Bathing trunk nevus

Injury	Disease	Nutrition	Poison

Symptoms	Surgery	Test	Special Topic

Congenital nevus on the abdomen

Bathing trunk nevus

Definition:

A bathing trunk nevus is a darkly pigmented, disfiguring, often hairy patch of skin (nevus) present at birth, which may cover an extremely large area of the body. Sometimes the nevus covers most of the trunk, the upper arms, and thighs.

Alternative Names:
Congenital giant pigmented nevus; Giant hairy nevus
Causes, incidence, and risk factors:

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Bathing trunk nevi are thought to be caused by spontaneous mutations or other events during fetal development, but in some families, the frequent appearance of these lesions suggests that they may be genetically inherited. They may be associated with other birth defects.

The surface texture may vary from smooth to warty, and the color varies from brown to bluish black. Bathing trunk nevi may cause emotional problems because of their appearance.

They can also be dangerous. The nevus has a high risk of developing into melanoma (a type of skin cancer). The risk is thought to be between 3% and 7%.