Hair/skin/nails

Question 1

What diseases can seborrheic dermatitis be associated with?

Answer 1

Central nervous system disorders (especially Parkinson’s) and HIV

Question 2

What do keratoacanthomas look like?

Answer 2

Dome-shaped nodules with a central keratinous plug. Usually benign but can do malignant transformation

Question 3

What is the appearance and features of actinic keratosis?

Answer 3

Pre-malignant lesion characterized by dry, scaly, flat papules with an erythmatous base, most commonly seen in sun-exposed areas

Question 4

What is an acrochordon?

Answer 4

Skin tag

Question 5

What is pathergy?

Answer 5

Exaggerated ulcerating skin response to minor injuries (e.g. needlestick). Seen in Behçet syndrome

Question 6

What is ichthyosis vulgaris?

Answer 6

A chronic, inherited skin disorder characterized by diffuse dermal scaling (dry, rough skin)

Question 7

What is porphyria cutanea tarda?

Answer 7

Fragile, photosensitive skin that develops vesicles and bullae with trauma or sun exposure (e.g. on dorsa of the hands). Hep C is strongly associated with the condition. Diagnosis is supported by increased plasma and urine porphyrins. Tx with either serial phlebotomy or hydroxychloroquine

Question 8

What is hidradenitis suppurativa (aka acne inversa)?

Answer 8

Most commonly occurs in intertriginous areas (e.g. axilla, inguinal, perineal areas). Due to chronic inflammation of folliculopilosebaceous units and presents as solitary, painful, inflamed nodules that can last for days to months. Can regress on own or can turn into draining abscesses. Risk factors: smoking, obesity, DM, friction

Question 9

What are complications of hidradentitis suppurativa?

Answer 9

Sinus tracts (risk for abscess formation), comedones, and scarring that can become severe and lead to decreased limb movement

Question 10

What is intertrigo?

Answer 10

Due to infection with Candida and presents as well-defined, erythematous plaques with satellite vesicles or pustules in intertriginous and occluded skin areas

Question 11

What is a furuncle?

Answer 11

A skin abscess, usually cause by Staph aureus

Question 12

What skin changes are seen in lymphedema?

Answer 12

Early: pitting edema (often painful)
Late: firm, thickened skin and nonpitting edema (2/2 deposition of subcutaneous collagen and adipose tissue)

Question 13

What medication is associated with drug-induced acne (monomorphic papules without associated comedones, commonly involving the upper back, shoulders, and upper arms)?

Answer 13

Glucocorticoids

Question 14

What is a common skin manifestation of a glucagonoma?

Answer 14

Necrolytic migratory erythema: erythematous papules/plaques on face, perineum, and extremities. Lesions enlarge and coalesce over 7-14 days with central clearing and blistering, crusting and scaling borders

Question 15

What are the three most common etiologies of digital clubbing?

Answer 15

Lung malignancies, cystic fibrosis, and right-to-left cardiac shunts

Question 16

What skin cancer is most associated with immunosuppressive therapy?

Answer 16

Squamous cell carcinoma

Question 17

What are features of bollous pemphigoid?

Answer 17

An autoimmune, blistering skin disorder caused by circulating antibodies against the BP antigen on hemidesmosomes (causes linear IgG deposits along basement membrane). Tense subepidermal blisters develop and can become hemorrhagic or turbid. Peak incidence in people above 60 years of age. Recurrent lesions typically occur in skin flexures (e.g., groin, axilla) and over the abdomen; mucous membranes are usually spared.

Question 18

What are features of pemphigus vulgaris?

Answer 18

An autoimmune, blistering skin disorder caused by circulating antibodies against desmoglein 3 and 1. Painful oral ulcers develop first followed by flaccid intraepidermal blisters on a nonerythematous base. Peak incidence is 30–60 years of age. Recurrent lesions typically occur on the scalp, face, trunk, and regions of pressure, and are associated with a positive Nikolsky sign.

Question 19

What neoplasms is acanthosis nigricans associated with?

Answer 19

Gastrointestinal and genitourinary tract neoplasms

Question 20

What condition is sudden-onset severe psoriasis associated with?

Answer 20

HIV

Question 21

What is the most common cause of erysipelas and lymphangitis?

Answer 21

Step pyogenes

Question 22

What is the most common cause cellulitis?

Answer 22

Staph aureus