Online med ed --Dermatology

Question 1

Pemphigous vulgaris vs pemphigoid

Answer 1

vulgaris: the bad one, involving antibodies to desmosomes that connect epithelial cells together, PE shows positive nikolsky sign (easily broken down skin with traction), and lesions in oral mucosa, treat with steroids
pemphigoid: occurs in older people, antibodies against hemidesmosomes so no connection to basement membrane, no Nikolsky sign and no involvement of oral mucosa, treat with steroids

Question 2

Dermatitis herpatiformis

Answer 2

blister-like lesions on extensor surfaces and buttocks caused by deposition of IgA

seen in Celiac disease

Dapsone will make blisters go away for symptomatic relief, but avoiding celiac is long-term mainstay tx

Question 3

Wood lamp on urine positive for coral red

Answer 3

porphyria cutanea tarda

Presents with blisters in sun-exposed areas

brought out with insult like HVC, hemochromatosis, or initiation of OCP

Question 4

Biopsy and staining for pemphigus vulagris vs pemphigoid

Answer 4

vulgaris: immunoflurescence everywhere
pemphigoid: IF at basement membrane

Question 5

redness and flaking of eyebrows and scalp

Answer 5

seborrheic dermatitis

tx with selenium shampoo to kill anti-fungals

Question 6

silver scale on erythematous patch that bleeds when picked and often on extensor surfaces

Answer 6

psoariasis

1st line: UV light
2nd line: topical steroids

NOTE: if person has some risk factors for lymphoma, biopsy lesion. if joint sxs, consider seronegative arthropathis

Question 7

Herald patch =

Answer 7

pityrasis rosea

can be syphillis if on hands and soles –> send RPR

Question 8

medication induced purple papule

Answer 8

lichen planus

treat with topical steroids

Question 9

atopic dermatitis =

Answer 9

eczema

asthma, allergies, atopy triad

Question 10

Management of eczema

Answer 10

(1) avoid trigger
(2) emulsions for symptomatic relief
(3) topical steroids

Question 11

causes of erythema multiforma

Answer 11

lyme
syphillis
chronic HSV
early SJS/TEN

Question 12

Drugs that commonly produce skin rxns

Answer 12

anti-convulsants
sulfa drugs
penicillin
cephalosporin
anti-retroviral

Question 13

Bowens disease =

Answer 13

SCC in situ

Question 14

Vitiligo w/u

Answer 14

woods lamp showing hypopigmentation

biopsy showing absence of melanocytes

Question 15

Ash leaf spot

Answer 15

tuberous sclerosis

look for shagreen patches and adenoma sebaceum

MR and seizures

confirm with woods lamp
and identify tumors on CT

Question 16

Tinea capitis: TX

Answer 16

ORAL griseofulvin

Question 17

Diagnosis of tinea capitis

Answer 17

KOH prep

Question 18

Dark red well-defined, indurated lesions climbing up limb

Answer 18

involving lymphatics

erisypelas

tx with amoxicillin

Question 19

Treatment of acne

Answer 19

comedones only –> retinoids
Inflamed comedones + pustules –> benzyl peroxide
Refractory–> doxycycline, then isotretinoin

Question 20

Onychomycosis: TX

Answer 20

ORAL terbinafine

NOTE: as is prolonged tx and can be hepatotoxic, confirm first with KOH prep

Question 21

sulfa drugs (3)

Answer 21

thiazides, furosemide, sulfonylureas

Question 22

Type IV hypersentivity rxn mediated by ____

Answer 22

T cells (not auto-antibodies, which is type II)

Question 23

Painful vesicles with hemorrhagic crusting as well as LDN in an infant with eczema

Answer 23

eczema herpeticum

a complication of eczema causes by a superimposed HSV infection usually type 1

Question 24

Suppurative vs subacute thyroiditis

Answer 24

suppurative: tender, local infection of thyroid, euthyroid
subacute: postviral, tender, hyperthyroid

Question 25

5 culprit organisms in reactive arthritis

Answer 25

yersinia, shigella, salmonella, campylobacter, chlamydia

Question 26

Causative pathogen behind osteomyelitis after a puncture wound through the sneaker

Answer 26

pseudomonas

Question 27

Cysts in the muscle or brain

Answer 27

cystercicosis Taenia solium

Question 28

Cystic liver lesion with eggshell calcification =

Answer 28

hytadid cyst (Ehinococcus granulosos) dogs are definitive host

Question 29

Fxs, back pain, anemia, and hypercalcemia in an elderly patient

Answer 29

multiple myeloma

Question 30

Painful sensorimotor polyneuropathy, skin lesions (hypo- and hyperpigmented, hyperkeratotic), pancytopenia, and mild transaminase elevation =

Answer 30

arsenic toxicity

Question 31

Tinea Capitis: clinical features

Answer 31

scaly erythematous patch on scalp hair loss with residualblack dot possible LDN human-to-human or fomite (shared combs) transmission

Question 32

Atopic dermatitis: infants vs adults

Answer 32

eczema infant: itchy, scaly, crusted lesions on extensor surfaces, trunnk, cheeks, and scalp child/adult: lichenified plaques in flexural creases

Question 33

salmon-colored, hyper- or hypopigmented macules sometimes covered by fine scales, most commonly on upper trunk and extremities

Answer 33

Tinea versicolor (superficial nondermatophyte fungal skin infection caused by Malassezia species)

Question 34

Intense pruritus that is worse at night, pustules, finger web involvement, and excoriation =

Answer 34

scabies

Question 35

Scabies: TX

Answer 35

topical permethrin or oral ivermectin

Question 36

Acute urticaria: clinical presentation

Answer 36

well-circumscribed raised erythematous plaques Lesion oval, round, or serpinginous intense pruritis lesions can worsen over minutes to hours, then resolves w/in 24hrs

Question 37

Tx of acute porphyria cutanea tarda

Answer 37

phlebotomy hydroxychloroquine HCV tx

Question 38

erythema nodosum: disease associatiocns

Answer 38

tender red nodules over shin sarcoid coccidiodomycosis UC TB

Question 39

Nontender, firm, hyperpigmented nodules that dimple in the the center when squeezed and are usually <1cm in diameter

Answer 39

dermatofibroma | d/t fibroblast proliferation and most commonly occur on the lower extremities