Dermatology Flashcards
primary lesion < 1cm
macule
papule
vesicle
primary lesion > 1cm
patch
plaque
bulla
secondary changes
scale erosion crust ulcer scar
configuration
annular linear grouped nummular reticular targetoid
other descriptive terms
color
border
presence of pain, pruritis, alopecia
distribution & its changes w/ time
what begins as a small red bumps that become cloudy & vesicular or bullous
impetigo
a yellow, “honey” crust indicates what?
impetigo
MCC of impetigo
S. aureus
S. pyogenes
tx for impetigo
topically if not widespread
systemic tx occasionally necessary
small follicle-associated papules & pustules
folliculitis
boil including hair follicle
furuncle
multiseptate abscesses including several hair follicles & involves subcutaneous tissue
carbuncle
may progress to abscess
acute, diffuse, spreading, edematous, suppurative inflammation of the subcutaneous tissues, which may be associated w/ abscess formation
cellulitis
what sometimes starts w/ skin trauma or superficial infxn & has ill-defined borders?
cellulitis
what are the top 3 causes of cellulitis
S. aureus Strep pyogenes (Group A strep)-watch closely for necrotizing fasciitis Haemophilus influenzae type b- in the unimmunized
clinical findings of benign intraepidermal tumors caused by HPV
skin-colored papules
irregular (verrucous) surfaces
tx of benign intraepidermal tumors caused by HPV
salicylic acid duct tape tretinoin cream liquid nitrogen canthradin imiquimod (podophyllin)
what causes molluscum contagiosum
pox virus- induces epidermis to proliferate
what do you see w/ molluscum contagiosum?
umbilicated, skin colored papule
chronic course of proliferation & gradual resolution
coxsackie A virus causes what?
enteroviral infxn
“hand, foot, mouth” & sometimes diaper area
enteroviral infxn
low grade fever
malaise
pharyngitis
“hand, foot, mouth”, sometimes diaper area
oral & pharyngeal ulcers
peeling macules on palms & soles
*oral aversion may lead to dehydration
first disease
rubeola (measles)
second disease
scarlet fever (GAS)
third disease
rubella (German measles)
fourth disease
“Duke’s Disease” (no single dz)
fifth disease
erythema infectiosum (parvovirus B19)
sixth disease
roseola, exanthem subitem (human herpes viruses 6 & 7
significance of parvovirus B19 infection
immunocompromised or susceptible pts w/ hemoglobinopathies can experience severe anemia w/ parvovirus
pregnant females w/ infxn can result in fetal complications including fetal death
parvovirus B19 S&S
aka erythema infectiosum/ fifth dz
often asymptomatic
fever, malaise, sore throat
rash
characteristics of parvovirus B19 rash
red “slapped cheek” rash
lacy reticular pattern on limbs & trunk
rash spreads distally
complications of parvovirus B19
arthritis (in adolescents)
aplastic crisis
aplastic crisis in parvovirus B19
parvovirus B19 replicates in erythroid progenitor cells
not a problem for nml individuals
big problem in individuals w/ rapid red cell turnover
what type of d/o’s have problems w/ rapid red cell turnover
sickle cell dz
hereditary spherocytosis
AIDS
chronic hemolytic anemia
roseola (exanthem subitem)
human herpes virus 6 or 7
3 days of fever, often high
eruption of rash for ~12 hrs after fever ends
varicella zoster S&S
- often painful & preceded by burning/pain
- rain drop on a rose petal (vesicle on red base)
- grouped in dermatomal pattern (scattered & evolving in crops in varicella)
- vesicles evolve to become crusted
varicella zoster is tx’d w/ what?
analgesics
antivirals (acyclovir, valacyclovir)
clinical findings in diaper candidiasis
red w/ irregular borders
satellite lesions
starts in intertriginous areas (contact dermatitis is on exposed surfaces)
tx of diaper candidiasis
remove barrier to evaporation
nystatin
clotrimazole
gentian violet
tinea capitis S&S
thickened skin, mild erythema (if any)
black dot appearance of scalp (broken hair shafts)
+/- cervical lympadenopathy
may progress to boggy, swollen, crusted scalp mass called a kerion
what types of organisms may cause tinea capitis
Trichophyton tonsurans
Microsporum canis
tinea capitis tx
oral griseofulvin for 6 wks
black dot appearance of scalp associated w/ what?
tinea capitis
what do you call a boggy, swollen, crusted scalp mass
kerion
infection on body (not including on inner thigh or foot) that is annular in appearance, red w/ peripheral fine scale & expansive
tinea corporis (ringworm)
infection associated w/ tight garments, obesity & sweating?
tinea cruris (jock itch)
tinea cruris (jock itch) s&s
pruritic scaly pink patch on inner thigh
tinea pedis (athlete’s foot)
between toes & on dorsum of foot
fissures, scale & pruritis
tinea’s are tx’d w/
topical antifungals
what spp causes tinea versicolor?
