Clinical-Pathologic Correlation of Lesions Flashcards
distribution
regions of the skin affected by the lesions
solitary, multifocal, generalized
configuration
spatial relationship between individual lesions
annular
circular
serpiginous/serpentine
snake-like; coalesce to form serpent-like patterns
targetoid
bulls-eye
primary lesions
changes in color, appearance, or texture
can be congenital or acquired
secondary lesions
changes in skin that result from primary skin lesions
can be caused by progression (ex. pustule –> epidermal collarette) or manipulation (scratching and biting)
macules
changes in color (depigmentation, hyperpigmentation, or redness) without elevation or depression of the surface
what causes macules to be red
hemorrhages (petechiations)
what causes depigmentation/leukoderma
interface dermatitis
immune mediated attacks on keratinocytes leading to single cell necrosis –> release of melanocytes into the dermis –> pigmentary incontinence
papules
circumscribed, solid elevation of the skin involving the epidermis and dermis (with domed surface)
accumulation of inflammatory cells underneath the surface
plaques
large, flat topped circumscribed elevation of the skin
often a coalescence of papules
nodules
larger or solid
deep mass in dermal or subcutaneous tissue with visible and palpable elevation of the skin
nodular to diffuse dermatitis
inflammation leading to the formation of papules +/- masses that expand
what causes nodular to diffuse dermatitis
infectious
immune mediated
idiopathic
neoplastic populations of the skin
can expand the skin (benign) or infiltrate and replace the skin (malignant)
can be primary or metastatic
wheals
hives; well-circumscribed, flat topped, firm elevation of the skin with a well demarcated, palpable margin
pits with pressure
associated with urticaria
urticaria
skin reaction leading to wheals
vesicles & bullae
circumscribed elevation of the epidermis containing serous fluid either within the epidermis or at the dermo-epidermal junction
vesicles < 1 cm
bullae > 1 cm
what do vesicles form
rupture to form erosions or ulcerations
intraepidermal vesicles
formation of vesicles within the epidermis
caused by:
- spongiosis
- acantholysis
- intracellular edema
- apoptosis
subepidermal vesicles
formation of vesicles at the dermo-epidermal junction (BMZ)
primary subepidermal vesicles
result from damaged BMZ causing the epidermis to no longer be attached to underlying dermis
complete detachment occurs
secondary subepidermal vesicles
results from damaged basal cells leading to necrosis of basal cells and superficial keratinocytes –> vacuolization or apoptosis
pustules
circumscribed elevation of the epidermis containing purulent material (pus - fluid and cells)
epidermal collarettes
narrow rim of loosened stratum corneum that hangs over the peripheral edge of a circumscribed skin lesion
occurs secondary to chronic pustules
can become hyperpigmented
erosions
superficial denudation of the skin confined to the epidermis
- does NOT cross the BMZ
- basal cell layer remains intact
- does NOT bleed
- progresses to ulcerations
ulceration
defect of the skin extending through the dermo-epidermal junction (BMZ) into the dermis
- actively bleeds
- can be caused by vascular damage leading to triangular regions of necrosis and ulcerations
excoriations
erosions and ulcers produced by self-trauma
surrounding tissues show signs of chronic irritation
what are signs of chronic irritation
- acanthosis (epidermal hyperplasia)
- rete peg formation
- hypergranulosis
- compact hyperkeratosis
scale
accumulated fragments of dead, cornified epidermal cells (stratum corneum)
nonadherent
what conditions result in scale
- ichthyosis
- zinc responsive dermatosis
crusts
accumulated fragments of cornified epidermal cells (scale) + dried residue of serum, pus
what does crust indicate
inflammation in the superficial dermis
lichenification
thickening of the skin; usually with hyperpigmentation and increased prominence of normal surface epidermal architecture
what does lichenification indicate
chronic self trauma
alopecia
decreased number of hair shafts per given area of body surface leading to partial or complete loss of hair coat
what are possible causes of alopecia
- congenital malformation of the follicles
- breaking of hair shafts
- cyclic arrest of follicular cycle
- follicular destruction
- follicular atrophy