Derm Path & Definitions Flashcards
Freckle (ephelis)
Inc melanin pigmentation along basal layer of epidermis (stratum basalis)
NO acanthosis (thickening) of epidermis NO melanocytic nest formation
Lentigo
Inc melanin pigmentation along basal layer of epidermis (basalis)
WITH acanthosis (thickening) of epidermis WITH elongation of rete ridges INC melanin pigmentation at base of rete ridges
Vitiligo
Hypopigmented patched skin - auto-immune
ABSENCE of melanocytes
Rule out tinea versicolor (M. furfur)
Junctional Melanocytic Nevus (benign mole)
Nests of melanocytes at derma-epidermal junction only
New in adults = worrisome
Intradermal Melanocytic Nevus (benign mole)
Nests of melanocytes in dermis only
Compound Melanocytic Nevus (benign mole)
Nests of melanocytes at BOTH derma-epidermal junction and in dermis
Blue Melanocytic Nevus (benign mole)
Spindle-shaped melanocytes usually w/ lots of melanin pigmentation usually in dermis
Dysplastic Melanocytic Nevus (benign mole)
Nests of melanocytes at dermo-epidermal junction stretching from rete ridge to adjoining rete ridge, surrounding lamellar fibrosis and peri-vascular chronic inflammation
Halo Melanocytic Nevus (benign mole)
Halo around nevus
Mod–> severe infiltration of lymphocytes that are attacking the melanocytes = auto-immune
Possibly malignant
Most malignant melanomas arise…
de novo
Dysplastic nevus syndrome
Multiple pigmented lesion of trunk, chets abdomen
All a little bit irregular
Hyperkeratosis
Orthokeratotic thickening of stratum corneum
Orthokeratosis
Normal state of keratinocytes in most superficial layer of epidermis = NO NUCLEI IN KERATINOCYTES
Acanthosis
Thickening of all 4-5 layers of the epidermis
Exocytosis
Extension of any leukocyte inflammatory cells into epidermis
Malignant melanoma
Malignant neoplasm of cells showing melanocytic differentiation
S-100+
HMB-45+
Begins de novo w/ atypical nested proliferation at D-E junction w/ PAGETOID GROWTH –> dermis
Most important factor determining melanoma mets
Thickness/depth of invasion
Must be <0.76mm to be unlikely to met
Breslow’s Level
Greatest neoplastic depth of invasion in millimeters from granular layer of epidermis
Clark’s Level
I - in situ (epidermis only, should not met)
II - invading but not filling papillary dermis
III - invading and filling papillary dermis
IV - invading into reticular dermis
V - invading into adipose tissue of cubcutis
Superficial spreading malignant melanoma
Horizontal growth
Nodular malignant melanoma
Vertical growth
Aral-Lentiginous malignant melanoma
Occurs on acral skin (hands/feet)
Neurotopic
Spindle cell differentiation - malignant form of blue melanocyitc nevus - usually does not show epidermal involvement
Seborrheic Keratosis
Benign proliferations of keratinocytes
“Stuck-on” lesions
Spongiosis
Edema fluid separating keratinocytes from each other in epidermis
Acantholysis
Breakdown of normal desmosomal attachments b/w keratinocytes in epidermis
Parakeratosis
Abnormal state of keratinocytes having nuclei in stratum corneum - ALWAYS ABNORMAL IN KERATINIZING SKIN
Hypergranulosis
Thickening of stratum granulosum
Koilocytosis
Peri-nuclear clearing around nulei in keratinocytes - usually indicative of HPV
Skin vs. squamous mucosa
No nuclei in stratum corneum in skin vs. keratinocytes ALWAYS having nuclei in non-keratinizing squamous mucosa
Dyskeratosis
Abnormal kerainization of keratinocytes usually individually below the layer of the stratum granulosum
Lentigo malinga/Hutchinson’s freckle
Elderly, sun-exposed area
1 place for melanoma metastasis
Liver
MOA of corticosteroids
Inc lipocortins –> Inhibits phospholipase A2 –> Less arachadonic acid
anti-inflammatory, less edema, less erythema, less pruritis, less plaque
Corticosteroid abs
Minimal percutaneous
- LT occlusion inc
- Inflammation inc
- Genitals abs 30%!!!
