Dermatology, Allergy, and Immunology Flashcards Preview

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Flashcards in Dermatology, Allergy, and Immunology Deck (91):
1

Pathophysiology: Allergic contact dermatitis

Type IV HSR

2

Pathophysiology: Irritant contact dermatitis

Physical or chemical irritation

3

Treatment: Contact dermatitis

Topical corticosteroids

4

Treatment: Comedonal acne

Topical retinoids

If initial therapy fails, add:
salicylic, azelaic, or glycolic acid

5

Treatment: Mild inflammatory acne

Topical retinoids +
Benzoyl peroxide

6

Treatment: Moderate inflammatory acne

Topical retinoids +
Benzoyl peroxide +
Topical antibiotics (erythromycin, clindamycin)

7

Treatment: Severe inflammatory acne

Topical retinoids +
Benzoyl peroxide +
Topical antibiotics (erythromycin, clindamycin) +
Oral antibiotics

8

Treatment: Moderate nodular (cystic) acne

Topical retinoids +
Benzoyl peroxide +
Topical antibiotics (erythromycin, clindamycin)

9

Treatment: Severe nodular (cystic) acne

Topical retinoids +
Benzoyl peroxide +
Topical antibiotics (erythromycin, clindamycin) +
Oral antibiotics

10

Treatment: Unresponsive severe nodular (cystic) acne

Oral isotretinoin

11

___ is a viral infection of the hand caused by HSV.

Most adult infections are acquired from conact with genital herpetic lesions or infected orotracheal secretions.

Sponataneous resolution is the norm but recurrences are common.

Herpetic whitlow

12

___ can cause early perineural invasion, causing regional neurologic symptoms (e.g., numbness, paresthesias)

Squamous cell carcinoma (skin)

13

Risk factors: SCC (skin)
[5]

Sunlight exposure
Fair skin
Chronic inflammation or scar formation
Ionizing radiation exposure
Immunosuppressive therapy *

14

___ is the MC skin malignancy in patients on chronic immunosuppressive therapy for a history of organ transplant.

In immunosuppressed patients, it is more aggressive, with an increased risk of local recurrence and regional metastasis.

Squamous cell carcinoma (SCC)

15

___ is the most common skin malignancy in the general population.

Basal cell carcinoma (BCC)

16

Multiple, discrete, flesh- to red-colored papules of varying size with slight central umbilication.

Usually seen in immunosuppressed patients.

Disseminated cryptococcus

17

___ and ___ predispose patients to shingles.

Increased age
Immunocompromised status

18

Treatment: Shingles (Herpes Zoster)

Decreases duration of symptoms and incidence of post-herpetic neuralgia, especially if initiated within 72 hours of the onset of symptoms.

VALACYCLOVIR
Acyclovir
Famciclovir

19

Treatment: Tinea corporis

Topical antifungals (clotrimazole, terbinafine)

20

Presents with widely scattered, erythematous, scaly papules and plaques.

Typically follows a streptococcal infection but can also occur in patients with RA, especially those on TUMOR NECROSIS FACTOR-ALPHA INHIBITORS.

Guttate psoriasis

21

Treatment: Guttate psoriasis

UV phototherapy
Topical glucocorticoids
Vitamin D analogs

22

Well-circumscribed and raised erythematous plaques with a central pallor, along with intense pruritus and resolution of individual skin lesions within 24 hours.

Etiology:
Infections
NSAIDs
IgE-mediated (antibiotics, insect bites, latex, food)
Direct mass cell activation (narcotics, contrast medium)
Idiopathic (50%)

Urticaria (acute and chronic)

23

Acute urticaria = ___
Chronic urticaria = ___

Acute <6 weeks
Chronic >6 weeks

24

Seborrheic dermatitis is associated with nervous system disorders (especially ___) and ___.

Parkinson disease
HIV

25

Treatment: Seborrheic dermatitis

Topical antifungal agents:
Ketoconazole
Selenium sulfide

26

___ causes pruritic, erythematous plaques with a greasy scale that predominantly affect the scalp and face.

It is most common in the first year of life and in middle age and can be associated with Parkinson disease and HIV.

