Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
86 Cards in this Set
- Front
- Back
|
What are the 6 functions of the skin?
|
1.Protect against injury, dessication
2. Role in the reg of body temp 3. Reception of sensory stimuli 4. Excretion from sweat glands 5. Secret of sebum, cerumen, milk, tears 6. Synth of Vit D |
|
|
What are the 4 different populations of cells that make up the stratified squamous epithelium (epidermis)?
|
1. Keratinocytes (90%)
2. Melanocytes 3. Langerhans cells (BM derived dendritic cells that fxn in Ag present) 4. Merkel cells (from neural crest, fxn as sensory cells for light touch) |
|
|
What are the 5 layers of the thick skin starting from the bottom?
|
1. Stratum basale
2. Stratum spinosum 3. Stratum granulosum 4. Stratum lucidum 5. Stratum corneum |
|
|
What are the 3 layers of the THIN skin starting from the bottom?
|
1. Stratum basale
2. Stratum spinosum 3. Stratum corneum No granulosum or lucidum |
|
|
Stratum basale
|
-single layer of cuboidal to columnar that are actively mitotic
-scattered Merkels and melanocytes -interdigitates w/ the dermis and is sep from it by basement membrane |
|
|
Stratum spinosum
|
-thickest layer and consists of keratinocytes referred to as prickle cells, mitotically active
-mitotically active layers of basale and spinosum can be referred to as the STRATUM MALPIGHI |
|
|
Stratum corneum
|
-numerous layers of flattened keratinized cells (squames) that eventually slough off the surface
|
|
|
What are the two layers of the dermis?
|
1. Papillary layer - loose CT layer
2. Reticular layer - deeper and denser |
|
|
Papillary layer of the dermis
|
-interdigitates w/ the epidermis forming dermal ridges (papillae) aka rete apparatus
-capillaries here involved in temp reg -some papillaie have Meissner's corpuscles also some have Krause end bulb |
|
|
Reticular layer of the dermis
|
-denser and less cellular
-has thick irreg bundles of collagen & coarse elastic fibers--> "Langer's lines" -Pacinian corps--> vibration and P -Ruffini corp--> tensile forces |
|
|
Sebaceous glands
|
-holocrine glands that are found over the surface of body (no palms, tosles and dorsum of feet)
-OILY |
|
|
Sweat (sudoriferous) glands
|
-eccrine glands all over the surface of the body (NO lips, ext ear canals, labia minora)
-most conc in thick skin of palms of the hands and soles of the feet -principally fxn in reg body temp |
|
|
Apocrine sweat glands
|
-found only in the axilla, areolae, and anal region
-mod apocrine glands include the ceruminous (wax) glands of the ear, glands of Moll in eyelids, and mammary glands |
|
|
Vellus hairs
|
-soft, fine, short and pale hairs
-ex eyelids |
|
|
Terminal hairs
|
-hard, large, coarse, long, dark
-ex scalp and eyebrows |
|
|
Panniculus adiposis
|
-adipose tissue of the hypodermis that is deep to the reticular layer
-contains deep part of hair follicles, some pacinian corps, and is the ori of smooth muscle fibers (arrector pili) |
|
|
Pannuculous carnosus
|
-largely vestigial in humans but:
-found in skin of the neck, face and scalps as platysma & muscles of facial expression -also in the scrotum (dartos), subareolar nipple muscle, and palmeris brevis |
|
|
Macule
|
-circumscribed, flat area of discoloration
-usually < 1 cm in diameter |
|
|
Papule
|
-elevated circumscribed, solid area
-usually < 1 cm in diameter |
|
|
Nodule
|
-elevated circumscribed, solid area
-usually > 1 cm in diameter |
|
|
Plaque
|
-elevated flat circumscribed area
-usually > 1 cm in diameter |
|
|
Vesicle
|
-fluid filled raised area
- < .5 cm in diameter |
|
|
Bulla
|
-fluid filled raised area
- > .5 cm in diameter (large vesicle) |
|
|
Blister
|
-common term for vesicle or bulla
|
|
|
Pustule
|
-discrete pus filled area
|
|
