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1
Q

What are the components of the atopic triad?

A

asthma
Eczema
Allergic rhinitis

2
Q

True or false: the diaper area is usually spared in atopic dermatitis in infants

A

True

3
Q

Where does the rash show up on children with atopic dermatitis?

A

Flexural surfaces

4
Q

Long term use of immunomodulator medications increases the risk of what malignancy?

A

Lymphoma

5
Q

What are zonula occludens?

A

Tight junctions in the skin

Presents paracellular movement of solutes

6
Q

What are the adherens junctions?

A

Junction below tight junctions in the skin

Forms belt connecting actin cytoskeletons of adjacent cells with CADherins

7
Q

What are desmosomes?

A

Macula adherens

Structural support via keratin interactions

8
Q

What do the antibodies in pemphigus vulgaris attack?

A

Desmosomes

9
Q

What are gap junctions?

A

Channel proteins composed of connexons that allow electrical and chemical communication between cells

10
Q

How do you diagnose atopic dermatitis?

A

Clinically–some may have increased IgE and eosinophilia, but not all

11
Q

What is the pharmacotherapy for atopic dermatitis?

A

Topical corticosteroids

tacrolimus for more severe

12
Q

What is the general care for atopic dermatitis?

A

Goal is to break the itching and scratching cycle. Use gentle soaps and moisturize after bathing, avoid irritants, and use antihistamines to control pruritus.

13
Q

What type of hypersensitivity reaction is contact dermatitis?

A

4

14
Q

What are the common things that can cause contact dermatitis?

A

Ni
Poison ivy
Perfumes
Neomycin

15
Q

What is the metal that can cause contact dermatitis?

A

Ni

16
Q

What is the abx that can cause contact dermatitis?

A

Neomycin

17
Q

What type of hypersensitivity reaction is latex allergy?

A

Type 1

18
Q

What is erythema toxicum neonatorum, and what is the prognosis?

A

Eczema like rash that begins 1-3 days after delivery. Presents with red papules, pustules, and/or vesicles with surroundings halos

Benign

19
Q

What is the size of a macule?

A

Less than 1 cm

20
Q

What is the size of a patch?

A

Macule that is more than 1 cm

21
Q

What is the size of a papule?

A

Less than 1 cm

22
Q

What is a plaque?

A

Papule more than 1 cm

23
Q

What is the larger form of a vesicle?

A

bulla

24
Q

What is a wheal?

A

Transient smooth papule or plaque

25
Q

What is the MOA of a type I hypersensitivity rxn?

A

Antigen crosslinks IgE on mast cells, causing release of histamine and other vasoactive amines

26
Q

What is the MOA of a type II hypersensitivity rxn?

A

Cytotoxic–IgM and IgG bind to antigen on an enemy cell, leading to lysis by complement activation or phagocytosis

27
Q

What is the MOA of a type III hypersensitivity rxn?

A

Immune complex deposition leading to PMN activation

28
Q

What is the MOA of serum sickness?

A

Antibodies to the foreign proteins are produced in ∼ 5 days. Immune complexes form and are deposited in membranes, where they lead to tissue damage by fixing complement.

29
Q

What is an arthus reaction?

A

A local reaction to antigen by preformed antibodies characterized by vascular necrosis and thrombosis.

30
Q

What is the MOA of a type IV hypersensitivity rxn?

A

Sensitized T lymphocytes kill

31
Q

How do you definitively diagnose contact dermatitis?

A

Patch testing

32
Q

What is the treatment for contact dermatitis?

A

Topical corticosteroids and allergen avoidance

33
Q

What is seborrheic dermatitis?

A

Chronic inflammatory skin disease that may be caused by a rxn to malassezia furfur

Presents in seborrheic regions

34
Q

What is “Cradle cap”?

A

Seborrheic dermatitis of the neonate

35
Q

What are the two major ways that seborrheic dermatitis presents in the neonate?

A

Red diaper rash with yellow scales, erosions, and blisters

36
Q

What are the two major diseases associated with seborrheic dermatitis?

A

PD

AIDS

37
Q

How do you diagnose seborrheic dermatitis?

A

Clinically

38
Q

What is the treatment for seborrheic dermatitis?

A

Selenium sulfide or zinc pyrithione shampoos

39
Q

What is stasis dermatitis?

