Derm Histo Flashcards
abnormal, premature keratinization in cells below s. granulosum;
dyskeratosis
loss of intercellular connections b/w keratinocytes
acanthoLYSIS
epidermal intercellular edema
- fluid b/w cells –> clear spaces b/w; clear separation
SPONGIOsis
diffuse epidermal hyperplasia
(thickening of epidermis –> seeing elongation of rete pegs)
acanTHOSIS
d/c of the skin w/ INCOMPLETE loss of epidermis
(layer of skin is missing)
erosion
d/c of skin w/ COMPLETE loss of epidermis & often part of dermis/subcutis
(a deeper lesion)
ulceration
thickening of stratum corneum by abnormal keratin
hyperkeratosis
retention of nuclei in stratum corneum;
indication fo something irritating the skin but can’t clear the nuclei in time
PARAkeratosis
(*won’t be asked bc it’s so subtle & nonspecific)
Which ACUTE dermatosis?
- Sparse superficial perivascular infiltrate of mononuclear cells, neutrophils, and esoinophils
-
Dermal edema: widely spaced collagen bundles
- Angioedema
- Dilated superficial lymphatic channels
URTICARIA
Which acute dermatosis?
- spongiosis of the epidermis –>
- intraepidermal vesicles or blister formation
- Superficial perivascular lymphocytic infiltrate, dermal edema, eosinophils
Acute eczematous dermatitis
Which acute dermatosis?
- lymphocytes accumulate along dermoepidermal junction; where they are assoc w/ degenerating & necrotic keratinocytes
- Superficial perivasc lymphocytic infiltrate w/ dermal edema
- No chronic changes (i.e. epidermal atrophy, hyperplasia or hyperkeratosis)
ERYTHEMA MULTIFORME;
- lymphocytes accumulate along dermoepidermal junction; where they are assoc w/ degenerating & necrotic keratinocytes
- Superficial perivasc lymphocytic infiltrate w/ dermal edema
- No chronic changes (i.e. epidermal atrophy, hyperplasia or hyperkeratosis)
which chronic dermatosis?
- acanthosis (epidermal thickening) w/ downward elongations of rete ridges;
- thinned or absent granular layer w/ extensive parakeratosis
- Thin suprapapillary plates (epi layer overlying tips of dermal papillae)
- *Munro microabscesses: aggregates of neutrophils w/in parakeratotic scale
PSORIASIS
(assoc w/ MUNRO MICROABSCESSES)
which chronic dermatosis?
- interface dermatitis (dense lichenoid lymphocytic infiltrate along dermoepidermal jxn assoc. w/ degenerated & necrotic keratinocytes)
- Saw toothing (angulated zig-zag contour of the dermoepidermal interface; border changes; “hinting”)
- Colloid or Civate bodies (anucleate, necrotic keratinocytes in papillary dermis)
- Chronic changes (epidermal hyperplasia or atrophy; hypergranulosis & hyperkeratosis)
LICHEN PLANUS
(histo: bandlike infiltrate of lymphocytes at dermal-epidermal jxn & saw-tooth rete ridges)
which chronic dermatosis?
- acantholysis (common histo feature); blisters form at diff’t levels w/in skin (suprabasal is most common)
- Superficial dermal inflammatory infiltrate of lymphocytes, histiocytes, eosinophils
Pemphigoid vulgaris
(contains antibodies against desmoglein 3 – direct immunofluorescence: lesional skin shows characteristic netlike pattern of intercellular IgG deposits
which chronic dermatosis?
- subepidermal nonacantholytic blister; *eosinophils present in blister;
- Superficial and deep perivasc infiltrate w/ lymphocytes, eosinophils, neutrophils
BULLOUS PEMPHIGOID
direct immunofluorescence → LINEAR deposition of immunoglobulin & complement at dermo-epidermal jxn (ribbon candy pattern)
which chronic dermatolosis?