|
Scale
|
-dry, platelike (squamous) excrescence, usually as a result of a defect in keratinization
|
|
|
Lichenification
|
-thickened and rough skin characterized by prominent skin markings
-usually caused by chronic scratching |
|
|
Excoriation
|
-traumatic lesion characterized by disruption of the dermis causing a raw linear area
|
|
|
Furuncle
|
-boil
-localized pyogenic infx originating deep in the hair follicle |
|
|
Carbuncle
|
-a large boil
-the result of a confluence of multiple furuncles |
|
|
Parakeratosis
|
-keratinization characterized by retention of nuclei in the cells fo the stratum corneum
|
|
|
Dyskeratosis
|
-disorder of keratinization in which premature keratinization occurs in cells that have not reached the stratum corneum
|
|
|
Acanthosis
|
hyperplasia of the stratum spinosum
|
|
|
Acantholysis
|
-loss of cellular cohesion
-mainly involving the cells of the stratum spinosum |
|
|
Spongiosis
|
inflammatory intercellular edema of the epidermis
|
|
|
Lentigionous
|
-linear pattern of melanocyte proliferation w/in the epidermal basal layer
|
|
|
Erosion
|
discontinuity of the skin w/ partial los of the epidermis
|
|
|
Ulceration
|
-discontinuity of the skin w/ complete loss of the epidermis and often portions of the dermis and hypodermis
|
|
|
Papillomatosis
|
-hyperplasia of the papillary dermis w/ elongation and/or widening of the dermal papillae
|
|
|
Erythrasma
|
-chronic, superficial infx of intertrigionous areas of the skin by Cornebacterium spp (normal part of skin flora)
|
|
|
Pathogenesis of Erythrasma
|
-invade the upper 1/3 of stratum corneum
-***likes increased heat and humidity -production of porphyrin results in coral red flourescence of scales seen under Wood light |
|
|
Manifestations of Erythrasma
|
-well demarcated, brown-red macular patches
-skin is wrinkled w/ fine scales -commonly over inner thighs, legs, scrotum, and toe webs -com asympt but may be pruritic |
|
|
Complications of Erythrasma
|
-fatal septicemia in immunocomp pts
-infx endocarditis in vasc heart disease pts |
|
|
Impetigo
|
-contagious G + infx of superficial layers of the epidermis involving s. aureus or group A beta-hemolytic strep
-common in kids -nonbullous (most com) and bullous |
|
|
Ecthyma
|
-more severe form of impetigo that occurs in debilitated pts and pts w/ poorly controlled diabetes
|
|
|
Pathogenesis of Impetigo
|
-~1/3 of the pop is colonized in the anterior nares w/ S. aureus
-10% w/ S. aureus in the perineum, axillae, pharynx and hands |
|
|
Bullous Impetigo
|
-vesicle that develops into a superficial flaccid bulla < 1cm in diameter w/ little or no surrounding redness
-moist red base, often on face -NO regional lymphadenopathy |
|
|
Nonbullous impetigo
|
-red macule or papule that develops into a fragile vesicle or pustule
-rupture occurs and the lesion becomes a honey/yellow adherent crusted papule or plaque < 2cm, w/ minimal surrounding redness -Lymphadenopathy (node maybe tender) |
|
|
Complications of Impetigo
|
-acute glomerulonephritis can develop in those pts in which group A beta hemolytic streptococci are involved
|
|
|
Prognosis of impetigo
|
-lesions rarely heal spontaneously and new lesions often appear elsewhere on the body if they do
|
|
|
Folliculitis
|
-an inflam rxn in hair follicles com by S. aureus, but also by other bact, fungi, and overgrowth of parasites
-noninfx can result from follicular trauma or occlusion or may be simply idiopathic |
|
|
Impetigo of Brockhart or barbers itch
|
-most com superficial form
-caused by S. aureus -lesions are seen in bearded area often on the upper lip near the nose |
|
|
Hot tub folliculitis
|
-pseudomonas sp
-in pts that bathe in poorly maintained hot tubs |
|
|
Deep forms of folliculitis include?
