Skin stuff

Question 1

Leser-Trelat sign

Answer 1

sudden appearance of multiple seborrheic keratoses, indicating an underlying malignancy

Question 2

Why is the crepitus in necrotizing fascitits?

Answer 2

methane and CO2 production

Question 3

What is scalded skin syndrome?

Answer 3

exotoxin of staph destroys keratinocyte attachements to the stratum granulosum (no the epidernam-dermal juction- if that is destroyed, you have toxic epidermal necrolysis). see fever and generalized erythematous rash.

Question 4

What is hairy leukoplakia?

Answer 4

white painless paques on the tongue that can’t be scraped off. see in HIV positive pts. EBV mediated

Question 5

Pemphigus vulgaris vs. bullous pemphigoid: severity, immunofluorescence, Nikolsky sign

Answer 5

vulgaris is more severe. immunofluoresence in vulgaris is against the desmosomes and you see abs in a reticular pattern. nikolsky sign positive (separation of epidermis upon manual stroking of skin).
in pemphigoid, you have Ig Ab against hemidesmosomes: linear pattern at dermal-epidermal junction.
nikolsky sign negative

Question 6

dematitis herptiformis

Answer 6

pruritic papules, vesicles, and bullae (often on elbows). depositions of IgA at the tips of dermal papillae. associated with celiac disease

Question 7

What is toxic epidermal necrolysis?

Answer 7

severe form of stevens-johnson. destruction of the dermal epidermal junction in > 30% of body

Question 8

What malignancies are associated with acanthosis nigricans?

Answer 8

visceral malignancy like gastric adenocarcinoma

Question 9

Actinic keratosis

Answer 9

premalignant lesions caused by sun exposure. small, rough, erythematous or brown