Low potency corticosteroids*
Low (VII) - hydro - dexa - methylprednisolone, prednisolone Tx - atopic, seborrheic, psoriasis
Intermediate
- Fluticasone
High potency corticosteroids*
High (class I) - Betamethasone - Clobetasol - Halobestasol Tx - Pemphigus, vitiligo, keloids, hypertrophic scars, acne cysts
Corticosteroids toxicity
- Suppression of Pituitary-adrenal axis –> Cushing
- Growth retardation in kids
Topical
- atrophy
- rosacea
- telangectasia
- striae
DOC for psoriasis*
- Topical steroids 2x/d*
- hands - more potent, less continuous (5-10%)
Psoriasis causes & epidemiology*
SMOKING, climate, stress
20-30 & 50-60
Whites > Blacks
KNUCKLES, elbows, knees, scalp
Drug causes
- Lithium
- BBs
- anti-malarials
- SYSTEMIC steroids
Tazarotene MOA
Modulates differentiation and proliferation of epithelial cells –> antiinflammatory and anti-proliferative
Tazarotene SE*
NOT IN PREGNANCY
Calcipotriene
D3 derivative
Extremely effective - 1-2wks
Coal Tar
ONLY in-combination w/ other therapies for psoriasis - UVB therapy
Acitretin*
Vit A retinoid - pustular psoriasis
Tx 3-6mo
NOT IN PREGNANCY or 3 YEARS AFTER
Etanercept
Dimeric fusion protein Binds TNF receptor
SubQ a couple times a month
SE - life-threatening infections & sepsis
Adalimumab
Human IgG1 TNF Ab –> downreg of MO & T-cell fxn
Psoriatic arthritis
SE - latent TB, opportunistic infections
Infliximab
Chimeric IgG1 TNF Ab –> downreg of MO & T-cell fxn
SE - demyelinating = CI in MS
PUVA (Psoralens and UVA)
Psoralens - makes them more light sensitive (320-400nm)
Methorexate MOA
Mod-severe psoriasis
Inhibits dihydrofolate reductase –> inhibits DNA synthesis
MTX dosing & SE
Oral triple-dose - q12hrs for 26hrs
BM SUPPRESSION –> agranulocytosis/pancytopenia
- Dec dose for several months at a time
- Rescue = LEUCOVORIN
MTX toxicities*
CI - pregnancy, hepatic
TMP-SMX, Probenecid, salicylates, NSAIDs
Anti-trichogenic
Inhibits ornithine decarboxylase
Repigmentation - tx of vitiligo
Trioxsalen & Methoxsalen (Psoralens + UVA)
Penicillin Rxn
Utricarial - exanthematous –> stop, tx w/ anti-histamine, steroids
OCs & sulfa rxns
Erythema nodosum - tender, subq nodules, PRE-TIBIAL
Self-limiting - STOP offending agent
Anti-convulsants, Barbs, sulfa rxns
Erythema multiforme - Maculopapular, bullous, “target lesions”
#1 = HSV TEN or SJ syndrome
Acral Skin
Normal thick skin of palms and soles w/ all five layers
Skin other than acral
Other than palm and soles w/ 4 layers - NO stratum lucidum
Vesicles
Cystic area in epidermis b/c spongiosis and/or acantholysis in epidermis (intradermal vs. subdermal)
Intraepidermal bulla
At least the stratum basal is remains attached to the basement membrane and dermis
Subepidermal bulla
ENTIRE epidermis is detached from dermis
Erosion
complete loss of epidermis
Exfoliative dermatosis/dermatitis
Some particular skin disease whose major feature is loss of epidermis from dermis either locally or systemically
Apoptotic necrosis of keratinocytes
Focal necrosis of individual keratinocytes in epidermis usually seen in the classic differential diagnosis:
- Erythema multiforme
- TEN
- Fixed Drug Eruption
- Phototoxic Dermatitis
- GVHD
Pemphigus vulgaris
Pemphigus = intraepidermal Cytotoxic Abs (Type II HS) LINEAR deposition of IgG on desmosomes = acantholysis FLACCID bulla Eosionphils
Bollous pemphigoid
Pemphigoid = SUBepidermal
LINEAR IgG to BM/hemidemisomes
TENSE bulla
Eosinophils
Dermatitis Herpetiformis
Celiac disease
IgA deposition in papillary dermis
Neutrophils in papillary dermis
Porphyria
Porphyria cutanea tarda
Inc porphrin excretion - illuminated w/ woods lamp
Epidermolysis bullosa
Congenital abnormalities w/ BM - epidermis cleaves from dermis w/ little trauma
Psoriasis
Neutrophils in paraketatotic scale