Malassezia sp.
where is tinea versicolor found on the body?
face, trunk, neck
tinea versicolor s&s
light or dark colored patches, sometimes w/ fine scale
more common in teens & young adults
what do you use to treat tinea versicolor?
topically w/:
miconazole/ clotrimazole
sometimes w/ selenium
what causes scabies?
female mite (Sarcoptes scabiei)
the scabies mite likes to burrow into___________and do what?
stratum corneum
deposits eggs
appearance of scabies
burrows in linear pattern
characteristically in intertriginous areas
intensely pruritic, esp. at night
intertiginous areas
finger webs
waist line
bra line
scabies tx
application of permethrin 5%
tx of household contacts
for pruritis: anti-histamines, topical hydrocortisone
lice appearance
nits (eggs) firmly attached to hair
louse (grey bug)
pruritic
scalp, back of head
lice tx
Lindane gamma benzene hexachloride shampoo
permethrin shampoo
irritant contact dermatitis
diaper- moisture
frequent handwashing
allergic contact dermatitis
T-cell immune response to a specific antigen
e.g. nickel, Rhus (poison ivy/oak/sumac)
clinical findings of allergic contact dermatitis
red base
vesicles/bullae
match areas of exposure
extreme itchiness 1-2 days after exposure
tx of allergic contact dermatitis
remove offending agent
cool soaks
topical steroids
severe cases-oral steroids
seborrheic dermatitis (aka cradle cap) clinical findings
mild erythema
thick, waxy, yellow scale
often to hairline, but sometimes extends past
tx of seborrheic dermatitis
combing thru olive oil
more frequent shampoo
more severe cases- zinc pyrithione shampoo, selenium shampoo/lotion, topical steroids
tx for sunburn
NSAIDs, acetaminophen anti-histamines cool compresses topical aloe low potency steroids
hemangioma
benign vascular tumors
usually grow after birth & involute by school age
different from vascular malformations, which grow along with the child
complications of hemangioma
may ulcerate, bleed profusely & scar lumbosacral- spina bifida periorbital- obstruct vision airway Kasabach-Merritt syndrome PHACES syndrome
PHACES syndrome
P-posterior fossa brain malformations H-hemangiomas A-arterial anomalies C-carciac anomalies, coarct of the aorta E-eye abnormalities S-sternal cleft
appearance of urticaria
soft areas of raised skin (papules & plaques) of varying sizes (also called wheal or welt)
pink & red
anywhere on body; may coalesce in various areas
pruritic
cause of urticaria
interaction of antigen & mast cell (can be substance, viral infxn)
mast cell release of histamine causing vasodilation & increased vascular permeability
tx of urticaria
remove offending agent
antihistamine
tx underlying rxn: epinephrine, corticosteroids, cyproheptadine (periactin)
erythema multiforme minor cause
most minor form of widespread immune- mediated skin necrolysis as rxn to drug/ infxn
e.g. HSV, mycoplasma
appearance of erythema multiforme minor
targetoid red lesions w/ inner pale rings & violet centers
centers sometimes bullous
either one mucosal surface affected or no mucosal involvement
little to no systemic sx’s
tx of erythema multiforme minor
antihistamines may help
acyclovir for pts w/ HSV lesions
SJS (erythema multiforme major) appearance
papules progressing to bullae
involvement of multiple mucosal surfaces- oropharyngeal, conjunctiva, nasal, esophageal, tracheal, urethral, vaginal, rectal
SJS may include systemic dysfunction of what?
hepatitis
nephritis
causative agents of SJS
mycoplasma, HSV
drugs: sulfa Abx, anticonvulsants, etc
tx of SJS
hydration pain control emollients prevention of superinfxn controversial: steroids, IVIG
toxic epidermal necrolysis
massive sheet-like denudation of skin
>30% of body surface area involvement
drug rxns include NSAIDs
tx of toxic epidermal necrolysis
same as SJS hydration pain control emollients prevention of superinfxn controversial: steroids, IVIG
acne vulgaris
may begine at age 8
comedones
inflammatory
comedones
closed
open- blackhead
inflammatory acne vulgaris
papular
nodular
pustular
pathogenesis of acne vulgaris
- obstruction of sebaceous follicle
- overproduction of sebum
- overgrowth of nml skin flora (produces irritating free fatty acids)
- redness, swelling, pustule formation
acne vulgaris may also result from
hair oil/pomade or corticosteroids use (topical or systemic)
tx for inflammatory acne
keratinolytic meds
topical Abx
tx for pustular inflammatory acne
consider oral Abx
keratolytic agents
benzoyl peroxide
salicylic acid, azelaic acid
topical tretinoins
Abx for acne vulgaris
topicals (clindamycin, erythromycin)
oral_considered in pustular acne
-tetracycline- also has anti-inflammatory activity
-erythromycin
oral contraceptives for acne vulgaris
may be used for teens who have had regular menses
oral retinoids (isotretinoin, Accutane)
indicated in severe, nodulo-cystic acne
usually prescribed by dermatologist
side effects of oral retinoids
dry lips
elevated transaminases, lipid levels
teratogen
other considerations for acne vulgaris
diet (milk, high glycemic foods) cosmetics & hairspray acne improves during summer worsens w/ stress scrubbing vigorously may worsen long hair jobs w/ high oil/grease exposure