A

Lower extremity dermatitis due to venous HTN forcing blood from the deep to the superficial venous system

40
Q

What is the treatment for stasis dermatitis to prevent stasis ulcers?

A

Leg elevation

Compression stockings

41
Q

What is the effect of sunlight on seborrheic dermatitis?

A

Exacerbates it

42
Q

What is psoriasis?

A

T cell mediated inflammatory dermatosis characterized by erythematous plaques with silvery scales

43
Q

What areas of the body are affected by psoriasis?

A

Extensor surfaces

44
Q

Rash that affects the flexural surfaces? Extensor surfaces?

A
Flexural = atopic dermatitis
Extensor = psoriasis
45
Q

What are the labs that should be obtained prior to starting methotrexate, or anti-TNF biologics?

A

CBC
CMP
Hepatitis
PPD

46
Q

What is the a Auspitz sign?

A

Pinpoint bleeding when a scale is scraped

47
Q

Sausage digits = ?

A

Psoriatic arthritis

48
Q

How do you definitively diagnose psoriasis?

A

bx

49
Q

Munro microabscesses on histology =?

A

Psoriasis

50
Q

erythematous plaques with silvery scales = ?

A

Psoriasis

51
Q

What is the treatment for psoriasis? (3)

A

Topical steroids

Methotrexate or anti-TNF biologics

52
Q

Why is UV light contraindicated as a treatment for psoriasis in immunosuppressed patients?

A

Cancer

53
Q

What is the pathophysiology of urticaria?

A

the release of histamine and prostaglandins from mast cells in a type I hypersensitivity response.

54
Q

What is the duration of urticaria?

A

Up to 6 weeks in some cases

55
Q

What are the lesions of urticaria?

A

Wheals of reddish or white transient papules or plaques representing dermal edema

56
Q

What are the extracutaneous manifestations of urticaria?

A

Angioedema
Asthma
GI s/sx
Joint swelling

57
Q

How do you diagnose urticaria?

A

H&P

58
Q

What is the treatment for urticaria?

A

Systemic antihistamines

59
Q

What is the most common skin reaction to a drug?

A

Mild morbilliform rash that is widespread, symmetric, and pruritic

60
Q

Which type of hypersensitivity reaction can drugs cause?

A

All types

61
Q

How long does it take for a patient to react to a drug?

A

7-14 days

62
Q

True or false: If a patient reacts within 1–2 days of starting a new drug, it is probably not the causative agent.

A

True

63
Q

What usually triggers erythema multiforme?

A

HSV or mycoplasma

64
Q

What is the treatment for a cutaneous drug reaction?

A

antihistamines and topical steroids

65
Q

What are the characteristics of the lesions with erythema multiforme?

A

Targetoid lesions

66
Q

True or false: the palms and soles are usually spared with erythema multiforme?

A

False–often affected

67
Q

What is the difference between erythema multiforme major and minor?

A

Major involves mucosal surfaces

68
Q

How can you differentiate erythema multiforme vs SJS or TEN?

A

Nikolsky sign negative for EM

69
Q

What is the treatment for erythema multiforme?

A

Supportive

70
Q

What is the role of steroids in the treatment for erythema multiforme?

A

Of no benefit

71
Q

What is the difference between SJS and TEN?

A

SJS is less than 10% of body surface

TEN is more than 30%

72
Q

What is the nikolsky sign?

A

Finger pressure on the skin results in sloughing off of the skin

73
Q

What is the histological difference between SJS and TEN?

A

SJS shows degeneration of the basal layer of the epidermis, whereas TEN reveals a full thickness eosinophilic epidermal necrosis

74
Q

What is the treatment for SJS/TEN?

A

Thermoregulatory and electrolyte disturbance correction

75
Q

What are the causes of erythema nodosum?

A
NO cause
Drugs
OCPs
Sarcoidosis
Ulcerative colitis
Microbiology

(NODOSUM)

76
Q

What is panniculitis?

A

Inflammatory process of the SQ adipose tissue

77
Q

What is the presentation of erythema nodosum?

A

Painful, erythematous nodules that appear on the patient’s anterior shins that eventually turn brown or gray

78
Q

Patient with erythema nodosum will often test positive for what infectious agent?

A

VDRL (like SLE)

79
Q

How do you workup erythema nodosum? (3)

A

ASO titer
PPD
CXR to r/o sarcoidosis

80
Q

What is the treatment for erythema nodosum?

