Familial nonmembranous aplasia cutis of the scalp.

Aplasia cutis of the scalp is often a sporadic condition, but familial occurrences with an autosomal dominant inheritance have been documented. Aplasia cutis of the scalp may be seen in two main clinical variants: oval-shaped membranous aplasia cutis and irregular, larger defects. We report six families in whom more than one member has aplasia cutis of the scalp, all of them with large irregular defects located over the vertex or anterior to the vertex along the sagittal suture. We review previous reports of this entity with clinical pictures and note that in most instances, the defects are of the nonmembranous variant.