PANRE Dermatology 2 — Questions and Answers
Question 1: A 55-year-old male presents with a pearly, translucent papule with rolled borders and telangiectasias on his nose. What is the most likely diagnosis?
- Squamous cell carcinoma
- Basal cell carcinoma (Correct answer)
- Sebaceous hyperplasia
- Molluscum contagiosum
Correct answer: Basal cell carcinoma
Basal cell carcinoma classically presents as a pearly papule with rolled borders and surface telangiectasias, most commonly on sun-exposed areas.
Question 2: Which topical agent is first-line for treating impetigo in a child with a small, localized area of honey-crusted lesions?
- Topical clindamycin
- Topical mupirocin (Correct answer)
- Topical tretinoin
- Topical hydrocortisone
Correct answer: Topical mupirocin
Topical mupirocin is first-line for localized impetigo caused by Staphylococcus aureus or Streptococcus pyogenes.
Question 3: A 30-year-old woman develops a butterfly-shaped rash across her cheeks and nasal bridge that spares the nasolabial folds. Which test is most specific for confirming systemic lupus erythematosus?
- ANA
- Anti-dsDNA (Correct answer)
- Anti-histone
- Complement C3/C4
Correct answer: Anti-dsDNA
Anti-dsDNA antibodies are highly specific for SLE (>95%) and correlate with disease activity, particularly lupus nephritis.
Question 4: A patient presents with sudden-onset urticaria and angioedema 20 minutes after eating shellfish. Blood pressure is 80/50 mmHg and heart rate is 120 bpm. What is the immediate treatment?
- Diphenhydramine IM 50mg
- Epinephrine 1:1000 IM 0.3mg (Correct answer)
- Methylprednisolone IV 125mg
- Cetirizine PO 10mg
Correct answer: Epinephrine 1:1000 IM 0.3mg
Epinephrine 1:1000 IM (0.3–0.5 mg in the anterolateral thigh) is the first-line treatment for anaphylaxis due to its rapid vasopressor and bronchodilator effects.
Question 5: A 70-year-old man presents with a scaly, erythematous plaque on his lower lip that has been present for 8 months. Biopsy reveals full-thickness dysplasia. What is this condition?
- Actinic cheilitis (Correct answer)
- Leukoplakia
- Lichen planus
- Erythroplakia
Correct answer: Actinic cheilitis
Actinic cheilitis is a premalignant condition caused by chronic UV exposure, presenting as scaly, atrophic changes on the lower lip with risk of SCC transformation.
Question 6: Which finding best distinguishes dermatophyte tinea capitis from alopecia areata in a child?
- Exclamation point hairs
- Positive KOH preparation (Correct answer)
- Nail pitting
- Boggy scalp tenderness
Correct answer: Positive KOH preparation
A positive KOH preparation demonstrating hyphae or spores confirms a dermatophyte infection, definitively distinguishing tinea capitis from alopecia areata.
Question 7: A 25-year-old presents with grouped vesicles on an erythematous base in a dermatomal distribution on the right thorax with pain preceding the rash by 3 days. Which antiviral should be initiated?
- Acyclovir 400mg TID x 5 days
- Valacyclovir 1000mg TID x 7 days (Correct answer)
- Famciclovir 250mg BID x 5 days
- Oseltamivir 75mg BID x 5 days
Correct answer: Valacyclovir 1000mg TID x 7 days
Valacyclovir 1000mg TID for 7 days is preferred for herpes zoster due to better bioavailability and simplified dosing compared to acyclovir.
PANRE Dermatology 2
A 55-year-old male presents with a pearly, translucent papule with rolled borders and telangiectasias on his nose.
What is the most likely diagnosis?