TX: Topical antifungals (ketoconazole, selenium sulfide)

Seborrheic dermatitis

27

___ is characterized by erythema, edema, and telangiectasias affecting primarily the central face.

Flushing and local discomfort can be triggered by hot or spicy foods, emotional stressors, or temp flucuations.

Rosacea

28

___ presents with well-circumscribed plaques covered with a thick, silvery scale.

The lesions are typically worst at the extensor surfaces of the elbows and knees, but may also affect the scalp and trunk.

Psoriasis

29

___ is characterized by hypopigmented, hyperpigmented, or erythematous macules or patches on the upper body.

It is caused by Malassezia spp. yeast and is often most visible after extensive sun exposure due to tanning of adjacent skin.

Pityriasis versicolor

30

___ is a chronic, relapsing condition characterized by inflammatory occlusion of folliculopilosebaceous units.

It typically occurs in intertriginous skin areas and presents as painful nodules that can progress to abscesses that open to the skin surface.

Complications: Sinus tracts, comedones, scarring

Hidradenitis suppurativa

31

Skin conditions and associated diseases:
Acanthosis nigricans

Insulin resistance
GI malignancy

32

Skin conditions and associated diseases:
Multiple skin tags

Insulin resistance
Pregnancy
Crohn disease (perianal)

33

Skin conditions and associated diseases:

Porphyria cutanea tarda

Cutaneous leukocytoclastic vasculitis (palpable purpura) secondary to cryglobulinemia

Hepatitis C

34

Skin conditions and associated diseases:
Dermatitis herpetiformis

Celiac disease

35

Skin conditions and associated diseases:

Sudden-onset severe psoriasis

Recurrent herpes zoster

Disseminated molluscum contagiosum

HIV infection

36

Skin conditions and associated diseases:
Severe seborrheic dermatitis

HIV infection
Parkinson disease

37

Skin conditions and associated diseases:
Explosive onset of multiple itchy, seborrheic keratoses

GI malignancy

38

Skin conditions and associated diseases:
Pyoderma gangrenosum

Inflammatory bowel disease (IBD)

39

Niacin deficiency presents with [5]

Dermatitis
Diarrhea
Neurologic symptoms (insomnia, dementia, confusion)
Erythematous tongue
Vomiting

40

___ is characterized by symmetrical, hyperpigmented, velvety plaques in the axilla, groin, and neck.

It is associated with ___ in younger patients and ___ in older patients.

Acanthosis nigricans

Insulin resistance (DM, PCOS)

GI malignancy

41

Presentation:
Acute, diffuse, non-inflammatory hair loss
Scalp and hair fibers appear NORMAL
Hair shafts easily pulled out (hair pull test)

Triggers:
Severe illness, fever, surgery
Pregnancy, childbirth
Emotional distress
Endocrine and nutritional disorders

Management:
Address underlying cause
Reassurance (self-limited)

Telogen effluvium

42

___ is an autoimmune disorder characterized by circumscribed patches of hair loss. Hair shafts show narrowing close to the surface and may be broken off.

Alopecia areata

43

___ causes uneven hair loss in a characteristic pattern

Men - thinning at the frontotemporal hairline and vertex

Women - thinning at the vertex and sides with preservation of the hairline

Androgenetic alopecia

44

___ is characterized by fragility of hair with breaking of strands. It can be congenital or acquired (e.g., excessive heat, hair dyes, salt water). Close inspection shows fractures strands with splitting of fibers.

Trichorrhexis nodosa

45

Plantar wars are due to ___ infection and most commonly occur in young adults and immunocompromised individuals. The lesions appears as hyperkeratotic papules on the sole of the foot that can be painful when walking or standing.

Human papillomavirus (HPV)

46

Lichen planus tetrad

Flat-topped Purple Papules or Plaques
Pruritic
Planar
Polygonal

47

___ usually appears after age 50 as a solitary or multiple well-circumscribed hyperpigmented lesions. They can have a "stuck-on" or warty appearance and usually occur on the trunk, face, and upper extremities.