|
-furncles and carbuncles
-typically on back of neck |
|
|
Manifestations of Folliculitis
|
-present w/ yellowish pustules on the base of hairs
-most often on the face, scalp, back, legs and arms |
|
|
Erysipelas
|
-superficial bact infx of skin that extends into the lymphatics
-historically by group A streptococci, but now more on legs w/ non-group A streptoccoci -primarily in adults |
|
|
Pathogenesis of Erysipelas
|
-bacteria through breaks in skin
-venous insuffic, statis ulcers, inflam dermatoses, dermatophyte infx all play a role -infx rapidly invades and spreads through lymph vessels*** |
|
|
Manifestations of Erysipelas
|
-painful, red, and edematous rash that is SHARPLY DEMARCATED
-lymphatic streaking (lymphangitis) and prominent adenopathy -systemic s/s: n/v, fever, malaise, etc |
|
|
Prognosis of Erysipelas
|
-generally benign
-fatal when assoc w/ bacteremia in young, elderly or immunocomp |
|
|
Cellulitis
|
-acute spreading infx of the dermis and subcut tissues--> pain, red, edema
-males esp over age 50 |
|
|
Pathogenesis of Cellulitis
|
-group A and B streptococci, S. aureus, H. flu, halophilic Vibrio (costal areas)
-thru break in skin and rapidly spread to involve the subcut spaces in addition to the dermis |
|
|
Manifestations of cellulitis****
|
-tender w/ erythema and edema, warm to touch
-margins are indistinct which helps diff from erysipelas*** -lymph streaking and lymphadenopathy may be present |
|
|
Prognosis of cellulitis
|
-generally good, but complications such as bacteremias, thrombophlebitis, and meningitis, esp in kids w/ facial cellulitis
|
|
|
Common warts (verruca vulgaris)
|
-round or irreg shaped firm growths usually w/ a rough surface that are gray, yellow, or brown
-freq on knees, face, fingers, around the nails |
|
|
Plantar warts
|
-develop on the sole of foot
-usually flattened by walking -maybe pain in weight bearing areas |
|
|
Filiform warts
|
-long, narrow, small growths that appear on the eyelids, face, neck or lips
|
|
|
Flat warts (verruca plana)
|
common in kids and young adults
-appear in groups as smooth yellow-brown, pink, or flesh colored spots -most freq on face and tops of hands |
|
|
Genital warts (condylomata acuminata)
|
-on genitals
-irregular bumpy growths often w/ a cauliflower like surface |
|
|
Molluscum contagiosum
|
-infx of the skin by the largest DNA pox virus
-bimodal age distribution: in kids trans from nonsex skin contact adn adult is through STD |
|
|
Pathogenesis of Molluscum contagiosum
|
-virus ONLY infx the epidermis
-initial infx occurs in the basal layer & stays latent for 6 months -rep and formation of new viral particles, w/ spinous and granular layers involved |
|
|
Manifestations of Molluscum contagiosum
|
-single or multiple, discrete papules, 2-6 mm across
-central pit w/ a white curd like core -epidermal hyperplasia forming a cup like structure filled w/ molluscum bodies (Henderson-Patterson bodies) large eosino-baso IC iclusions |
|
|
Prognosis of Molluscum contagiosum
|
-generally lasts 2-4 wks and disease usually resolves in 2-4 years
-recurrence can occur |
|
|
Fungal skin infx
|
-moist areas of the body: btwn toes, in the axilla, genital area, under breasts
-superficial infx typically involve ONLY stratum corneum, not deeper |
|
|
Dermatophytes
|
3 main genera:
1. Trichophyton 2. Microsporium 3. Epidermophyton -result in skin infx know as "ringworm" and named tinea in accordance to location |
|
|
Tinea pedis (athlete's foot)
|
-between toes
-either dry w/ scaling or moist w/ maceration, peeling, and fissuring of the toe webs |
|
|
Moccasin type of Tinea Pedis
|
-soles, high on heels, and lateral borders of the feet
-lesions are red, w/ hyperkeratosis and fine white scaling -usually both feet and becomes chronic w/ periodic exacerbation |
|
|
Inflammatory/Bullous type of Tinea Pedis
|
-blisters filled w/ clear fluid form on sole, instep, between toes
-2ndary infx w/ bact shows pus |
|
|
Ulcerative type of Tinea Pedis
|
-extension of infx from between the toes onto dorsum and plantar foot-->macerated and undergo ulceration
|
|
|
Tinea cruris (jock itch)
|
-large well demarcated plaques of scaling dull/red/brown skin w/ possible papules or pustules at margins
-groin area, thighs or buttock -USUALLY NOT SCROTUM |
|
|
Tinea corporis (body ringworm)
|
-annular type lesions--> red circles w/ raised edges and central clearing
-can become chronic -2nd type is the vesicular lesion in which vesicles and pustules from behind advancing border -warmer climates |
|
|
Tinea capitus - Dry type
|
-lesion may be dry and scaly resembling dandruff of the scalp, psoriasis, or lichen planus
|
|
|
Tinea capitus - Black dot type
|
-dry, scaly, red w/ black dots
-fungal structures microscopically w/in endothrix (infx hair shaft) -chronic--> to adulthood |
|
|
Tinea capitus - Kerion
|
-highly inflam lesions that are edematous, oozing, and crusting
-scalp--> hair loss maybe permanent due to scarring |
|
|
Tinea capitus - Favus
|
-formation of a solid crus which may spread to cover the whole scalp
-scalp has a mousy odor and infx may spread to other parts of body -hair loss maybe permanent due to scarring |
|
|
Cutaneous Candidiasis
|
-diaper rash in infants
-pts w/ diabetes and obese -of intertriginous areas present w/ erythema, splitting, and maceration w/ soreness and pruritic symptoms -irregular margins w/ surrounding papules and pustules |
|
|
Tinea versicolor
|
-superficial skin infx by yeast malassezia furfur
-macules and patches on trunk, shoulders, upper neck and limbs -dark lesions on light, light on dark -chronic and recurrence is common |