A

NSAIDs and cool compresses

KI for persistent cases

81
Q

Which is an intraepidermal lesion, and which along the BM: bullous pemphigoid vs pemphigus vulgaris?

A
Intraepidermal = pemphigus vulgaris
BM = bullous pemphigoid
82
Q

What are the antibodies directed against in bullous pemphigoid vs pemphigus vulgaris?

A
BP = hemidesmosomes
PV = desmoglein
83
Q

Compare the appearance of the blisters in bullous pemphigoid vs pemphigus vulgaris.

A
BM = firm, stable blisters preceded by urticaria
PV = Erosions more common than intact blisters
84
Q

Which is nikolsky sign positive: bullous pemphigoid vs pemphigus vulgaris?

A

PV = positive

85
Q

Which has mucosal involvement: bullous pemphigoid vs pemphigus vulgaris

A

PV

86
Q

What is the age of onset for bullous pemphigoid vs pemphigus vulgaris?

A

BP = over 60

PV 40-60

87
Q

What is the treatment for bullous pemphigoid vs pemphigus vulgaris?

A

Steroids for BP

Steroids and immunosuppressants for PV

88
Q

Which has a higher chance of mortality: bullous pemphigoid vs pemphigus vulgaris

A

PV (super rare to die from BP)

89
Q

What is the best way to diagnose HSV infection?

A

viral culture of the lesions

90
Q

Where are the lesions of dermatitis herpetiformis usually found?

A

elbows, knees, buttocks, and neck

91
Q

When should patient with a primary outbreak of HSV be given acyclovir?

A

Within 72 hours of onset

92
Q

When is daily prophylaxis indicated for HSV?

A

More than 6 outbreaks per year

93
Q

HSV infection lasting longer than how long is considered an AIDS defining illness?

A

1 month

94
Q

What are the lesions like with VZV?

A

evolving from red macules to vesicles that then crust over.

95
Q

What is the difference in lesions between smallpox and varicella?

A

Smallpox has lesions that are all at the same stage, whereas VZV has lesions all at different stages

96
Q

What are the meds that are used for pain control for VZV?

A

Gabapentin

TCAs

97
Q

What is the post exposure prophylaxis with VZV?

A

Rarely needed as most patients in the United States have been vaccinated or had childhood varicella. If needed, immunocompromised individuals, pregnant women, and newborns should receive varicella-zoster immune globulin within 10 days of exposure. Immunocompetent adults should receive a varicella vaccine within 5 days of exposure.

98
Q

What type of virus is molluscum contagiosum?

A

Poxvirus

99
Q

How is molluscum contagiosum spread?

A

Skin-skin contact, or towel sharing

100
Q

True or false: mollusscum contagiosum usually spares the palms and soles

A

True

101
Q

What are the histological findings of molluscum contagiosum?

A

Inclusion bodies

102
Q

What is the treatment for molluscum contagiosum?

A

Local destruction

Resolve spontaneously

103
Q

True or false: impetigo can lead to acute glomerulonephritis

A

True

104
Q

What is the treatment for mild impetigo?

A

Topical abx

105
Q

What is the treatment for severe impetigo caused by MRSA? If not caused?

A
MRSA = TMp-SMX
Not = cephalexin, dicloxacillin
106
Q

What is the treatment for cellulitis?

A

Use 5–10 days of oral antibiotics. IV antibiotics are used if there is evidence of systemic toxicity, comorbid conditions, diabetes mellitus (DM), extremes of age, or hand or orbital involvement. Antibiotic choices similar to impetigo.

107
Q

What is the classic rash associated with scarlet fever?

A

Rose spots on the abdomen

108
Q

What is the treatment for salmonella typhi?

A

Fluoroquinolones

109
Q

What is the presentation of scarlet fever?

A

sandpaper rash + strawberry tongue

110
Q

What is the treatment for scarlet fever?

A

PCN

111
Q

What is/are the infectious agent(s) that cause necrotizing fasciitis?

A

S aureus
E.coli
Clostridium perfringens

112
Q

What is the presentation of nec fas?

A

Quickly moving erythema that becomes dusky or purplish as it progresses. initially painful, followed by anesthesia in necrotic areas

113
Q

What is Ludwig’s angina?

A

bilateral cellulitis of the submental, submaxillary, and sublingual spaces that usually stems from an infected tooth

114
Q

How does Ludwig’s angina usually present?

