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Flashcards in Dermatology Deck (104):
1

flat spot less than 1cm (non-palpable, just visible)
ex:freckles, tattoos

macule

2

flat spot>1cm
ex:port wine stain

patch

3

solid, elevated lesion

papule

4

same as papule but >!cm and flat-topped
ex: psoriasis

plaque

5

palpable, solid lesion >1cm, not flat-topped
ex: small lipoma
erythema nodosum

nodule

6

elevated circumscribed lesion

vesicle

7

same as vesicle but >5mm (large blister)
ex. contact dermatitis, pemphigus

bulla

8

Itchy, transiently edematous area
ex:allergic reaction

wheal

9

erysipelas

upper dermis
superficial lymphatics

may appear raised with clear line of demarcation

10

cellulitis

deeper dermis
subcutaneous fat

11

risk factors for erysipelas and cellulitis

chronic skin problems
diabetes mellitus
chronic swelling of LE
IV drug use
immunocompromiased state
penetration of skin (surgery/trauma)
previous cellulitis

12

Diagnosis and labs in cellulitis and erysipelas

Clinical diagnosis
increased WBC count, ESR, CRP
blood cx

13

Common organisms in cellulitis

1. beta- hemolytic strep
s. pyogenes, group B strep

2. s. aureus common in abscesses

14

How do we treat cellulitis

non-purulent cellulitis:
PO- dicloxacillin
cephalexin
clindamycin

IV- cefazolin
nafcillin
clindamycin

purulent cellulitis:
PO- clindamycin
TMP-SMX
Doxycycline
Linezolid

IV abx-
vancomycin

15

Skin abscesses

collection of pus within dermis and deeper skin tissues

16

Furuncle (boil):

infection of hair follicle
purulent material extends through dermis into subQ tissue

often drains spontaneously

17

Carbuncle

coalescence of several inflamed follicles

18

Diagnosis of abcess, furuncle, carbuncle

clinical

culture is indicated for bacterial idenfication
-s.aureus in 75% of cases

19

Treatment of skin abscess

let the pus out

if large,
incision and drainage
for patients at risk of endocarditis: vancomycin 1hr prior to incision and drainage

oral: clindamycin, tmp-smx, doxycycline, linezolid

IV: vancomycin

antibiotics are often unsuccessful because you need to get the pus out

20

Hidradenitis suppurative

recurrent infection/occlusion of apocrine glands

MC site: axilla

Tx:
-general measures: avoid skin trauma, gentle cleansing, smoking cessation, weight loss

-mild disease: topical clindamycin daily, punch debridement

second line: clindamycin with rifampin

severe disease: oral doxycycline or minocycline, more invasive surgical debridement
-alternative treatments: intralesional steroids, anti-adrenergic drugs, TNFa inhibitors, oral retinoids

21

necrotizing fasciitis

infection spreading along fascial plane

polymicrobial- anaerobes, gram +, gram -
GAS
often in the setting of some systemic disease

H and P:
unexplained, excrutiating pain in the absence of or beyond areas of cellulitis

bulla, necrosis, crepitus

Dx: surgical exploration is the only way to definitively diagnose, as well as to treat

rapidly worsening cellulitis with severe pain

Xray: crepitus, subcutaneous air can be seen with plain film on an xray

22

Fournier gangrene

perineal cellulitis with abrupt onset and rapid spread

this is a urological emergency

23

What is the general treatment for necrotizing fasciitis?

immediate aggressive surgical debridement

abx:
1. carbapenem (imipenem or meropenem)
or beta-lactam plus beta-lactamase inhibitor (piperacillin +tazobactam)
PLUS
2. clindamycin
PLUS
3. vancomycin

24

Gangrene

significant amounts of body tissue necrosis

a chronic condition compared with necrotizing fasciitis

dry gangrene (chronic, distal, severe ischemia) treat with revascularization or allow auto-amputation

wet gangrene: bacterial infection in moist tissue: debridement, possible amputation

gas gangrene: caused by clostridium perfringens
-debridement
-hyperbaric oxygen
-antibiotics

