Dermatology

Question 1

What causes impetigo?

Answer 1

Bullous = Staph aureus Non-bullous = strep pyogenes +/- S. aureus

Question 2

Sx’s of impetigo?

Answer 2

red bumps, turn in to vesicles or bullae that form honey crust when erupt, on face & extremities, often after minor trauma

Question 3

How do you treat impetigo?

Answer 3

Most often–topical abx: clindamycin, mupirocin, Altabax. Oral abx if widespread infxn (Bactrim, clindamycin, cephalexin (not MRSA))

Question 4

What is cellulitis & what causes it?

Answer 4

acute, edematous, suppurative inflammation of subQ tissues w/ or w/o abscess. Caused by S. aureus, S. pyogenes. Often from trauma.

Question 5

What is molluscum contagiosum?

Answer 5

caused by molluscum contagiosum virus (poxviridae): umbilicated skin colored papules usually resolve in 6-9mos

Question 6

What is hand foot and mouth dz?

Answer 6

caused by coxsackie A virus, occurs in summer, macules in mouth (painful)/hands/feet, fever/malaise/sore throat, results in dehydration, tx is supportive

Question 7

What is 5th disease?

Answer 7

Parvovirus B19/erythema infectiosum: slapped cheek rash, reticular trunk rash, fever/malaise/pharyngitis. Also arthralgias, diarrhea, abd pain.

Question 8

What are two complications of 5th disease?

Answer 8

severe anemia/aplastic crisis, fetal death, arthritis

Question 9

What is roseola infantum (exanthem subitem?

Answer 9

herpes 6&7 aka “6th disease”: 9-12mo, high fever x3d, febrile seizure, followed by morbilliform rash

Question 10

What does VZV look like?

Answer 10

pain/burning 1st, then vesicles on a red base grouped in dermatome, become crusted

Question 11

What does diaper candidiasis look like?

Answer 11

in creases–moves outward, beefy red, irregular borders, tx w/nystatin, clotrimazole, gentian violet

Question 12

What is allergic contact dermatitis?

Answer 12

a T cell response to an antigen (nickel, plants), vesicles/bullae on red base, itchy, correspond to exposure areas, tx w/soaks & steroids.

Question 13

What does seborrheic dermatitis (cradle cap) look like?

Answer 13

Thin waxy scales, often to hairline/behind ears, tx w/olive oil, shampooing, dandruff shampoo, steroids

Question 14

What is an infantile hemangioma?

Answer 14

MC tumor of infancy, benign vascular tumor (red), grow rapidly 1st month of life then involute/resolve by age 9 (50% by age 5), do NOT grow along with child

Question 15

What are complications of hemangiomas?

Answer 15

ulceration, bleeding, scarring,

Question 16

What is PHACES syndrome?

Answer 16

abnormalities associated w/lg hemangiomas on face: Posterior fossa brain abnormalities, Hemangioma, Arterial abn, Cardiac abn, Eye abn, Sternal cleft

Question 17

Describe urticaria

Answer 17

Papules and plaques of various sizes, pruritic, pink/red, results from mast cell histamine release

Question 18

Tx of urticaria

Answer 18

antihistamine, corticosteroids, epinephrine

Question 19

What is erythema multiform minor?

Answer 19

minor form of widespread immune mediated skin necrolysis from a drug or infxn. targetoid lesions w/pale rings, violet centers w/up to one mucosal surface affected

Question 20

What is Stevens-Johnson syndrome (erythema multiform major)?

Answer 20

papules progrssing to bullae w/2+ mucosal surfaces involved. May include systemic dysfxn (hepatitis, nephritis), <10% BSA

Question 21

What causes SJS and what is the tx?

Answer 21

causes: drugs, mycoplasma, HSV. Tx: hydration, pain control, emollients, abx.

Question 22

What is toxic epidermal necrolysis (TEN)?

Answer 22

massive denudation of skin, >30% BSA. MC cause is drugs (NSAIDS, ABX, anticonvulsants).