Intro Flashcards
guttate
drop like
gyrate
twisted spiral
nail matrix
produces major part of nail plate
nail bed
contains blood vessels, lymphatics
consists of epidermis and dermis
Anagen Phase growth factors, hormones, stress,
immunologic and physical injury
(growth) – hairs with pigmented malleable proximal ends
* extremely sensitive to drugs,
Catagen Phase
(transition) – duration is usually a few weeks
Telogen Phase
(reset) hair falling out; club hairs with depigmented rounded proximal ends
Macule
A circumscribed area of change in normal skin color without elevation or depression. Generally considered less than 0.5-1.0 cm, which may be brown, blue, red, or hypopigmented
Ex: vitiligo, tinea versicolor, Lentigo, freckles, mongolian spot
Patch
large macule equal to or greater than 0.5 -1.0cm across. Patches may have some subtle surface change, such as a fine scale or wrinkling, but although the consistency of the surface is changed, the lesion itself is not palpable.
Ex: sunburn, melasma, port wine stain
Papule
An elevated solid lesion, generally considered less than 0.5cm in diameter, is palpable, color varies
Ex: warts, lichen planus, acne, molluscum contagiosum
Plaque
A circumscribed, elevated, superficial, solid lesion more than 0.5cm in diameter (often formed by the confluence of papules)
Ex: psoriasis, pityriasis rosea, tinea corporis, secondary syphilis
acuminate
pointed
fili-form
threadlike
bulla
A circumscribed collection of free fluid greater than 0.5cm in diameter
Ex: drug eruption, contact dermatitis
nodule
A circumscribed, elevated, solid lesion more than 0.5cm in diameter; a large nodule is referred to as a tumor
Ex: warts, erythema nodosom, lypoma, lymphoma, BCC, SCC
scales
excess dead skin, flakes of stratum corneum
crust
dried serum, blood o purulent exudate dries on the skin surface
erosion vs
ulcer
epidermis, no scarring
involves dermis, will scar
Desquamation
skin coming off in scales
Pityriasiform
branny powdery scale
Sensitization Phase
– a hapten (low molecular weight substance) penetrates into dermis and combines with epidermal protein; a message is sent to T Cell precursors, and sensitized T Cells are formed.
Elicitation Phase
– on reexposure to the antigen-protein complex, sensitized T Cells release lymphokines which recruit inflammatory cells causing inflammation
type I hypersensitivity
IgE
urticaria, angioedema
type II
Drug + Cytotoxic Ab cause lysis of cells such as platelets or leukocytes
Petechiae due to thrombocytopenic purpura, drug-induced pemphigus