layers of epidermis?
"Californians Like String Bikinis"
microscopic appearance of Kaposi Sarcoma?
a) Sheets of plump spindle-shaped cells forming slit-like spaces filled with red cells.
B) sheets are intertwined with vascular channels lined by endothelium
c) foci of hemorrhages and hemosideren deposits
microscopic features of
1. Cellular atypia in lower epidermis
2. Hyperkeratosis (hyperplasia of Stratum Corneum)
2. Parakeratosis (nuclei in upper Stratum Corneum)
3. Acanthosis (hyperplasia of Stratum Spinosum=not below stratum basale)
4. Upper dermis: basophilic degeneration of collagen (solar elastosis) and dense lymphocytic infiltration.
(also: Common to see mitosis)
microscopic appearance of Basal
a) Proliferating basal cells protruding from epidermis or forming large nests extending into the dermis.
B) Cells at periphery arranged radially
c) Cell nests separated by mucinous
connective tissue stroma
microscopic appearance of Nevus
of Spitz? DDx?
a) Composed of spindle-shaped and plump epithelioid nevus cells that frequently show nuclear irregularities. (often has a "sunburst pattern" -pic- 96% sensitive for SN)
B) Often confused with malignant melanoma
microscopic appearance of a
a) hyperplasia of melanocytes
b) hyperpigmented basal layer
c) long, narrow rete ridges
growth phase of nodular
Vertical growth phase. The melanoma grows downward into deeper dermal layers and may metastasize.
MOA of photochemotherapy using PUVA?
used for what?
what if it's recalcitrant?
Oral psoralen + UVA (uva activates the psoralen) -->DNA adduct which inhibits DNA replication.
-Inhibits proliferation and
-promotes differentiation of epithelial cells.
-if recalcitrant: use biologics
MOA of Isotretinoin? (is a kind of ___)
decrease sebaceous gland size and activity (is a retinoid, which increase cell prolif., decrease collagenase levels and decreases PGE2 and inflammation)
used for severe cystic acne
MOA of glucocorticoids?
Includes inhibitory effects on arachidonic acid cascade, depression of production of many cytokines and effects on inflammatory cells.
-autoimmune conditions (SLE, Psoriasis...)
granulation tissue consists of...?
aka "proud flesh"
-inlammatory cells (macrophages and PMNs etc)
-proliferation of capillaries;
=sign of healthy wound healing
the definition of a clean wound?
a wound that does not have more than 100,000 microorganisms per gram of tissue. Strep is the exception, however, any presense of it contraindicates wound closure.
classification of burns?
1st degree: epidermis only = nerve endings intact = painful
2nd: into dermis. see blistering (>superficial = more red and painful. deeper = more white and dry)
3rd: through whole dermis. painless.
4th: into subQ, bone, muscle
most common types of bacteria infecting burns?
pseudomonas, strep, staph, mrsa and VRE
condition requiring surgery in contaminated wound?
most infections from surgery will require re-operation or surgery to open up the wound and debride/clean it. Hematomas or pooling of blood can interfere
with healing and promote infection. necrotic tissue must be debrided. in the cases of abscesses (esp abdominal) they have to be drained and debrided for antibiotics to be
effective otherwise they can't reach the infected tissue
timing for pre-operative antibiotics?
as close to the incision time as possible. then post op 4-6 hours later (max of 2 post op doses)
hospital acquired infections causing fever?
pulmonary infxn, UTI, wound, intra-abdominal infxn, pleural empyema, foreign body associated infxn (e.g. prosthetics),
...basically any infxn
causing fever: pulmonary infxn
-atelectasis, aspiration, pulmonary embolism (PE)
causing fever: UTI
-indwelling foley catheter
-urinalysis, culture and sensitivity
best for Dx-ing intra-abdominal infxn?
common organisms causing infxn on implanted devices?
(recall that Staph. can make biofilms)
common etiology of fungal infxns?
wide spectrum antibiotics
most common organisms causing infxn at these sites:
-soft tissue cellulitis
-synthetic vascular graft
-hip or heart valve prosthesis
-group A strep (Strep. pyogenes)
-Staph, Strep. viridans, Enterococcus (Group D Strep.)
biliary tract infxn: common organism?
E. coli, Klebsiella, Enterococcus (Group D Strep)
peritonitis/intra-abdominal infxns: common organisms?
E. coli, other enterobacteriaceae, Bacteroides fragilis, other obligate aerobes
hospital acquired pneumonia: common organisms?
Pseudomonas, serratia, resistant enterobacteriaceae
catheter associated bacteremia: common organisms?
UTI: common organisms?
Staph, Serratia, enterobacteriaceae
Staphylococcus = common cause of ____
-synthetic vascular graft
-infxns/biofilms of prostheses or implants
enterobacteriaceae = common cause of _____
cath. bacteremia and UTI's
Enterococcus (group D strep.) = common cause of _______
-hip or heart valve prostheses
-biliary tract infxns
Which type of skin cancer is Imiquimod
FDA approved for?
