Histology USMLE Step 1 Practice Question
A 16-year-old girl presents to dermatology with a 6-month history of facial acne consisting of comedones, inflammatory papules, and pustules distributed across her forehead, cheeks, and chin. Vital signs are normal. Physical examination reveals open and closed comedones with surrounding erythema and edema. A skin biopsy of an inflamed lesion is obtained. Microscopic examination demonstrates follicular plugging with lamellated keratin, sebaceous gland hyperplasia, and Cutibacterium acnes colonization within the follicle. Serum testosterone and other androgens are within normal limits for her age. Which of the following histopathologic findings is the primary pathogenic mechanism in acne vulgaris?
Answer choices
- ALymphocytic infiltration and granulomatous inflammation in the dermis surrounding the follicle
- BHyperkeratinization of the follicular epithelium with retention of cornified materialCorrect answer
- CVasculitis and endothelial damage within dermal blood vessels adjacent to sebaceous glands
- DFibrosis and permanent loss of dermal collagen architecture
- ESebaceous gland enlargement with increased lipid production independent of androgen sensitivity
- FEpidermal atrophy with thinning of the stratum corneum overlying pilosebaceous units
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