Seborrheic keratosis (SK)

48

Pathogenesis:
Sarcoptes scabiei mite infestation
Spread by direct person-to-person contact

Presentation:
Extremely pruritic pathognomonic burrows and small, erythematous papules
Rash located on interdigital web spaces, flexor wrists, extensor elbows, axillae, umbilicus and genitalia

Treatment:
___ or ___

Scabies

Topical 5% Permethrin

Oral Ivermectin

49

___ bites often cause small, punctate lesions with surrounding erythema; classically in linear tracks or clusters.
Bites on palms and soles are uncommon due to thickness of skin.

Bed bug

50

Nodular basal cell carcinoma has low metastatic potential but should be removed with either electrodessication and curettage (ED&C) or surgical excision. ___, in which thin layers are removed and inspected microscopically to ensure clear margins, is used for high-risk lesions in delicate or cosmetically sensitive areas.

Mohs micrographic surgery

51

Low-risk superficial BCC may be managed with topical therapy using either ___ or ___. These agents may also be used in field therapy for patients with MULTIPLE ACTINIC KERATOSES.

5-FU
Imiquimod

52

Scaly, erythematous, pruritic patch with centrifugal spread.

Subsequent central clearing with raised annular border.

Tinea corporis (ringworm)

53

Treatment: Tinea corporis

First-line: Topical antifungals (clotrimazole, terbinafine)

Second-line: Oral antifungals (terbinafine, griseofulvin)

54

Most common dermatophyte that causes Tinea Corporis (ringworm)

Trichophyton rubrum

55

DX: Tinea corporis

KOH prep of skin scrapings

56

___ is an inflammatory disorder characterized by erythematous papules and plaques that evolve into target lesions. It is often associated with a recent HSV infection.

Erythema multiforme (EM)

57

___ is a benign bodule containing squamous epithelium that produces keratin.

It presents as a dome-shaped, firm, freely moveable cyst or nodule with a small central punctum.

The lesion can remain stable or gradually increase in size but may produce a cheesy white discharge.

Usually resolves spontaneously, but can recur.

Epidermal inclusion cyst

58

A benign fibroblast proliferation that typically appears as a firm, hyperpigmented nodule, most often on the lower extremities.

Have a fibrous component that causes dimpling in the center when the area is pinched (dimple or buttonhole sign).

Dermatofibroma

59

Treatment: SJS

Supportive with aggressive fluid support and wound care similar to that for burns

60

___ associated with hepatitis C is due to immune complex deposition in small blood vessels, leading to endothelial injury and end-organ damage.

Typical manifestations:
Palpable purpura
Arthralgias
Glomerulonephritis

Mixed cryoglobulinemia

61

Presentation:
Blisters, bullae, scarring, hypo/hyperpigmentation on sun-exposed skin (back of hands, forearms, face)
Scarring and calcification similar to scleroderma

Associated conditions:
HCV
HIV
Excessive alcohol consumption
Estrogen use
Smoking

Diagnostic testing:
Mildly elevated LFTs and iron overload
Elevated plasma or urine porphyrin levels

Porphyria cutanea tarda

62

___ are the MCC of acquired angioedema.

ACE inhibitors

63

Aspirin and NSAIDs can cause ___, which typically happens IMMEDIATELY after exposure and is accompanied by itching and skin rash (urticaria).

Allergic angioedema

64

Pressure ulcer staging:
Intact skin
Non-blanchable with localized redness

Stage 1

65

Pressure ulcer staging:
Shallow, open ulcer
Red-pink wound with no sloughing
Possible intact or ruptured blister

Stage 2

66

Pressure ulcer staging:
Full-thickness skin loss with possible visible subcutaneous fat
No exposed bone, tendon, or muscles

Stage 3

67

Pressure ulcer staging:
Full-thickness skin loss
Exposed bone, tendon, or muscle

Stage 4

68

Pressure ulcer staging:
Full-thickness skin loss
Ulcer base covered by slough and/or eschar that needs removal to stage

Unstageable

69

Risk factors for pressure ulcers include [5]

Decreased mobility
Malnutrition
Abnormal mental status
Decreased skin perfusion
Reduced sensation

70

Interventions that can prevent pressure ulcers include [5]

Proper positioning for PRESSURE REDISTRIBUTION
Mobilization
Careful skin
Moisture control
Maintenance of nutrition

71

___ are useful in the prevention and management of venous insufficiency ulcers, which usually occur in the setting of venous stasis dermatitis.