25

Impetigo

contagios skin infection among young children
s. aureus is MCC (MSSA)
s. pyogenes

vesicles that form and rupture to form thick crust, most commonly on the face

Treatment:
mild- mupirocin

moderate-severe: dicloxacillin, cephalexin

MRSA: clindamycin, TMP-SMX, doxycycline

26

Acne vulgaris

1. hyperkeratosis
-retinoic acid (tretinoin)
-isotretinoin is PO, potent
2. sebum overproduction
-isotretinoin
-tretinoin
-spironolactone (anti-androgen, decreases testosterone and cortisol)
-OCP

3. propionibacterium acnes proliferation
-erythromyicin PO
-tertracycline PO
-doxycycline PO
-minocycline PO
-clindamycin PO
-topical clindamycin
-benzoyl peroxide

4. inflammation
-steroids

affecting areas that have hormonally- sensitive sebaceous glands

27

isotretinoin side effects

hepatotoxicity
teratogenic
drying and cracking of skin and lips
depression
elevated TG

28

Acne drugs that can cause photosensitivity

tetracycline
doxycycline
tretinoin

29

Rosacea

cause is not understood
inflammation, UV damage, vascular damage

middle- aged patient
facial erythema with telangiectasias starting at nose and cheeks
recurrent facial flushing provoked by various stimuli including hot/spicy foods, alcohol, temperature extremes, emotional reactions

no comedones, but otherwise looks a little like acne

ocular blepharitis, conjunctivitis, keratitis

bumpy nose (sebaceous gland hyperplasia)- rhinophyma

Topical treatment:
-metronidazole
-azeleic acid

Systemic treatment:
-tetracycline, doxycycline, minocycline
-isotretinoin for severe refractory cases
-laser therapy for rhinophyma

30

HSV

recurrent viral infection of mucocutaneous surfaces

HSV1- oral disease
viral genetic disease in sensory areas

cold sores every month, every 5 years

small painful vesicles around the mouth, lasting several days

eyes, esophagus

Herpetic whitlow- cutical, painful

Dx:
Tzanck smear on a q-tip
viral culture
serology

Tx: treats symptoms, can't be cured
acyclovir
famciclovir
valacyclovir

contagious even when you don't see lesions

Vertical transmission can cause disseminated disease

Newborns can get herpes temporal lobe encephalitis

31

Varicella

primary disease- chickenpox

secondary- shingles

clinical features:
prodrome of malaise, fever, pharyngitis, HA, myalgia for 24 hours prior to rash onset

pruritic evolving rash with teardrop vesicles, crusting over

face, trunk, extremities, spreads over 2-4 days, crusted over by 6 days

superinfection may occur (s. pyogenes)

adults may develop PNA or encephalitis

32

Treatments for children with chickenpox?

antihistamines for pruritis
cut fingernails closely to avoid excoriations leading to bacterial superinfections
acetaminophen for fever
no need for acyclovir in otherwise healthy children younger than 12

acyclovir if:
->12yo
-hx of chronic cutaneous or cardiopulmonary disorders
-taking intermittent oral or inhaled steroids
-chronic salicylates

prevention:
varicella vaccina now given at 1 year and 4 years old

33

Shingles

reactivation of herpes zoster virus

painful, grouped vesicles in a dermatomal distribution

postherpetic neuralgia possible

transmission through direct contact with active lesion (not as transmissible as chickenpox)

treatment:
antivirals if presenting within 72 hours
-valacyclovir
-famciclovir
-acyclovir: high dosing frequency but low cost

Analgesia with opioids
Corticosteroids (prednisone tapered over 7 days) only if severe symptoms and no contraindications. Usually the high risk of side effects outweighs the only modest benefits.

ppx: shingles vaccine for everyone over 50 year
do not give to pregnant women, or immunocompromised

34

Treat postherpetic neuralgia

months, years, fades over time

gabapentin
pregabalin
TCAs
lidocaine patches
capsaicin cream

35

Acne treatment

benzoyl peroxide
topical retinoid or antibiotic
oral antibiotic
OCPs
spironolactone
isotretinoin

36

Rosacea treatment

topical metronidazole or azeleic acid

laser therapy

systemic treatment:
-tetracycline
-doxycycline
-minocycline
-isotretinoin

37

Warts

benign epithelial growths caused by HPV 1-4 (skin)