A

Dysphagia
Drooling
Fever

115
Q

What is the treatment for nec fas?

A

Broad spectrum abx + surgical debridement

116
Q

What bacteria usually cause folliculitis?

A

Staph
Strep
Gram - bacteria

117
Q

What is a furuncle?

A

hair follicle abscess

118
Q

What is a carbuncle?

A

Collection of furuncles

119
Q

If eosinophilic folliculitis is suspected, what can be used to confirm the diagnosis?

A

Bx with KOH prep

120
Q

What are the abx that cause sun sensitivity?

A

Tetracycline and doxycycline

121
Q

What is the treatment for mild acne?

A

Topical retinoids

122
Q

What is the treatment for moderate-severe acne?

A

doxycycline or minocycline.

Oral retinoids

123
Q

What are the labs that need to be followed with retinoids?

A

LFTs
Cholesterol
Triglycerides

124
Q

What diseases are risk factors for the development of tinea versicolor?

A

Cushing’s

Immunosuppression

125
Q

What is the test for tinea versicolor?

A

KOH prep showing spaghetti and meatball appearance

126
Q

When are abx needed in the treatment of a pilonidal cyst?

A

If cellulitis is present

127
Q

What are the two treatments for tinea versicolor?

A

Ketoconazole or selenium sulfide

128
Q

Where anatomically does candida usually present?

A

Skin folds and moist areas

129
Q

How does skin candidiasis present?

A

markedly erythematous patches with occasional erosions and smaller satellite lesions

130
Q

What is the treatment for oral candida?

A

Oral fluconazole

Nystatin swish and swallow

131
Q

What is the treatment for a diaper rash 2/2 candida?

A

Topical nystatin

132
Q

What is the treatment for superficial candidiasis?

A

Topical antifungals

133
Q

Dermatophytes only live in what type of tissue?

A

keratinized tissues

134
Q

What are the top three dermatophytes?

A

Trichophyton
Microsporum
Epidermophyton

135
Q

loss. A large inflammatory boggy mass caused by tinea capitis is called what?

A

A kerion

136
Q

Which tinea needs to be treated systemically? Why?

A

Tinea capitis to penetrate into hair follicles

137
Q

What is the treatment for head lice?

A

Permethrin
Pyrethrin
Benzyl alcohol

138
Q

What is the treatment for body lice?

A

Wash clothes and sheets thoroughly

139
Q

What is the treatment for pubic lice?

A

Same as head lice (permethrin)

140
Q

What are the characteristics of the lesions with scabies?

A

linear tracks, which represent the burrows of the mite

141
Q

What is the most commonly affected site for scabies lesions?

A

interdigital finger webs

142
Q

When is the itching worse with scabies?

A

After hot showers and at night.

143
Q

What is the treatment for scabies?

A

Permethrin from the neck down

oral ivermectin

144
Q

What is the pathophysiology of decubitus ulcers?

A

Chronic pressure restricts microcirculation

145
Q

What is the low grade and high grade decubitus ulcers?

A

Low grade = wound care

High grade = surgical debridement

146
Q

What are the three types of gangrene?

A

Dry
Wet
Gas

147
Q

What is the cause of dry gangrene?

A

Due to insufficient blood flow, typically from atherosclerosis

148
Q

What is the causative agent of gas gangrene?

A

C perfringens infection

149
Q

What are the s/sx of dry gangrene?

A

Dull ache, and pallor that progresses to bluish-black

150
Q

What is the appearance of wet gangrene?

A

Tissue appears bruised, swollen or blistered with pus

151
Q

What is the treatment for gangrene?

A

Surgical debridement (gas gangrene is an emergency)

152
Q

Why are abx not sufficient to treat gangrene?

A

Poor blood flow to the wound

153
Q

What, in addition to emergency surgical debridement, can be done for gas gangrene?

A

Hyperbaric oxygen

154
Q

What is acanthosis nigricans? What is the treatment?

A

Intertriginous zones become hyperkeratotic and hyperpigmented

Not treated–encourage weight loss

155
Q

What will an x-ray show with gas gangrene?

A

Bubbles of air in soft tissue

156
Q

What is lichen planus?

A

A self-limited, recurrent, or chronic inflammatory disease affecting the skin, oral mucosa, and genitalia.

157
Q

What are the 6’s of lichen planus?

A
Planar
Purple
Polygonal
Pruritic
Papules
Plaques
158
Q

What infectious agent is associated with lichen planus?

