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Flashcards in MTB - Dermatology Deck (79):
1

ab's to intercellular space of epidermal cells

pemphigus vulgaris

2

causes of pemphigus vulgaris:

idiopathic
ACE inhibitors
Penicillamine

3

3 diseases that have positive Nikolsky's sign

pemphigus vulgaris
TEN
SSSS

4

are the lesions in pemphigus painful or pruritic?

painful

5

most accurate dx test - pemphigus vulgaris

biopsy of the skin

6

DOC: pemphigus vulgaris

glucocorticoids - prednisone

7

what drugs can be used in pemphigus if steroids are ineffective?

azathioprine
mycophenolate
cyclophosphamide

8

dz characterized by tense bullae formation, usually in an elderly person

bullous pemphigoid

9

Dx. test - bullous pemphigoid

biopsy w/ immunofluorescent abs

10

Tx. bullous pemphigoid

systemic steroids (prednisone)
alternatives:
- tetracycline
-erythromycin w/ nicotinamide

11

Pemphigus Foliaceus

blistering dz assoc with other autoimmune diseases or drugs (ACE inhibitors or NSAIDs); much more superficial than pemphigus

12

a patient presents with nonhealing blisters on sun-exposed parts of the body, hyperpigmentation of the skin and hypertrichosis of the face - dx?

porphyria cutanea tarda
- abnormal photosensitivity reaction

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porphyria cutanea tarda is associated with...

alcoholism
liver disease
hep C
OCP use
liver dz - chronic hepatitis, hemochromatosis
diabetes

14

Dx test - porphyria cutanea tarda

urinary uroporphyrins

15

Tx. porphyria cutanea tarda

- stop drinking alcohol
- stop estrogen use
- use barrier sun protection
- use phlebotomy or deferoxamine
- chloroquine (increases excretion of porphyrins)

16

uriticaria

hypersensitivity reaction mediated by IgE and mast cell activation resulting in wheals and hives and pruritus.

17

Medications causing uriticaria

aspirin
NSAIDs
morphine/codeine
penicillins
phenytoin
quinolones

18

MCC of uriticaria

medications
insect bites
foods
emotions
contact w/ latex

19

Management - uriticaria

severe and acute? first generation anti-histamines
chronic? newer gen, nonsedating anti-histamines

20

morbilliform rash

typical type of drug reaction - generalized maculopapular eruption that blanches with pressure; mediated by lymphocytes

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tx. morbilliform rash

antihistamines

22

causes of erythema multiforme

penicillins
phenytoin
NSAIDs
sulfa drugs
infection w/ herpes simplex or mycoplasma

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describe erythema multiforme

targetlike lesions esp. on palms and soles; does not involve mucosal membranes

24

Tx. erythema multiforme

antihistamines

25

Stevens-Johnson syndrome

Hypersensitivity reaction involving < 10-15% of BSA and mucous membrane involvement (oral cavity and conjunctivae)

26

What meds can cause SJS?

penicillins
sulfa drugs
NSAIDs
phenytoin
phenobarbital

27

Management of SJS

pts should be managed in burn unit (high risk for infection, dehydration and malnutrition)
meds to try: IVIG, cyclophosphamide, cyclosporine, thalidomide

28

Toxic Epidermal Necrolysis

most serious version of cutaneous hypersensitivity
- involves from 30-100% of BSA w/ mortality of 40-50% (MCC of death is due to sepsis)

29

Dx. TEN

skin biopsy

30

fixed drug reaction

localized allergic drug reaction that recurs at precisely the same anatomic site on skin w/ repeated drug exposure leaving a hyperpigmented, sharply demarcated spot

31

tx. fixed drug reaction

topical steroids

32

causes of erythema nodosum

pregnancy
recent streptococcal infection
coccidioidomycosis
histoplasmosis
sarcoidosis
IBD
syphillis
hepatitis
enteric infections - Yersinia

33

tx. erythema nodosum

analgesics, NSAIDs

34

best initial test for fungal infection of the skin

KOH prep

35

most accurate test for fungal skin infection

culture of fungus (take up to 6 weeks)

36

Tx. onychomycosis or tinea capitis

oral terbinafine or itraconazole
6 weeks - fingernails
12 weeks - toenails

37

s/e: terbenafine

hepatotoxic --> monitor LFTs periodically

38

s/e: systemic ketoconazole

hepatotoxicity
gynecomastia

39

which anti-fungal does NOT come in a topical form

fluconazole

40

Tx. mild bacterial skin infections

dicloxacillin, cephalexin (Keflex) or Cefadroxil (Duricef)

41

Tx. moderate-severe bacterial skin infections

IV oxacillin/nafcillin or IV cefazolin

42

pt with bacterial skin infection, gets a rash with penicillin - what drug can you use?

cephalosporins are OK (Cefadroxil or cefazolin)