- early lesions w/ fibrin & neutrophils accumulating at tips of dermal papillae → microabscesses → w/ minute foci of dermo-epidermal separations (microblisters)
- Microblisters coalesce → form true subepidermal blisters
DERMATITIS HERPETIFORMIS:
- direct immunofluorescence: granular deposits of IgA at the tops of dermal papillae; antigliadin antibodies to dietary gluten
- Cross react to components of anchoring fibrils in skin
which chronic dermatosis?
- lesions show widening of CT septa due to edema, fibrin, neutrophils, lymphocytes, histiocytes, giant cells, occasional eosinophils, & septal fibrosis; typically NO VASCULITIS
ERYTHEMA NODOSUM
which viral infection?
- epidermal hyperplasia;
- koliocytosis (viral cytopathic effect);
- cytoplasmic vacuolization and pale halos surrounding infected nuclei;
- coarse keratohyaline granules
VERRUCAE (virus);
- papillar projections, dense granular cell layer*
- coarse keratohyaline granules*
which derm path?
most superficial nevus cells are immature, larger, and melanin-producing; deeper cells are mature, smaller, fusiform, and do not produce pigment
MELANOCYTIC NEVI
- Junctional nevi: (flat) nests of melanocytes along dermo-epidermal jxn
- Compound n.: (*elevated) nests of melanocytes along dermo-epi jxn & dermis
- Dermal n.: (*elevated) nests of melanocytes in dermis only
which derm path?
- nevus nests are large and fuse w/ each other
- Melanocytic atypia w/ irregular hyperchromatic nuclei
- Lymphocytic infiltrate in the upper dermis
- Linear dermal fibrosis around the rete ridges
DYSPLASTIC NEVI
which type of malignant melanoma growth?
melanoma cells tend to grow HORIZONTALLY along epidermis & superficial dermis; no metastatic potential
Radial growth phase
which type of malignant melanoma growth?
melanoma cells grow vertically in deeper dermis w/ no maturation and acquire metastatic potential
Vertical growth phase
type of nevi?
large cells w/ large irregular nuclei;
clumped chromatin & prominent red nucleoli growing as individual cells or poorly defined nests at all levels of epidermis (radial growth) and dermis (vertical growth)
MALIGNANT MELANOMA
which derm path?
- Exophytic, well-demarcated
- Composed of sheets of basal epidermal cells w/ melanin pigmentation and hyperkeratosis in the form of keratin filled cysts (horn cysts)
- Can occur in large numbers as part of paraneoplastic syndrome (Leser-Trelat sign); most commonly assoc w/ adenocarcinoma of stomach
- Exophytic: tending to grow outward beyond the surface epithelium from which it originated
Seborrheic keratosis
which derm path?
(microscopically) fibrovascular cores covered by benign squamous epithelium
Fibroepithelial polyp
which derm path?
- Invaginations and cystic expansion of epidermis, filled w/ keratin and lipid debris
- Creates intense inflammation if ruptured
Epithelial cysts (Wen)
which derm path?
- Parakeratosis; cytologic atypia of lower most epidermal cell layer, assoc. w/ hypertrophic and atrophic epidermis
- Elastosis (blue-gray elastic fibers) in the upper dermis, resulting from sun-damaged fibroblasts
ACTINIC KERATOSIS
which derm path?
- atypical enlarged hyperchromatic cells at all levels of epidermis
- Confined w/in epidermis; in situ - or invading through basement membrane into dermis (invasive)
Squamous cell carcinoma
which derm path?
- tumor cells resemble basal keratinocytes;
- Tumor islands show palisading peripherally (long axes of the cells is in parallel alignment)
BASAL CELL CARCINOMA
which derm path?
- benign dermal neoplasm of fibroblasts and histiocytes
- Benign, spindle-shaped fibroblasts arranged in well-defined mass in mid-dermis –> mixed w/ variable amounts of foamy histiocytes
- Overlying epidermal hyperplasia
Benign fibrous histiocytoma (Dermatofibroma)
which derm path?
- Morph: cellular neoplasm, fibroblasts arranged in storifom pattern;
- Thin overlying epidermis
- Extension into subcutaneous tissue
Dermatofibrosarcoma protuberans