Genital warts HPV 6 and 11

Treatment options for cutaneous warts:
-2/3 resolve spontaneously within 2 years
-salicylic acid (first line)
-liquid nitrogen
-5-FU and imiquimod
-curettage, trichloroacetic acid, cantharidin (blister juice from beetles), surgical excision

38

Molluscum contagiosum

seem most commonly in children
adults with HIV, perineal region

39

tinea versicolor

-malassezia furfur
-hypopigmented or light brown or pink macules often found on back and shoulders
-hyphae and spores (spaghetti and meatballs) seen microscopically

will scale when scraped

Treatment:
ketoconazole 2% shampoo
topical antifungal (terbinafine)
selenium sulfide
PO antifungal for extensive disease (ketoconazole, fluconazole, itraconazole)
dandruff shampoo can also be affective

40

Tinea

capitis (scalp)
corporis (body)
cruris (groin)
pedis (foot)
unguium (nails)

caused by microsporum, trichophyton, epidermophyton

pruritic, erythematous, blisters, scaly plaques, central clearing

diagnose with KOH, hyphae present

Treatment:
SKIN- topical (clotrimazole, terbinafine, nystatin)
PO- (terbinafine, itraconazole, fluconazole)

Scalp: PO (griseofulvin, terbinafine, itraconazole, fluconazole)
Nails: PO (terbinafine, itraconazole, fluconazole); topical (cilcopirox, efinaconazole)

check LFT before starting these meds

41

Intertrigo

candida albicans
looks like diaper rash
common in skin creases

irritant dermatitis by contrast, won't have satellite lesions, and won't be as much in the folds
KOH shows pseudohyphae

Treat with topical clotrimazole or terbinafine

42

Scabies

RF: crowded living conditions
poor hygiene

Severe pruritis with burrows and papules located on extremities and between fingers and toes

Skin scrapings will show mites and eggs under microscope

treat with permethrin cream
diphenhydramine and corticosteroids help with itching

wash everything in hot water

infection of close contacts is a common complication

43

lice and crabs

diagnosis by direct visualization

all cause pruritis

Pediculosis capitis:
-treat with permethrin cream or shampoo, rinse after 10 minutes, then comb out lice and nits
-alternatives: topical malathion or ivermectin

Pediculosis corporis: body louse
-treat with permethrin cream and leave on for 8-10 hours


Pediculosis pubis: groin lice
-Treat with permethrin or pyrethrin cream and rinse out after 10 minutes, and then comb
-Alternatives: topical malathion and ivermectin
-sexually transmitted

44

Hypersensitivity reactions in the skin (mainly 1 and 4)

Type 1: mast cell degranulation: IgE, immediate allergy

Type 4: delayed type, cell-mediated immune memory response
Morbilliform rash days after 2nd exposure to allergen

Common causes: plants, nickel, soaps, latex

Stop offending agent
remove contact with allergen
topical steroids
oral antihistamines
oral corticosteroids
IM epinephrine

45

Erythema multiforme

erythema multiforme: deposition of immune complexes into superficial microvasculature and mucous membranes
often a drug reaction (PCN, sulfonamides, NSAIDs, PO contraceptives, anticonvulsant medications)
HSV and mycoplasma pneumoniae are common infectious causes that can lead to erythema multiforme

Appearance: skin lesion, target, pale zone, darker outer ring
can be anywhere

lesions develop over 10+ days:
macule> papule> vesicles/bullae in the center of the papule

common sites:
hands/forearms, sole/feet, elbows and knees, penis and vulva

Severe form (EM major) always involves the mucuous membranes and can become SJS/TEN

46

Treatment for erythema multiforme

stop inciting medication
symptomatic treatment with antipruritics
if severe- systemic glucocorticoids (although no proven effectiveness)

if patient also has history of HSV, then antiviral such as acyclovir or valacyclovir

47

SJS and TEN

SJS is severe EM, always involves mucous membranes
skin sloughs,

48

TEN

>30% of BSA
full-thickness epidermal necrosis

treat in a burn unit
IV fluids

Labs:
decreased H/H
increased ALT, AST

IV hydration
acyclovir

49

Seborrheic dermatitis

chronic relapsing dematitis a/w sebacious glands

possible cause is malassezia furfur

erythematous plaques with greasy- looking, yellowish scales

Treatment:
scalp: medicated shampoo (ketoconazole, selenium sulfide, ciclopirox); alternative is tar- containing shampoo

skin: low-potency topical steroids or topical antifungal cream (ketoconazole)

50

What diseases are a/w increased incidence of seborrheic dermatitis?

