A clinical history of discoid or systemic lupus erythematosus may or may not be present.
Most patients are adult females 20 to 60 years old.
Clinical features:
(1) The patient presents with discrete subcutaneous nodules that are erythematous or flesh-colored.
(2) The lesions may be tender.
(3) Lesions are typically seen on the face, shoulders, trunk, breasts, lateral upper arms, buttocks and lateral thighs.
(4) Lesions are only rarely found on distal lower extremities.
Histologic features:
(1) The overlying skin may be normal or may show signs of discoid lupus erythematosus or poikiloderma atrophicans vasculare.
(2) Subcutaneous tissue shows a patchy, lobular lymphocytic infiltrate that may range from light to intense and which are often located adjacent to the septa.
(3) Hyaline necrosis with micropseudocysts is present and surrounded by eosinophilic fibrous tissue.
(4) Lymphocytic vasculitis may be present.
(5) Calcifications in the dermis and subcutaneous fat may be present.
(6) Myxoid change may be present in the dermis.
(7) Immunofluorescence may show immune complexes along the basement membrane at the epidermal-dermal junction or in blood vessels.