BCC (basal cell carcinoma)
what's the clinical pres. of Favre-Racouchot Dz?
-elderly men (>50)
-in the Periorbital/cheek areas (= high sun exposure areas)
-Nodular Elastosis (skin looses its elasticity)
-Thickened, Furrowed, Yellowish skin
Describe the clinical presentation of Seborrheic Keratosis
("barnacles of old age," benign)
*"pasted on"/ "stuck on" appearance
*tan to dark brown in color
clinical presentation of
a Marjolin ulcer?
*burn victims (can develop into Squam Cell Carcinoma, can be delayed by 20-30 YEARS)
*dark skinned individuals
*common in Extremities, often LE
*appear at the margins of ulcers
most common type of skin
basal cell carcinoma (BCC)
recall drug Tx = Imiquimod
vis: starts off looking like a small whitehead, then turn into (pic)
other pic of BCC
*Pearly papule or nodule (like a small whitehead that won't clear)--->
*Rolled, Raised, Pearly border
Tx's for cutaneous Lupus Erythematous?
common patient population acquiring Cutaneous Lupus Erythematous?
-young white women
-Haitians w/ trauma, UV exposure exacerbates lesions
subacute Cutaneous Lupus Erythematous. if they're negative for ANA...?
can still have it. only ~2/3 are + for ANA
Tx for warts?
complications of systemic steroids?
-AVN (avascular necrosis)
-\/ in hypothal.-pituitary axis
-\/ immune sys. fxn
-concern w/ preg. and lactation (b/c hormonal changes)
what is phototherapy commonly used for?
indications for sclerotherapy?
-tributaries to saphenous vein
what is Moh's surgery and when is it indicated?
-four-square, mapped removal of tissue. examined for cancerous cells and more tissure removed per results
-BCC and SCC with ill-defined borders
different types of Impetigo?
(think honey-colored vesicles or crusting. usually S. aureus or Strep. pyogenes)
-macule: flat (bigger=patch) e.g. tinea versicolor
-papule: circumscribed elevation, <1cm
-nodule: deeper than a papule
-plaque: papule >1cm
-vesicle: small fluid containing blister
fungal infxn: under KOH smear looks like "spaghetti and meatballs"
vs. "ring worm?"
"ring worm" = tinea corporis (anular sclay plaque w/ raised edges)
if a skin lesion is pruritic with vesicles, think_____
test for how?
viral (e.g. Herpes Zoster or VZV chix pox)
if a person under a lot of stress starts losing their hair =? other cause?
what should you do to Tx them?
Telogen Effluvium. malnurishment/eating disorders
self-limiting. give it ~6 mos. it's nonscarring
sharply defined de-pigmented macules=?
sharply circumscribed, compressible, fluid-filled lesion=?
common viral skin infxns in kids?
measles (Rubeola) - paramyxovirus
rubella (German Measles)-togavirus
roseola - HSV-6
-fever, conjunctivitis w/ photophobia, morbilliform rash that starts on face and spreads, koplik spots
-rash on face clears as it spreads to body, postauricular and postoccipital nodes
-high fever for a few days
then maculopapular rash on trunk (and possibly extremities)
sharply circumscribe, yellow-orange/flesh-colored lesion on top of scalp w/o hair growing from it. malignant?
no. it's a Nevus Sebaceous
lice on head
white casts on hair shafts, scratches on back of neck
(on eyelashes or pubic area = Pediculosis Cruris)
itch that persists-->keep scratching --> skin thickening =?
Lichen Simplex Chronicus
if suddenly have lots of Sebhorreic Keratosis...?
= Sign of Leser-Trelat
a sign of internal malignancy
what kind of rash on the face might you get with Dermatomyositis?
what else might you see?
(=autoimmune --> inflmmtn of m. and skin)
Gottron's papules (knuckles), shawl and face rash, ^aldolase, +ANA***
- ^ risk of malignancy
cobblestone pattern on tongue and punctuate keratoses=?
Cowden's syndrome/multiple haratoma syndrome (hereditary)
-increased risk of cancer
5 P's of lichen planus?
sig. of lichen planus?
(unknown cause, often wrists and ankles)
papular (raised, but flat up top, like plateus)
assoc.d w/ Hep. C
skin thickening and slivery over erythematous base, usually knees and elbows=?
what's pathognomic for Psoriasis?
Auspitz sign (pinpoint bleeding when you lift the plaque with a blade)
PUVA (oral Psoralens and UVA), topical steroids, Tazanac
what might seem like a fungal infxn in skin folds?
rash that starts w/ a "herald rash" and often after a viral infxn =?
either: cutaneous Cryptococcal infxn
Molluscum Contagiosum (Pox virus) in adults=STD , sig= AIDS defining illness
what is scleroderma?
