DERMATOLOGY Flashcards
RMSF
fever, chills, N/v, photophobia, myalgia, arthralgias THEN 2-5 days later you develop a
petechial rash on forearms, ankles, wrists, that spreads towards trunk and becomes generalized.
DX: PCR essay with rickettsii Antigen
TREATMENT- doxycycline for everyone.
Erythema Migraines
Target bullseye, usually appears in 7-14 days POST being bitten
by a deer tick. Rash is hot to touch with rough texture, flu like symptoms. DX: B. Burgdorferi via
ELISA, then confirm with western blot. Increased ESR. TREATMENT: Less than 7 Amoxicillin or
cefuroxime. Older than 7 - Doxycycline
Melanoma
Dark Moles, uneven texture, different colors, irregular, > 6mm, could be itchy
Stevens Johnson Syndrome
Abruptly, hives, blisters, petechiae, purpura,
necrosis, sloughing of tissues. Extensive mucosal involvement. Prodrome of fevers with flu like
symptoms. Triggers: Allopurinol, anticonvulsants, PCN, sulfonamides, NSAIDS. HIV ppl have
higher risk for this syndrome.
Psoriasis
Inherited. Pruritic erythematous plaques, fine silvery-white scales with pitted fingernails.
Scalp, elbows, knees, sacrum, intergluteal folds.
o (Koebner phenomenon- new psoriatic plaques form over skin trauma)
o (Auspitz sign- pinpoint bleeding when plaques are removed).
o TREATMENT: Topical steroids, Tar preps (mild). For (severe) do anti-TNF, or immunologic
Acanthosis Nigricans
velvet hyperpigmented patches most common on back of neck or skin folds-
DM resistance
Scabies
itching at bedtime. Permethrin cream treat everyone wash sheets and everything else in hot water
Atopic Dermatitis (eczema)
Inherited. Extremely itchy. On flexural folds, neck, hands. Inc. IgE.
“small vesicles that rupture leaving painful, bright-red, weepy lesions” they become lichenified from
itching.
First line: Topical steroids. Avoid hot water/soaps. PO antihistamines
Tinea Corporis
“ring like itchy rash, slowly enlarge central clearing”-Treatment: most respond to
topical antifungals, if severe do oral Lamisil
Actinic Keratosis
Precursor to squamous cell carcinoma. “numerous dry round and pink to red
lesions” with a rough and scaly texture. Does not heal. Slow growing in sun exposed areas.
Diagnosis: BIOPSY Golden Standard. Treatment: Sm. (cryotherapy), Lrg. (5-FU cream)- which
causes ur skin to ooze, crust, scab, redness.
Seborrheic Keratosis
soft round wart light tan to black “pasted on”. Asymptomatic and benign
Cellulitis
Deep dermis poor demarcated lower legs. DVT
RISK, DM WITH CELLULITIS WATCH FOR OSTEOMYELITIS
Erysipelas
Group A strep, Upper dermis, clear demarcated, cheeks, shins.
TREATMENT- Dicloxacillin QID x 10d. Cephalexin, Clinda. PCN ALLERGY? Do Azithro x 5d.
o MRSA TREATMENT: Bactrim, doxy, mino, clinda. If sulfa allergy do not use Bactrim
Basal Cell Carcinoma
pearly, waxy, skin lesions, atrophic, ulcerated center that does not heal
Molloscum Contagiosum
white plug, dome shaped. Highly contagious
Varicella Zoster Virus
“contagious 48 h. before, until all lesions crusted over” low grade fever,
generalized lymphadenopathy, intense itching, erythematous macules, papules develop over macules,
then vesicles erupt. “initially on trunk, then scalp and face” TREATMENT supportive,
antihistamines, acyclovir 20mg/kg 5xd. If given first 24 hours works best
Acne Vulgaris (common acne)
mild (topicals only): *open/closed comedones w/ or w/o sm. papules. Retin-A, acne worsens 4-6
weeks if no improvement in 8-12 weeks increase dose or add erythromycin, benzoyl peroxide.
o Moderate (topicals plus antibiotics): papules, pustules w/ comedones. Continue with topicals
combined with topical antibiotics. Then add ORAL antibiotics tetra, mino, doxy.
o Severe: with painful indurated nodule, cysts, abscesses, pustules. Accutane- check LFTs, 2 forms
of contraceptives, monthly prego testing, only prescribe 1-month supply.
Acne Rosacea
chronic small acne like papules/pustules around nose mouth chin. TREATMENTMetrogel,
Azelex. Low dose tetracycline
Impetigo
Gram positive. Itchy, pink-red lesions evolve into vesiculopustules that rupture; honeycrusted
lesions. If bullous: large blisters. Severe: Keflex, dicloxacillin. PCN Allergic: Azithro, clinda.
If NO BULLAE- Bactroban
Scarlet fever (AKA Scarlatina)
“sandpaper textured-pink rash with sore throat” strawberry tongue,
rash starts on head and neck, spreads to trunk. The skin THEN desquamates
LICHEN PLANUS
SMALL FLAT TOPPED, RED TO PURPLE BUMPS THAT MAY HAVE
WHITE SCALES/FLAKES. WHISPY GREY WHITE STREAKS CALLED WICHHAMS STRIAE.
INNER WRISTS FOREARMS, AND ANKLES. IF ON SCALP CAUSE HAIR LOSS. Causes hep
C, medications, contact with chemicals.
Spider bite
fever chills, n/v, located arms, upper legs, or the trunk. Bitten area becomes swollen, red,
and tender, and blisters appear within 24-48 hours. Necrotic in center, which kills the tissue. Ice packs
to wound and cold inactivates the toxin, tx like cellulitis of the skin, abx ointment at first, watch etc.
Pityriasis rosea
itchy, herald patch, x-mas tree pattern, rash hands soles/feet think to test for
secondary syphilis RPR then VDRL are screening, then dx FTA-ABS