case_images: PMC8450978_01
case_images: Patient with facial lesions consistent with her typical presentation.
case_images: 10.1177_2050313X211046455-fig1.jpg
case_images: PMC8450978_01_10.1177_2050313X211046455-fig1.jpg
case_images: fig1-2050313X211046455
case_images: Pruritic, erythematous, dome-shaped papules with crusting were present diffusely on the patient's back, neck, and face, particularly forehead, perinasal, and periorbital areas (Figure 1).
case_images: (a) Histological finding of initial biopsy showing dense lymphohistiocytic inflammation around the hair follicle. (b) Admixed small histiocytes and lymphocytes were noted with no enlarged cells and no emperipolesis. Immunohistochemistry for dermal-based histiocytes showed (c) increased cytoplasmic staining for S100 and (d) no staining for CD1a. The background epidermal Langerhans cells are positive as internal control for both S100 and CD1a.
case_images: 10.1177_2050313X211046455-fig2.jpg
case_images: PMC8450978_01_10.1177_2050313X211046455-fig2.jpg
case_images: fig2-2050313X211046455
case_images: Initial skin biopsy demonstrated dermal lymphohistiocytic infiltrate with a proposed differential diagnosis including granulomatous rosacea or granulomatous folliculitis (Figure 2(a) and (b)). Immunohistochemistry showed patchy staining for S100 in the histiocytes within the dermis with no staining for CD1a (Figure 2(c) and (d)).