43

pt with bacterial skin infection, anaphylaxis allergy to penicillin - what can you use to treat his infection?

macrolides - erythromycin, azithromycin, clarithromycin
newer FQs

44

MC organisms causing necrotizing fasciitis

Streptococcus
Clostridia

45

CF: necrotizing fasciitis

very high fever
portal of entry to skin
pain out of proportion to superficial appearance
bullae
palpable crepitus

46

Dx. necrotizing fasciitis

elevated CPK
Imaging showing air in the tissue/necrosis
best initial step: SURGERY (debridement)

47

Tx. necrotizing fasciitis

Ampicillin/Sulbactam
Ticarcillin/Clavulanate
Piperacillin/Tazobactam
if strep infection: Clindamycin + Penicillin

48

what has the best efficacy for decreasing the risk of postherpetic neuralgia from herpes zoster

rapid admin of acyclovir

49

most effective analgesic for postherpetic neuralagia

gabapentin

50

Criteria for Toxic Shock Syndrome

fever > 102
systolic BP < 90
desquamative rash
vomiting
involvement of mucous mbs of eye, mouth and genitals

51

Lab findings in TSS

elevated Cr, CPK, LFTs
lowers platelets

52

Tx. TSS

1. IVF
2. pressors ie DA
3. antistaph meds: oxacillin, nafcillin or cefazolin (if MRSA - vancomycin, linezolid)

53

Staphylococcal Scalded Skin Syndrome

Skin infection mediated by toxin released by staphylococcus causing sloughing off of superficial layers of epidermis (granular layer) in sheets (positive Nikolsky); no other organ involvement like as in TEN

54

Tx. SSSS

manage in a burn unit
Oxacillin/Nafcillin

55

Tx. Anthrax

Ciprofloxacin
Doxycycline

56

Tx. seborrheic dermatitis

liquid nitrogen or curretage
- removal only for cosmetic purposes

57

Tx. actinic keratosis

cryotherapy, topical 5FU, imiquimod, topical retinoic acid, curettage

58

chemotherapy for Kaposi's sarcoma

liposomal Adriamycin and vinblastine

59

Tx. psoriasis

1. emollients
2. salicylic acid - removes crust
3. topical steroids (if localized)
4. topical vitamin D (calcipotriene) and vitamin A (tazarotene) (chronic psoriasis)

60

if psoriasis covers > 30% of BSA, treatment?

PUVA therapy

61

severe, widespread and progressive psoriasis - tx?

methotrexate

62

seborrheic dermatitis

oversecretion of sebaceous material; HS rxn to a superficial fungal organism (pityrosporum ovale)

63

Tx. seborrheic dermatitis

low potency topical steroids - hydrocortisone
topical antifungals
zinc pyrithione shampoo

64

stasis dermatitis

hyperpigmentation that is built up hemosiderin in tissue from long periods of venous incompetence of LE (no way to reverse this)

65

Tx. keloid scars

intralesional corticosteroids
- recurrence after treatment is common

66

Tx. psoriasis localized to the skin

topical high potency steroids (betamethasone 0.05%)

67

Tx. psoriasis that involves > 30% of the body surface area

phototherapy with UVB radiation

68

when is MTX used in psoriasis?

severe psoriasis
psoriatic arthritis
psoriasis involving the nails

69

drugs that may exacerbate psoriasis lesions

1. beta blockers
2. antimalarial drugs
3. NSAIDs
4. ACE inhibitors
5. lithium

70

stage 1 pressure ulcers

nonblanchable erythema of intact skin

71

stage 2 pressure ulcers

superficial ulcers causing a partial thickness of epidermis, dermis or both

72

stage 3 pressure ulcers

full thickness loss with damage to subcutaneous tissue that may extend to but not through any underlying fascia

73

stage 4 pressure ulcers

very deep ulcers causing full thickness loss with extensive destruction that may damage adjacent muscle, bone or supporting structures

74

tx. stage 3 or 4 pressure ulcers

pack with saline moistened gauze or cover with occlusive dressing

75

most accurate test for dx of psoriasis

skin biopsy
- epidermal hyperplasia or hyperproliferation with neutrophillic infiltrate into stratum corneum and thinned to absent granular layer of epidermis

76

initial drug of choice for psoriatic arthritis

Methotrexate
- once weekly low dose regimen

77

topical treatments for psoriasis

low potency steroids (hydrocort) - face, intertriginous areas, thin plaques
high potency steroids (thick plaques)
anthralin - mild psoriasis
calcipotriene - moderate plaque psoriasis

78

clinical associations with alopecia areata

1. exclamation point hairs, esp at periphery
2. nail pitting
3. other autoimmune conditions: thyroid dz, vitiligo, pernicious anemia

79

drugs implicated in telogen efflivum

beta blockers
anticoagulants
systemic retinoids
anticonvulsants
antithyroid medications