Discoid Lupus Erythematosus

A 38-year-old African-American woman presents with chronic lesions on her cheeks, ears, and scalp. On examination, the structure marked **A** shows well-demarcated erythematous scaly plaques with central atrophic scarring and hypopigmented centers surrounded by hyperpigmented borders. Dermoscopy reveals follicular plugging, and histopathology shows hyperkeratosis with vacuolar interface change at the dermal-epidermal junction. Direct immunofluorescence demonstrates granular IgG and C3 deposition at the DEJ. Which of the following best describes the pathogenic mechanism underlying the erythematous scaly plaques marked **A** in this patient?

A 32-year-old Indian woman presents with a 6-month history of progressive scarring alopecia of the scalp and well-demarcated erythematous plaques on the face and ears. On examination, the plaques show central atrophy with adherent scale that, when lifted, reveals keratotic spikes from follicular ostia. The structure marked **A** in the diagram represents these characteristic scarring photodistributed plaques with follicular plugging. Which of the following statements about the pathogenesis of this lesion is most accurate?

A 31-year-old woman presents with an 18-month history of slowly enlarging, itchy red patches on her cheeks and bridge of the nose, worse after sun exposure. Examination reveals well-demarcated erythematous plaques with central atrophy and hypopigmentation. When the coarse scale overlying each plaque (marked **A** in the diagram) is peeled away, follicular spines are revealed on its undersurface. Skin biopsy confirms chronic cutaneous lupus erythematosus (discoid type). Which of the following best describes the pathologic significance of the adherent keratotic scale marked **A** in establishing this diagnosis?