Linear Nevus Sebaceous Syndrome (LNSS)
LNSS is a rare condition in which a nevus sebaceous occurs along with problems in other organ systems. A nevus sebaceous is a hairless patch of skin that is present at birth. It is most often found on the scalp, face, or neck. Most people with a nevus sebaceous have no other problems. Rarely, a person with a nevus sebaceous will have other issues such as:
- intellectual disability.
- eye problems.
- bone problems.
- enlargement of one side of the brain.
- heart defects.
- greater risk of cancer.
Everyone with LNSS has at least one nevus. A person with a large nevus is more likely to have other problems than someone with a small one. The most common other problems are seizures and intellectual disability. Up to two-thirds of people with LNSS have seizures, but not everyone does. Such seizures most often start during the first year of life. People with LNSS may have normal intelligence, but most have some level of intellectual disability.
Although the nevus is present at birth, other symptoms of LNSS can start at different times. People with LNSS may have two or three or more of the other symptoms. If a child with a nevus sebaceous begins to show one of the other signs of LNSS, he or she should be checked for more. Exams should focus on the skin, eyes, brain, skeleton, and heart. Your child may need a team with more than one specialist. A neurologist is usually part of this team, and may recommend a brain scan such as a CT or MRI, and an EEG.
The nevus grows at the same rate as the child. As the child enters puberty, it may become thick, raised, and warty. A nevus sebaceous may become cancerous later in life. Your doctor may suggest surgery to remove the nevus.
The outlook for a person with LNSS depends on how many other problems are involved. It also depends on how serious those other issues are. Specialists can help decide how to follow and treat each of the problems.
Doctors are not sure of the causes of LNSS. It is not inherited (passed down from parent to child.) It may be caused by a random gene mutation during the early weeks of a pregnancy. LNSS is found in both males and females of all races. It is not caused by anything the mother did while she was pregnant.
For More Information
From the Genetic and Rare DiseasesHealthInformationCenter
Linear Nevus Sebaceous Syndrome
Online LNSS Support Group
LNSS-Connections on Yahoo! Groups
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 04/29/2010
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