Dermatology - Classifications Flashcards
Bulla
A superficial, well circumscribed raised fluid filled lesion greater than 0.5 cm in diameter ex. bullous pemphigoid, pemphigus, dermititis herpetiformis
burrow
a subcutaneous linear track made by a parasite ex. scabies
crust
a slightly raised lesion with irregular border and variable color resulting from dried blood, serum, or other exudate ex. scab from an abrasion, impetigo
ecchymosis
a flat non blanching red-purple-blue lesion that results from extravasation of RBCs into the skin. Non-palpable >5 mm ex. trauma, long term steroid use
erosion
- Loss of superficial layers of upper epidermis by wearing away from friction or pressure
- Heals without scarring
- Red, oozes
ex. rupture of herpes simplex blister
excoriation
Skin abrasions, usually superficial, due to scratching of the skin ex. scratching assoc with pruritis
fissures
Sharply-defined, linear or wedge-shaped tears in the epidermis with abrupt walls
ex. cracks seen in athlete’s foot
keloid
irregular raised lesion resulting from hypertrophied scar tissue ex. seen with burns, African Americans are more prone
lichenification
a thickening of the skin with an increase in skin markings resulting from chronic irritation and rubbing ex. atopic dematitis
macule
a circumscribed nonpalpable discoloration of the skin less than 1 cm in diameter ex. freckles, rubella, petechiae
Nodule
A palpable, solid lesion, > 1 cm in diameter. Usually found in dermal or subcutaneous tissue; may be above, level with, or below the skin surface ex. erythema nodosum, gouty tophi
papule
a solid elevated lesion less than 1 cm in diameter
ex. acne, warts, insect bites
patch
A circumscribed area of discoloration, > 1 cm, without elevation or depression
ex. vitiligo
petechiae
a flat non blanching red-purple-blue lesion that results from extravasation of RBCs into the skin.
Non-palpable <3 mm
ex. DIC, ITP, SLE, meningococcemia
Plaque
A well-circumscribed, elevated, superficial, solid lesion, > 1 cm in diameter. May be formed from confluent papules
ex. psoriasis, discoid lupus erythematosus, actinic keratosis
purpura
- Non-blanching, violaceous (red/purple) discoloration of the skin
- Due to blood that has extravasated outside of vessel walls
- palpable or non-palpable
ex. henoch-schonlein purpura, TTP</p>
pustule
A small (< 1 cm in diameter), circumscribed superficial elevation of the skin that is filled with purulent material. Can also be described as filled with pus ex. acne, impetigo
scales
Visible shedding of the stratum corneum (epidermal layer)
ex. psoriasis, dandruff
scar
Final stage of healing which involved the deeper dermis
telangiectasia
dilation of capillaries resulting in red, irregular, clustered lines that blanch.
Ex. scleroderma, osler-weber-rendu disease, cirrhosis
tumor
a solid palpable circumscribed lesion greater than 2 cm in diameter
ex. lipoma
ulcer
Localized defect of irregular size and shape, loss of epidermis and some dermis; scars
ex. decubitis ulcers, primary lesion of syphilis, venous stasis ulcer
Vesicle
A small, superficial, circumscribed elevation of the skin, < 0.5 cm, contains serous fluid
ex. herpes simplex, varicella
Wheal
Transient, circumscribed, elevated papules or plaques, often with erythematous borders and pale centers
ex. uticaria, allergic reaction to injections or insect bites
Discrete
Each lesion is easily separated from others
Confluent
Edges of the lesions blend into one another
Isolated
just one lesion in the area
Scattered
Lesions are discrete, multiple and distributed in no discernible pattern
Grouped
Lesions appear close together with normal skin between groups
Dermatomal
Distributed in one spinal nerve or spinal nerve equivalent branch
Annular
ring like shape
polycyclic
shape made up of tangential rings
Arcuate
arc shaped
Serpiginous
Shape like a snake
Iris/Target
Shaped like a bulls eye
Reticulate
Net like pattern
Glaborus
Shiny and smooth surface; bald
Atrophy
Thinning or depression of skin due to reduction of underlying tissue
Sclerosis
Hardening or induration of the skin caused by an increase in collagen, other connective tissue components (mucin), edema, cellular infiltration
Necrosis
Death of skin tissue
Comedone
Darkened plug of sebum and keratin; occludes pilosebaceous follicles
Open: blackhead
Closed: whitehead
Cyst
Encapsulated, raised lesion filled with solid or liquid material; often fluctuant
Elliptical excision technique
Anesthetize area after marking; excise in elliptical shape with length 3x longer than width; undermine edges for easier suture closure without puckers
Shave biopsy/excision technique
Anesthetize the area making a wheal surrounding the lesion; excise in a scooping manner to get underlying dermis/SC, ensuring entire lesion is excised
Punch biopsy
anesthetize the area; place punch 90 degrees from skin and rotate with downward pressure until SC is reached; lift gently and cut bottom
KOH
Scrape the edge of scaly lesion onto glass slide; add 1-2 drops of KOH onto slide; +/- heat for few seconds; look for spores/hyphae/budding yeast to confirm fungal infection
Tzanck smear
Unroof an intact vesicle at the base and collect fluid onto slide or swab. Multinucleated giant cells confirm herpes/varicella infection
Diascopy/Dermoscopy
Dermatoscope to skin to note algorithmic patterns when magnified to identify suspicious lesions
Wood’s light
Shine light onto skin areas to confirm; Coral/pink-erythrasma Pale blue-Pseudomonas Yellow/green-Microsporum Green/gold-tinea versicolor White-vitiligo
