In assessing a newborn with a head swelling that crosses suture lines, which condition is indicated?

The condition associated with head swelling in a newborn that crosses suture lines is caput succedaneum. This condition arises during delivery, particularly with prolonged labor or when using vacuum extraction. It is characterized by the accumulation of serosanguineous fluid in the soft tissues of the scalp, resulting in a swelling that is usually evident at birth.

Caput succedaneum differs from cephalohematoma, which is a collection of blood that occurs beneath the periosteum of the skull and does not cross suture lines due to the confined nature of the space under the periosteum. Nevus flammeus and erythema toxicum are unrelated conditions that do not present with the same type of head swelling as caput succedaneum and are typically identifiable by other means, such as their characteristic appearance on the skin rather than the swelling associated with labor and delivery.