AANP Dermatology 1 — Questions and Answers
Question 1: A patient presents with a well-demarcated, silvery-scaled plaque on the extensor surface of the elbow. What is the most likely diagnosis?
- Atopic dermatitis
- Psoriasis (Correct answer)
- Tinea corporis
- Seborrheic dermatitis
Correct answer: Psoriasis
Psoriasis classically presents as well-demarcated erythematous plaques with silvery scales on extensor surfaces such as the elbows and knees.
Question 2: Which finding is most associated with a melanoma rather than a benign nevus?
- Symmetric shape and uniform color
- Diameter less than 6 mm
- Irregular border and multiple colors (Correct answer)
- Smooth, well-defined margins
Correct answer: Irregular border and multiple colors
The ABCDE criteria for melanoma include Asymmetry, Border irregularity, Color variation, Diameter >6mm, and Evolution—irregular borders and multiple colors are hallmarks.
Question 3: A patient with a history of atopy presents with intensely pruritic, flexural rashes since childhood. What is the most likely diagnosis?
- Contact dermatitis
- Psoriasis
- Atopic dermatitis (eczema) (Correct answer)
- Rosacea
Correct answer: Atopic dermatitis (eczema)
Atopic dermatitis typically begins in childhood, is associated with the atopic triad (asthma, allergic rhinitis, eczema), and preferentially affects flexural areas.
Question 4: What is the first-line treatment for mild-to-moderate acne vulgaris characterized by comedones and a few inflammatory papules?
- Oral isotretinoin
- Topical retinoids and/or benzoyl peroxide (Correct answer)
- Oral doxycycline alone
- Intralesional corticosteroids
Correct answer: Topical retinoids and/or benzoyl peroxide
Topical retinoids normalize follicular keratinization and benzoyl peroxide has antimicrobial properties; both are recommended as first-line agents for mild-to-moderate acne.
Question 5: A patient presents with a target-like skin lesion with central blistering after starting a new antibiotic. What condition should be suspected?
- Urticaria
- Erythema multiforme (Correct answer)
- Fixed drug eruption
- Cellulitis
Correct answer: Erythema multiforme
Erythema multiforme is characterized by target lesions (three concentric zones) and is commonly triggered by HSV infection or medications such as sulfonamides and penicillins.
Question 6: A unilateral, painful, vesicular rash following a dermatomal distribution in an elderly patient is most consistent with:
- Herpes simplex infection
- Herpes zoster (shingles) (Correct answer)
- Contact dermatitis
- Impetigo
Correct answer: Herpes zoster (shingles)
Herpes zoster results from reactivation of varicella-zoster virus in a dorsal root ganglion, presenting as a unilateral vesicular rash in a dermatomal pattern with pain.
AANP Dermatology 1
A patient presents with a well-demarcated, silvery-scaled plaque on the extensor surface of the elbow.
What is the most likely diagnosis?