Compression stockings

72

___ are used to prevent DVT in patients with contraindications to anticoagulant therapy.

Intermittent pneumatic compression devices

73

A chronic, inherited skin disorder characterized by DIFFUSE DERMAL SCALING.

Skin appears dry and rough with horny plates resembling fish or reptile scales.

Mutation: Filaggrin gene

Treatment includes:
Emollients
Keratolytics (coal tar, salicylic acid)
Topical retinoids

Ichthyosis vulgaris

74

___ is an acute skin infection caused by Staphylococcus and Streptococcus spp. and is characterized by erythematous papules, vesicles, and/or pustules with honey-colored crusting.

Impetigo

75

___ presents with ecchymoses in elderly patients in areas exposed to repeated minor trauma (extensor surfaces of hands/forearms).

It is due to age-related loss of elastic fibers in perivascular connective tissue.

Not dangerous and requires no further workup.

Senile purpura

76

SCC is not usually metastatic at the time of diagnosis, but SCC arising in a wound or burn (termed a ___) is associated with an increased risk of metastasis.

Margolin ulcer

77

___ are used for symptomatic keloids, which may form in the setting of an established scar.

Intralesional glucocorticoids

78

SCC in situ

Bowen disease

79

___ is the most common vaccine-preventable disease among travelers.

Hepatitis A

80

The CDC recommends that those traveling to North Africa, administration of the following vaccines should be administered [4]

Hepatitis A
Hepatitis B
Typhoid
Polio booster

81

Toxicodendron (formerly Rhus) species (poison ivy/oak/sumac) can grow as small shrubs or vines and produce ___, a highly allergenic resin that causes allergic contact dermatitis.

Urushiol

82

___ is a fungal infection acquired by direct traumatic inoculation of the skin. It is characterized by ulcerating, pustular nodules at the site of inoculation and associated lymphatic channels.

Sporotrichosis

83

Short-term and long-term management of DERMATITIS HERPETIFORMIS.

Short-term: Dapsone

Long-term: Gluten-free diet

84

Skin biopsy of dermatitis herpetiformis shows ___ at the tips of the dermal papillae.

Subepidermal microabscesses

85

Immunofluorescence studies in dermatitis herpetiformis shows deposits of ___ in the dermis.

Anti-epidermal transglutaminase IgA

86

___ is an autoimmune bliastering disease that causes pruritic, tense bullae in the flexural surfaces, groin, and axilla.

Mucosal lesions occur in only a minority of patients.

Biopsy shows subepidermal cleavage, with linear IgG deposits at the BM on IF studies.

Bullous pemphigoid

87

___ is a blistering condition caused by S. aureus.

Lesions may appear as macules, vesicles, bullae, and honey-colored crusts, which leave red denuded areas when removed.

Bullous impetigo

88

___ is a mucocutaneous blistering disease characterized by flaccid bullae and mucosal erosions.

Caused by autoantibodies against desmogleins, which are involved in adherence between epidermal keratinocytes.

Biopsy shows INTRAepidermal cleavage.

IF studies show INTERcellular IgG deposits in the epidermis.

Pemphigus vulgaris

89

First-line treatment for BULLOUS PEMPHIGOID is ___, which is effective even for extensive disease.

High-potency topical glucocorticoid (CLOBETASOL)

90

Treatment: Rosacea

Topical metronidazole (gel form) - several months
Systemic antibiotics (tetracycline) - maintenance
Isotretinoin - refractory

91

Sudden-onset of multiple SKs, possibly indicating an occult internal malignancy.

Leser-Trelat sign