Juvenile myasthenia gravis is the most common of the three types of myasthenia gravis seen in children and adolescents. The other two are the congenital and transient neonatal forms.

Juvenile MG, which usually begins before age 18, is a rare, chronic condition that requires life-long management. Its symptoms — muscular weakness and fatigue — are treatable. And children with the condition — especially those who develop the disease before puberty — may have long stretches without relapses. It is crucial to their wellbeing for them to have a well-balanced rest and play scheme as well as age-appropriate independence.

By following a proper treatment regimen and having frequent consultations with medical professionals, most juvenile myasthenia gravis patients can lead normal, productive lives.

What causes juvenile myasthenia gravis?

Like myasthenia gravis in adults, the juvenile form is an autoimmune disease. The hallmark of such diseases is that the immune system-generated antibodies that normally fight off bacteria and viruses mistakenly attack the body’s own tissue. In the case of myasthernia gravis, the antibodies attack the connection between nerves and muscles. This leads to weakness in voluntary muscle movements, mainly in the eyes, mouth, throat, and limbs.

Scientists don’t know why immune cells attack nerve-muscle connections. Some patients have a bigger than normal thymus, the gland that produces immune T-cells. This has led to scientists thinking the thymus is responsible for the malfunctioning of some myasthenia gravis patients’ immune systems.

Juvenile myasthenia gravis is more common in white teenage girls than in boys. About 10 percent of all myasthenia gravis cases start when a person is a juvenile. It is also more common in Asians than others.

Symptoms of juvenile myasthenia gravis

The most typical symptoms of juvenile myasthenia gravis are similar to those seen in adults.  They include drooping eyelids, double vision, tiring easily, and having difficulty eating and swallowing. Some children experience shortness of breath, speech impairment, or changes in facial expression.

When myasthenia gravis starts before a child reaches puberty, it can be limited to muscles of the eyes and eyelids. When it strikes youngsters who have reached puberty, it often involves more generalized weakness.

Patients usually show milder symptoms early in the day, with symptoms worsening toward the end of the day as their fatigue builds.

Diagnosing juvenile myasthenia gravis

Juvenile myasthenia gravis symptoms can start gradually and may be difficult to recognize at first. Because it is a rare disease, and its symptoms are shared with a number of other illnesses, it may take time for doctors to make a diagnosis.

Among the tests used to diagnose it are blood tests that can confirm the presence of antibodies that attack nerve-muscle connections. A catch is that young children typically lack the antibodies, whether or not they have juvenile myasthenia gravis.

Doctors are also likely to perform an electromyography nerve conduction study to measure communication between nerves and muscles. The test focuses on the electrical signals the body uses to communicate.

A tensilon test involves administering edrophonium through infection or IV infusion. Edrophonium prevents antibodies from destroying the neurotransmitter acetylcholine, temporarily relieving muscular weakness. If the treatment leads to a quick improvement in a person’s muscle strength, it’s an indication they may have myasthenia gravis.

Treating juvenile myasthenia gravis

Juvenile myasthenia gravis can be treated with acetylcholinesterase inhibitors, corticosteroids, plasmapheresis, or intravenous immunoglobulin (IVIg). The inhibitors are often the preferred choice.

Adult myasthenia gravis patients often develop a condition known as thymoma, or a benign tumor in the thymus. Surgical removal of the thymus can be an effective treatment. Although thymoma is not common among children, some juvenile myasthenia gravis patients may benefit from the gland’s removal.

Children with myasthenia gravis who have serious swallowing problems may need to be tube-fed to receive enough nutrients.  Likewise, those with breathing difficulties may need respiratory support.

***

Myasthenia Gravis News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.