeding disorders
Squamous cell carcinoma
May develop in conjunction with an actinic keratosis; firm, red
Basal cell carcinoma
Initially translucent nodule; spreads; leaves a depressed center with a firm elevated border