Parkinson, HIV, psoriasis, immunocompromised patients (transplant patients)

Exacerbations are common in emotional stress and hospitalizations

Severe intractable seborrheic dermatitis may point to HIV infection

51

Seborrheic keratosis

various presentations, variable size, pasted on
no treatment needed

dark
warty

52

Actinic keratosis

precancerous lesion a/w sun exposure

53

Atopic dermatitis

oozing, crusty
often found in children
asthma allergies

dry vesicles

treatments:
skin hydration: emollients
topical steroids
calcineurin inhibitors: tacrolimus or pimecrolimus
severe or resistant cases: UV light therapy, systemic steroids, immunosuppressants (methotrexate, cyclosporine, azathioprine)
antibiotics for open lesions (cover s.aureus and streptococcus)

54

side effects a/w calcineurin treatment

lymphoma
keep duration short

55

psoriasis

immune- mediated
red plaques on knees and elbows

pustules
silvery scales

clinical diagnosis
skin biopsy: thickened epidermis
absent granular layer
nucleated cells in stratum corneum

are you having joint pain as well? check for arthritis

56

psoriasis treatment

mild to mod disease:
-topical steroids and emollients
-alternatives: tar-nased products, topical retinoids (tazarotene); topical vitamin D (calcipotriene), anthralin, calcineurin inhibitors (tacrolimus, pimecrolimus)

Severe disease:
-phototherapy
-oral retinoids
-immunosuppressants (methotrexate, cyclosporine)
-adalimumab, etanercept and infliximab

57

Pityriasis rosea

benign, self- limited inflammatory disease, in children or young adults with possible viral association, seen on trunk

herald patch: 2-5 cm, precedes christmas tree, pink, confirm lack of hyphae with KOH prep

clinical diagnosis

Treatment:
self- limiting
moderate-potency topical steroid for pruritis
severe disease:
UV therapy
acyclovir
erythromycin

58

Erythema nodosum: cause

SPUD BITS

shins, trunk, etc
delayed immunologic reaction to drugs, infection, IBD

Streptococcal infection
Pregnancy
Unknown (idiopathic)
Drugs
Behcet disease
Inflammatory bowel disease
Tuberculosis
Sarcoidosis

H and P:
malaise
arthralgia
tender erythematous nodules (pretibial)
fever

Labs:
possible +ASO
increased ESR
Bx: fatty infiltration

Treatment:
self- limited
NSAIDs
potassium iodid
corticosteroids

59

Lichen planus

pruritic
purple
polygonal plaque, shiny and flat, commonly on the flexor surface (wrist, etc)

Wickham's striae is a white, lace-like pattern on the surface of the papules/plaques

Mucous membrane involvement: Wickham's striae in the lateral buccal mucosa and possibly erosive lesions that may become infected with Candida

Genital involvement: usually limited to violaceous papules on the glans penis in men, vulva of women

RF:
HIV
Hep C

Treatment:
corticosteroids of medium to high potency (topical or intralesional, oral if topical is unsuccessful)

acitretin (oral retinoid)

60

Decubitus ulcers

stage 1: pressure-related, change in color, skin intact

stage 2: superficial ulcer

stage 3: full thickness with damaged tissue

stage 4: full thickness with damage to muscle, etc

Treatment:
good nutrition and hydration
remove pressure on ulcer
debridement
wound care
antibiotics

61

Stasis dermatitis

RF: chronic venous insufficiency. LE
eczematous, inflammatory papules, increased pigmentation, stippling, old hemorrhages

clinical diagnosis
venous reflux is confirmed using duplex ultrasound

62

Treatment for stasis dermatitis

weightloss
compressive dressings of stocking
leg elevation
topical steroids
vein ablation

