intro derm (quiz 1)

*= quiz 1

*what is the thickness of the epidermis

*what is the thickness of the epidermis

0.05mm-1.5mm

*characteristics of the epidermis

keratinized, stratified squamous, avascular

*what are the layers of the epidermis (bottom up)

stratum basale, stratum spinosum, stratum granulosum, stratum lucidum (optional), stratum cornuem

*how many layers in thick skin

5

*how many layers in thin skin

4

*keratinocytes function

make and store keratin, makes nails hard and provides water resistance to hair, skin, nails

*cells in stratum basale

merkel cells, melanocytes (NO, KERATINOCYTES)

*merkel cells function

sensory, lots found in feet and hands

*melanocytes function

product melanin (pigmentation)

*what cells are in the stratum spinosum

langerhands cells

*langerhans cells function

immune functions

*what cells are in the stratum granulosum

lamellar granules (keratohyalin)

*what makes up the stratum corneum

dead cells filled w keratin

*what is the 5th layer of the epidermis only seen in thick skin in the hands and feet

stratum lucidum

*what is the thickness of the dermis

0.3mm-3.00mm

which skin layer is thicker

dermis

*what are the layer of the dermis

papillary layer and reticular layer

*what is found in the papillary layer of the dermis

loose, areolar connective tissue

*what is found in the reticular layer of the dermis

dense irregular connective tissue.

*what is found in both layers of the dermis

blood vessels, sebaceous glands, hair follicles, connective tissue

*primary lesions cause

directly from a disorder

*primary lesion vs secondary lesion example

primary- misquito bite

secondary- scratching at a misquito bite and damaging the skin around it

secondary lesions cause

skin changes due to primary lesion (indirect cause)

typically from scratching/chronic inflammation

*macule and patch characteristics

FLAT, non-palpable

*size of macules

less than 1cm

*size of patches

over 1cm

*examples of macules and patches/possible causes

vitiligo, mongolian spots, freckles, birthmarks, some drug rxns

*papule and plaque characteristics

ELEVATED, solid lesions

*size of papules

less than 1cm

*size of plaques

over 1cm

*examples of papules and plaques

warts, moles, insect bites, psoriasis

*nodule characteristics

elevated, solid, less than 2cm diameter

*what is a nodule over 2cm called

a tumor

*wheal characteristics

a edematous plaque or papule from infiltration of the dermis w fluid

firm, red, fluid filled, may only last a few hrs

*common cause of wheal

allergic rxns, urticaria

*characteristics of vesicles and bullae

circumscribed collection of free fluid

*size of vesicles

less than 0.5cm

*size of bullae

over 0.5cm

*common cause of vesicles and bullae

burns

*characteristics of pustules

circumscribed collection of leukocytes and free fluid that vary in size

*cyst characteristic

sac like structures/pockets full of oil, fluid and other substances

*abscess characteristics

infected cyst, usually w pus (red, warm to touch)

*examples of primary lesions

macules, patches, papules, plaques, nodules, wheal, cysts, abscesses, tumor, vesicle, bulla, pustule

fissure characteristics

linear, sharply demarcated, deep crack into dermis

what pts often have fissuers

psoriasis, eczema pts

erosion chracteristics

loss of superficial epidermis, heal w/o scarring (shoe blisters that pop)

ulcer characteristics

epidermis and dermis damage, scars when it heals

characteristics of skin atrophy

depression and/or surface change, thinning of epidermis and dermis, often caused by lots of steroid cream use or steroid injections

what makes up crust on the skin (scabs)

dried serum and cellular debris

characteristics of scars

abnormal formations of connective tissue. initially thick/pink but can become white and atrophic

characteristics of scale

made up of dead EPIDERMAL cells produced by abnormal keratinization and shedding

see lots of loose flakes, often seen in eczema and psoriasis pts

excoriation characteristics

superficial erosion, scratching, often linear or punctuate

characteristics of lichenification

thickening of epidermis, with accentuation of skin markings (can still see the skin folds)

characteristics of eschar

black and hard crust, tissue necrosis of epidermis and/or dermis (may be from pressure ulcers)

examples of secondary lesions

scales, crust, fissues, ulcer, scar, atrophy

*what is the fitzpatrick scale

the scale measuring skin tone from 1-6 w 1 being the lightest (always burns never tans) to 6 being the darkest (never burns always tans)

*what problems are we thinking if a pt has erythema (redness of skin)

inflammation, infection

*what is blanching

when you press on a red spot and it turns white and then goes back to red

*what causes purpuric (dark purple) skin

extravasation from cutaneous vessels, often seen in systemic illnesses and can be serious

*purpuric characteristics

non-blanching, petechiae (small/pinpoint)

*uniform shape throughout the lesion in circle

discoid/round

*uniform shape throughout the lesion in oval

oval

*ring shaped with variation in appearance between center and periphery with “central clearing”

annular

*arc or bow or “C” shaped, may be a portion of an annular lesion

arcuate

*target like shape with at least 3 distinct zones: a central disk, peripheral pale ring, and erythematous halo

targetoid

*central indentation shape, like a belly button

umbillicated

*distribution separated from one another

discrete distribution

*distribution clustered next to each other

grouped distribution

*small lesions combined to create a larger affected area

confluent distribution

*lesions isolated to area(s) of body

localized distribution

*dispersed everywhere

generalized distribution

*distributed along a dermatome

dermatomal distribution

*thin straight line of lesions

linear distribution

*wave or snake like

serpiginous distribution

*lace or net like

reticular distribution

*uniform distribution on both sides of the body

symmetrical distribution

*located in areas of sunlight exposure

photo distributed

*what should your Hx compose of

Onset, Location, Duration, Character, Aggravating, Relieving factors, Timing, Severity

*finding out in Hx when issues started, what pt was doing when it started, sudden or acute

onset

*finding out in Hx where it started on the body and where you physically were when it started

location

*finding out in Hx how long something has lasted

how long it has lasted

*finding out in Hx what the skin issue acts/feels like (burning, itching, hot, none)

character

*finding out in Hx what makes the problem worse

aggravating

*finding out in Hx any treatments the pt has already tried

relieving factors

*finding out in Hx when the issue is worse (when outside, working out, at night, etc)

timing

*finding out in Hx whether the issue is improving or getting worse and how bad it is now

severity

additional things to ask about when taking Hx

associated symptoms, family hx, medical and surgical hx, job, hobbies, allergies, meds

what can be seen on a physical examination

location, lesions, distribution

possibly diagnostic tools for derm

biopsies, patch test (allergies), scraping (KOH prep and gram stain), I&D w culture, Tzank smear and PCR, woods light, labs (infections), imaging (tumors)

treatment options for derm

cryotherapy (liquid nitrogen), laser therapy, excisions, meds (topical and oral)