(autoimmune, 75% female, a. diffuse or b. CREST) large collagen bundles parallel to epidermis replacing subQ. sweat glands and hair follicles obliterated. vis: puffy, taut skin
diffuse scleroderma vs. CREST syndrome?
skin, renal -->HTN, pulmonary, cardiovascular, GI
1. early visceral involvement, anti-Scl-70 antibody**
2. Calcinosis, Raynaud's phenomenon, Esophageal dysmotility, Sclerodactyly (local thickening and tightening of skin), Telangiectasia.
often fingers and face
#1 cause of furuncle?
(what can it lead to?)
(can lead to a carbuncle. multiple carbuncles coalescing, deeper too)
yeast infxn w/ satellite lesions?
erythematous streaking (from Streptococcal infxn spreading through lymph)
(more superficial than cellulitis)
caused by HPV
common mole. benign
hives/wheals, very pruritic (mast cell degranulation)
freckle. normal # melanocytes, ^melanin
atopic dermatitis=? aka?
how is allergic contact dermatitis different?
(atopic ~= allergic) pruritic eruption "eczema"
associated w/ other atopic Dz (asthma, allergic rhinitis)
allergic contact dermatitis lesions are at the place of contact (e.g. nickel, poison ivy)
1. what do you always want to ask someone who (may) have psoriasis?
2. what are two less common presentations of psoriasis?
3. micro. of psoriasis?
(stress may trigger a flare)
4. which forms of psoriasis are medically urgent?
1. any joint pain? (b/c psoriatic arthritis --> permanent joint damage)
2. nail pitting. psoriatic arthritis
3. acanthosis (^stratum spinosum) and parakeratotic scaling
4. erythrodermic (chills and skin pain)
and gen. pustular, pic. (-can-> Steven's Johnson syndrome=ep. separates from derm.)
vitiligo vs. albinism?
some areas/all areas
\/ melanocytes/ \/melanin (fr. \/tyrosinase activity)
Tx for hypopigmentation?
Methoxsalen (AE: ocular damage) or Trioxsalen
(MOA: both \/ cell prolif. and ^differentiation)
...makes sense why they help w/ Psoriasis too
Tx for hyperpigmentation? (which would be____)
hyperpig. w/ preg.= Melasma
Hydroquinone or Monobenzone
(MOA: \/tyrosinase and therefore \/ melanin)
skin is warm to the touch, pt. has fever and chills. acute and painful. =?
cellulitis. infxn of dermis and subQ, often S. aureus or Strep. pyogenes (vs. erysepelas: this is deeper, prolly more swollen)
bacteria causing Necrotizing Fasciitis?
Strep. pyogenes (or MRSA) and anaerobic bacteria
newborn w/ total body erythema and sloughing epidermis=?
scalded skin syndrome
Staphylococcus (via exotoxin)
thrush vs. hairy leukoplakia?
can scrape off / can't (pic.)
fr. candida albicans / fr. EBV
both: in HIV+ patients
sep. of ep. upon manual stroking
+ for Pemphigus vulgaris.
=autoimmune (anti-desmosome IgG --> acantholysis. IF shows netlike pattern of IgG's in ep.)
- for Bullous Pemphigoid (also autoimmune)
progression of skin infxns from Staph. aureus?
folliculitis -deeper-> furuncles(pic) -cluster-> carbuncles(pic)
large blisters w/ auto IgG's under the epidermis in a line?
Bullous pemphigoid (IgG's against hemidesmosomes) "antibodies are 'bullow' the epidermis" in a line
- Nikolsky's sign
pruritic papules and vesicles w/ IgA at the tips of dermal papillae?
what could Phenytoin (an antiepileptic) lead to?
-hyperinsulinemia (e.g. diabetes or cushing's syndrome)
if you see this on someone's shins =?
-coccidiomycosis and histoplasmosis
-TB and Leprosy (mycobacteria)
should a parent be worried about this on their newborn?
no. Strawberry Hemangioma.
grows rapidly and regresses spontaneously at ~6yoa
difference b/w these two?
angioma vs. angiosarcoma/hemangiosarcoma
face, trunk / face, scalp, malignant
Transient Acantholytic Dermatosis=?
trunk, men sweating a lot, pruritic, red-brown papules, heal w/ ^or\/ pigment
Tx: prevention, top. steroids, ant-Histamines
dermatofibroma vs. dermatofibrosacroma protuberans
benign, women, extremities, brown nodule / malig., trunk, solid nodule
ulcerative red lesion w/ Hx of sun or arsenic exposure?
SCC: squamous cell carcinoma
precursor: Actinic keratosis, chronic ulcers (eg Marjolins ulcer)
what might a dysplastic nevus turn into?
(dark, irreg. borders, can have hair)
depth relates risk of metastasizing