Apocrine hidrocystoma (AH) is a benign cystic proliferation of apocrine sweat glands that classically presents as a slow-growing nodule on the face, especially in the periorbital region. Histopathological evaluation is required to definitively diagnose an apocrine hidrocystoma. Previous studies have described apocrine hidrocystomas in unusual locations. However, the authors have identified only two reported cases of apocrine hidrocystoma in the postauricular region. We present a third case of a postauricular hidrocystoma in a 26-year-old woman, as well as a brief review of the dermoscopic findings of apocrine hidrocystomas in the existing literature.

The diagnosis of primary systemic amyloidosis, also known as AL (amyloid light-chain) amyloidosis, is often delayed owing to its nonspecific manifestations as well as its rarity. A 64-year-old woman presented with an eight-month history of significant weight loss, anemia, fatigue, and progressive painful cutaneous lesions on her hands, lips, back, perianal, and vulvar area that were originally treated unsuccessfully with antimalarials and systemic corticosteroids. Histopathological examination revealed an amorphous dermis with pale pink material that demonstrated positive birefringence with Congo red staining. Subsequently, the patient underwent a bone marrow biopsy, which uncovered a plasma cell myeloma, the source of her amyloidogenic protein production.

Darier disease (DD), also known as keratosis follicularis or Darier-White disease, is a rare autosomal dominant genodermatosis that presents as hyperkeratotic, warty papules affecting the seborrheic and intertriginous areas. Patients with DD are at risk of secondary infections including the rare complication of Kaposi varicelliform eruption (KVE), a widespread viral infection most commonly caused by herpes simplex virus (HSV). Darier disease with secondary KVE can lead to widespread systemic infection and death. This case report discusses an individual with DD who subsequently developed KVE due to disseminated HSV type 2 infection.