63

Medications most commonly associated with erythema multiforme

penicillins
sulfonamides
OCPs
NSAIDs
anticonvulsants

64

EM vs. SJS vs. TEN

EM:
milder disease
no sloughing of skin

SJS:
skin-sloughing limited to 30% of BSA

65

Psoriasis- what does it look like?

red plaques with silvery scales
extensor surfaces
Auspitz sign

66

classic presentation of erythema nodosum

pretibial nodules within subcutaneous fat
-painful and erythematous

67

classic presentation of pityriasis rosea

herald patch, followed by rash in Christmas tree patten

no treatment needed

68

classic presentation of lichen planus

pruritic, purple, polygonal, plaques and papules on flexor surfaces of extremities

69

Pemphigus vulgaris

flaccis, easy to rupture blisters, +Nikolsky

almost always with oral lesions

antibodies in epidermis

anti-desmosome antibody

Tx: high dose systemic steroids, azathioprine or mycophenolate mofetil (steroid-reducing adjuvant)
antibiotics for 2ndary infection

fatal without treatment

70

Bullous pemphigoid

tense bullae
rare oral lesions (10-30%)
antibodies found at dermal- epidermal junction

antihemidesmosomes, with better prognosis than pemphigus

topical steroids (clobetasol)

PO steroids (prednisone) if topical steroids aren't possible

chronic management: mycophenolate mofetil
azathioprine
methotrexate

71

Porphyria cutanea tarda

deficiency in uroporphynogen decarboxylase

porphyrin accumulates

acute porphyria
-nervous system:neuropathy, abd pain, mental disturbances

cutaneous porphyria:
-excess porphyrins near the surface of the skin

risk factors: hepatitis C, alcohol abuse, excess iron

classic presentation: blistering lesions

chronic skin thickening on sun-exposed areas, hyperpigmentation, calcification, facial hypertrichosis

diagnosis:
elevated urinary porphybilinogen

diagnosis: elevated plasma porphyrins

treatment:
phlebotomy
hydroxychloroquine
avoidance of sun, alcohol, estrogens, iron supplements

72

Actinic keratosis

precancerous skin lesion
RF: sun exposure
erythematous papule with rough, yellow-brown scales
biopsy: dysplasia


Treatment: topical 5-FU, imiquimod, cryotherapy

0.1%/year risk of squamous cell carcinoma

73

Squamous cell carcinoma

skin cancer of squamous cells of epithelium

RF:sun exposure, arsenic exposure, fair complexion, radiation- especially UVB

painless, well-demarcated, scaly patch or plaque, erythematous, scaling

Treatment: surgical excision (Mohs), radiation

5-10% metastesize

74

Basal cell carcinoma

mc skin cancer
least likely to metastesize
pearly papule
rolled edges

treatment: surgical excision (Mohs), radiation, cryotherapy

75

Melanoma

malignant melanocyte tumor
RF: sun exposure, fair complexion, family history, numerous nevi

Types:
-superficial spreading is most common, grows laterally before vertically (back on men, legs on women)
-nodular: only grows vertically and becomes invasive rapidly
-acral lentiginous: least common, found on palms, soles, and nail beds
lentigo maligna: slow growth, 10-50 years before vertical growth

Labs: excisional biopsy shows atypical melanocytes and possible invasion into the dermis (>.76 mm is associated with increased risk of metastasis)

Treatment:
0.5 cm margin if in situ
1cm margin if 2mm thick +/- lymph node dissection

chemotherapy and radiation if metastasis

Most commonly mets to brain, lung, GI tract

periodic skin checks if history of sun exposure or family history of melanoma

76

ABCDE of melanoma

Asymmetry
Border irregularity
Color
Diameter >6mm
Evolving

Do not shave; excisional biopsy

77

Most important prognostic indicator in melanoma

depth of lesion

78

BCC appearance

pearly papule
telangiectasias

rolled edges if ulcerated

79

Squamous cell carcinoma appearance

papule or ulcer
scaling or keratinization
irregular or disorderly appearance
either painless or painful

