Acne, Rosacea and Disorders of Sebaceous and Sweat Glands MCQs

Dermatology · 14 free questions with answers & explanations.

1. Isotretinoin (13-cis retinoic acid) is the only drug that addresses all four pathogenic factors in acne vulgaris. Its PRIMARY mechanism of action in acne is:
2. A 38-year-old woman presents with central facial erythema, telangiectasias, papulopustules and episodic flushing for 2 years. She has no comedones. Her nose shows phymatous skin thickening. Which subtype of rosacea is she MOST likely in?
3. Hidradenitis suppurativa (HS) affects apocrine-bearing skin. The HURLEY staging system classifies HS into three grades. A patient with multiple interconnected sinus tracts and scarring diffusely throughout the axilla without clear areas of normal skin would be classified as:
4. A 16-year-old boy has severe nodulocystic acne on the trunk and face with multiple hypertrophic scars. He has been on oral doxycycline and topical tretinoin for 4 months with minimal improvement. What is the most appropriate next step in management?
5. Rosacea subtypes include erythematotelangiectatic, papulopustular, phymatous, and ocular variants. Which organism's eradication with oral ivermectin has shown efficacy specifically for the papulopustular subtype?
6. Fox-Fordyce disease is a disorder of which adnexal structure, and what is its characteristic histological finding?
7. In acne vulgaris, the comedogenic action of Cutibacterium acnes on sebum is primarily mediated through which mechanism that drives inflammation?
8. A 24-year-old woman with severe nodular acne on face and trunk was recently started on isotretinoin 0.5 mg/kg/day. At her 4-week visit she returns with a dramatic worsening — numerous inflamed nodules, cysts, and sinuses are forming with crusting. This phenomenon is known as:
9. A 45-year-old woman presents with persistent central facial erythema, flushing triggered by hot beverages and sun exposure, papules and pustules on the cheeks and nose, and telangiectases. She has no comedones. Demodex mite density is elevated on skin scraping. Which topical agent directly targets Demodex folliculorum and is approved for rosacea?
10. A patient presents with tender, draining sinuses and abscesses in the axillae and groin bilaterally, with ropelike scarring from prior episodes. He has smoked for 15 years. Hurley stage III is assigned. What is the mechanism underlying this condition and the best treatment for Hurley stage III?
11. A 22-year-old male with severe nodulotubercular acne develops tender lymphadenopathy, fever, and arthralgia in addition to his acne lesions. He also has palmoplantar keratoderma. The most likely diagnosis is:
12. Regarding the mechanism of action of topical azelaic acid in acne and rosacea, which statement is CORRECT?
13. Rosacea is characterised by all of the following EXCEPT:
14. Hidradenitis suppurativa (HS) is classified by the Hurley staging system. A patient with multiple interconnected sinus tracts and scarring over both axillae with no areas of normal skin represents: