Intro Flashcards
Primary Skin lesion
- Macule
- Papule
- Nodule
- Plaque
- Tumor
- Pustule
- Wheal
- Vesicle
- Bulla
Secondary Skin lesion
(Evolutionary)
- Scale
- Crust
- Scar
- Ulcer
- Excoriation
- Lichenification
- Hyperpigmentation
- Hyperkaratosis
- Epidermal collarette
Alopecia def
Decrease in amount of hair/ absence of hair
Bulla def
Large vesicle (an intraepidermal or subepidermal accumulation of serous fluid)
Comedo def
pl: comedones
Accumulatin of keratin and dried sebum in hair follicle
Crust def
Dried exudate for secretion +/- epithelial or bacterial debris
Dermatitis def
Inflammation of the skin
Dermatosis def
Abnormal conditin or disease of the skin
Epidermis def & layers
Outermost nonvascular layer of skin
five layers (outside in):
- Stratum corneum
- Stratum lucidem
- Stratum granulosum
- Stratum spinosum
- Stratum basale
Erythema def
Redness produced by capillary congestion
Excoriation def
Superficial erosion or ulcer
(implies scratching or abrasion)
Hyperkeratosis def
Orthokeratosis/parakeratosis
Thickening of stratum corneum due to inc number deratinized cells
(inc production/dec loss)
Orthokeratosis (loss of nucleus in norm fashion) vs parakeratosis
Keratinocyte
Cell of epidermis
Lichenification def
Thickening of skin with exaggeration of normal markings
- acanthosis
- hyperkeratosis
- dermal thickening
Macule def
Circumscribed flat change in skin color
(pale, hyperpigmented or erythematous)
Nodule def
Large papule, often extends into dermis
Papule def
Circumscribed elevation of skin less than 1 cm in diameter
Plaque def
Raised flattopped lesion
Pustule def
Circumscribed epidermal or dermal accumulation of purulent exudate
Pyoderma def
Purulent dermatitis
Scale def
Flake of abnormal or compacted epithelial cells
Seborrhea def
- A functional distrubance of sebaceous glands or of lipid metabolism of the epidermis.
- Accompanied by abnormal keratinization
Stratum basale
- Innermost layer of epidermis composed of columnar cells arranged on a basement membrane.
- Germinative layer of the skin
Stratum corneum
Outermost layer of epidermis composed of dead keratinized epidermal cells
Stratum granulosum
Layer of epidermis composed of flattened cells with pyknotic nuclei and keratin granules
Tumor def
- Swelling or enlargement
- Usually neoplastic
Ulcer def
- Loss of substance on a cutaneous surface exposing inner layers or tissues
- May imply full thickness loss of epidermis
Vesicle def
A circumscribed elevation of epidermis caused by accumulation of clear fluid within or beneath the epidermis
Wheal def
- A HIVE
- Sharply circumscribed skin elevation produced by edema of the superficial dermis
Skin scraping
- cheap and easy
- clip hair, apply mineral oil, scrape stratum corneum with dull scalpel blade
- low light, 100X magnification
Direct Examination of Hair and Scales
- Hair shaft morphology
- Examination for superficial fungi
Impression smears/aspirations
- Nodules/intact pustules/vesicles: aspirate with 22-25g needles
- Exudative lesions: touched, swabbed, or lightly scraped, add 1 drop KOH
Biopsy
- May require sedation/anesthesia
- no surgical prep to preserve crusts/scabs
Intradermal skin test
- dilute antigen injected intradermally
- response read 15-30 minutes after injection, saline is control