80

split-thickness graft

graft composed of epidermis and part of the dermis

abdomen, thighs, buttocks

extensive, large surface areas

81

full-thickness graft

face and hand defects

82

composite graft

fat, nailbed, etc, site-speficit reconstructions are the indication

83

fasciocutaneous flap

skin+subQ tissue+vascular supply
donor sites: forehead, groin, deltopectoral region, thighs

indicated for large defects

84

muscle flap

may include skin (myocutaneous)

donors: TFL, gluteal muscle, lat
indications- deep tissue injury, radiation injury

85

Melasma

dark skin discolration common in pregnant women and those taking OCPs or hormone replacement therapy

Tx by minimizing sunlight exposure and sunscreen
titanium and zinc oxide

Triple combo cream: tretinoin, hydroquinone, mid-potency topical steroid (flucinolone)

86

What are characteristic features of vitiligo

sharply demarcated patches of complete depigmentation (due to loss of melanocytes)
-borders are hyperpigmented
-more common at acral areas and around body orifices

Skin is of normal texture (excludes morphea and lichen sclerosis)

Associated with thyroid disease in 30% of patients (especially women)
mo

most common age 20-30

87

Autoimmune disorders associated with vitiligo

GRaves
autoimmune thyroiditis
pernicious anemia
type I DM
primary adrenal insufficiency
hypopituitarism
alopecia areata
autoimmune hepatitis

88

Treatment for vitiligo

sunscreen to minimize tanning of normal skin, which would increase the contrast

dyes and make-up to camofluage depigmented area

topical corticosteroids (first line)

Tacrolimus or pimecrolimus (calcineurin inhibitors)

Psoralens (topical or oral) + UV light (PUVA or UVB) for extensive disease

surgical mini-grafting is an option when medical therapy fails

hydroquinone for depigmentation of normal skin to match regions of vitiligo (ast resort)

89

Acanthosis nigricans

velvety hyperpigmentation

most commonly seen on lateral folds of axilla, neck, groin

associated with hyperinsulinemia and visceral maligancies

Treat underlying disorder:
diabetes
weightloss
discontinuation of medication (glucocorticoids, OCPs), or treatment of malignancy

Tretinoin (topical)
Calcipotriene (Vit D topical analog)

90

blue mass that does not regress

cavernous hemangioma (venous malformation)

91

Treatment for infantile hemangioma

uncomplicated infantile hemangiomas will gradually resolve within the frist 2 years of life, therefore observation is usually the best treatment

Complicated infantile hemangiomas: oral propanolol, systemic glucocorticoids, vincristine, interferon alpha

92

Clinical features of alopecia areata

asymptomatic, inflammatory, non-scarring areas of complete hair loss

may be precipitated by stress

regrowth after 1st affack in 30% by 6 months, in 50% by 1 year, in 80% by 5 years

10-30% will not regrow hair
5% progress to total hair loss

obtain syphilis screen
CBC
BMP
ESR
TSH
ANA (to rule out pernicious anemia, chronic active hepatitis, thyroid disease, SLE, Addison)

Rule out trichotillomania (pulling out one's hair): look for broken hair shafts of different lengths, consider shaving a small patch oand observe over a few weeks for growth

Treatment:
intralesional steroid injection
topical corticosteroids
minoxidil topical
topical immunotherapy
anthralin cream (children)
oral steroids

93

What name is given to diffuse stress-related hair loss?
What is the treatment?

Telogen effluvium
self- limited
reassurance, stress relief

94

androgenic alopecia

causes are both hormonal and genetic

dihydrotestosterone causes follicular miniturization leading to replacement of terminal hairs by short, thin hairs

inheritance involves both paternal and maternal factors

Treatment:
Finasteride (5alpha-reductase inhibitor)
Minoxidil (topical)

95

Caused by complete lack of melanocytes

vitiligo

96

Hair loss associated with effects of dihydrotestosterone on hair follicles

androgenic alopecia

97

Most common co-morbidity in vitiligo

TSH

98

purple-red lesion on face that does not regress with age

port wine stain

99

infant with bright red lesion that regresses over months-years

strawberry hemangioma

100

benign, small papule that appears on skin with age

cherry hemangioma

101

bright red papule with radiating blanching vessls

spider angioma

102

blue, compressible mass that does not regress

cavernous hamengioma

103

red-pink nodule on a child that is often confused with melanoma

Spitz nevus

104

anti-centromere abs

CREST scleroderma