Myasthenia gravis (MG) is a disorder that causes weakness in muscles around the body. This happens because antibodies destroy some of the places where nerves and muscles meet (neuromuscular connections). MG affects the voluntary muscles of the body. It mostly affects the eyes, mouth, throat, arms and legs. It most often affects adults, but it can sometimes happen in children.
There are three types of MG in children:
Transient neonatal MG
This is a temporary form of MG. It can happen in babies born to mothers with MG. It occurs when antibodies from MG cross over to the baby growing in the mother’s uterus. Transient neonatal MG usually lasts only a short time. The symptoms go away weeks or months after birth, as the antibodies are naturally replaced. Babies are not at greater risk of developing MG later in life.
This is an autoimmune disorder. It most often occurs in white teen girls. It is a lifelong condition that may go in and out of remission. Treatment is often done by removing the entire thymus gland. This may cure the disorder.
This is a very rare form of MG. It is not an autoimmune disorder. It is inherited as an autosomal recessive disease. This means that both boys and girls are equally affected. It also means that two copies of the gene, one inherited from each parent, are needed to have the condition. There are about 12 rare genetic disorders that may cause congenital MG. Symptoms of congenital MG usually start at birth and are lifelong. Some forms may be treated with the same medicines that are used for adults.