A

HCV

159
Q

What is the natural history of lichen planus?

A

Purplish, pruritic plaques that demonstrate the koebner phenomenon

160
Q

What is the treatment for lichen planus?

A

Topical corticosteroids

161
Q

What is rosacea?

A

Chronic disease of pilosebaceous units, characterized by central facial erythema with telangiectasias

162
Q

What does longstanding rosacea progress to?

A

Rhinophyma

163
Q

Who usually gets rosacea?

A

Middle aged women with fair skin

Usually have an abnormal flushing response to hot drinks

164
Q

What is the treatment for rosacea?

A

metronidazole

165
Q

What is pityriasis rosea?

A

Idiopathic dermatitis (possible 2/2 HHV 7 infx)

166
Q

What is the natural history of pityriasis rosea?

A

Herald patch days to weeks before outbreak of multiple papules and plaques with a fine (“cigarette paper”) feeling in a tree like pattern

167
Q

What is the feeling of pityriasis rosea commonly likened to?

A

Cigarette paper

168
Q

What is the treatment for pityriasis rosea?

A

Supportive (antipruritics, lubrication, antihistamines)

169
Q

What is vitiligo?

A

Acquired loss of function or absence of melanocytes

170
Q

What is the treatment for vitiligo?

A

Topical steroids

171
Q

How can you confirm vitiligo?

A

Serological markers of autoimmune disease

172
Q

What are xanthelasmas?

A

Soft, yellow plaques seen on the medial aspects of the eyelids bilaterally, associated with hyperlipidemia

173
Q

What is a hordeolum?

A

Painful acute eyelid gland infection (stye) usually caused by staph aureus

174
Q

What is a chalazion?

A

A self-limited, recurrent, or chronic inflammatory disease affecting the skin, oral mucosa, and genitalia.

175
Q

What are the characteristics of seborrheic keratoses? What is their malignant potential?

A

Stuck on appearance with a sandpaper like texture

Totally benign

176
Q

What is the appearance of actinic keratoses?

A

flat areas of erythema and scale

177
Q

Why should actinic keratoses be treated? How are they treated?

A

Risk of progression to SCC

Cryosurgery or 5FU

178
Q

What are marjolin’s ulcers?

A

SCC that arises from site of drainage or burns

179
Q

Ar exposure can cause SCC in what anatomic distribution?

A

palmoplantar distribution

180
Q

True or false: BCC has virtually no metastatic potential

A

True

181
Q

What is the inherited disease that predisposes people to melanoma?

A

Familial atypical mole and melanoma syndrome

182
Q

Pruritus in a changing skin lesion is a suspicious feature for what?

A

Malignant change to melanoma

183
Q

What is amelanotic melanomas?

A

Melanomas that present without pigment–hard to identify

184
Q

What is acral lentiginous melanoma?

A

Melanoma that begins on the palms, soles, and nail bed as a slowly spreading, pigmented patch

185
Q

What is lentigo maligna?

A

Melanoma that arises in a solar lentigo. Usually found on sun-damaged skin of the face

186
Q

Diameter greater than what is suspicious for melanoma?

A

6 mm

187
Q

What is the treatment for metastatic melanoma?

A

chemo

188
Q

What infectious disease can mimic the cutaneous lesions of kaposi’s sarcoma?

A

Bartonella henselae

189
Q

What is the causative agent of kaposi’s sarcoma?

A

HHV8

190
Q

What is the treatment for kaposi’s sarcoma 2/2 AIDs?

A

HAART

191
Q

What is the treatment for Kaposi’s sarcoma not 2/2 AIDS?

A

Excise and/or IFN-alpha

192
Q

What is mycosis fungoides?

A

Cutaneous T cell lymphoma–progressive neoplastic proliferation of T cells

193
Q

What are the lesions like with mycosis fungoides?

A

Psoriatic appearing plaques or patches that are often pruritic with a predilection for the trunk an buttocks

194
Q

What is Sezary syndrome?

A

Leukemic phase of cutaneous T cell lymphoma, manifesting as Sezary cells in the peripheral blood

195
Q

How do you diagnose mycosis fungoides?

A

bx showing

196
Q

Dermatitis that is chronic and resistant to treatment should be biopsied for what condition?

A

Mycosis fungoides

197
Q

What is the treatment for mycosis fungoides?

A

Phototherapy