Anetoderma: An area of slack “baglike” skin due to a local absence or loss of elastic fibers in the skin. The skin affected by anetoderma often occurs in multiple local areas that typically have distinct borders from normal skin (circumscribed). The skin in these areas is soft, thin, and wrinkled, sometimes with patches that bulge out slightly like pouches.
Anetoderma may be primary and occur by itself, or be secondary and occur in association with autoimmune diseases such as systemic lupus erythematosus (SLE) or the antiphospholipid syndrome (APLS). Anetoderma may also be secondary to causes such as syphilis, leprosy, tuberculosis, the drug penicillamine, or premature birth. Anetoderma usually appears sporadically without a family history of the disorder but it can be inherited alone or as part of a syndrome.
The basic pathologic mechanism responsible for anetoderma is not yet entirely clear. There may be multiple mechanisms. In SLE and APLS, the elastic fibers of the skin may be the targets of an autoimmune process. In other cases, anetoderma may be due to impaired production of elastin by an infectious agent, a drug (such as penicillamine), prematurity, or a genetic mutation.
Anetoderma comes from the Greek anetos, slack or relaxed + derma, skin. Anetoderma has been called by a number of other names, including atrophia cutis, atrophia maculosa, atrophoderma maculatum, and macular atrophy.
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