It is a life-long condition that may go in and out of remission. About 20 percent of MG cases are juvenile-onset. The following are the most common symptoms of myasthenia gravis. However, each child may experience symptoms differently. A few babies may need the help of a mechanical breathing machine if their respiratory muscles are too weak to breathe on their own.
Symptoms go away as the maternal antibodies disappear over time.
Congenital MG symptoms may begin in the first year, with generalized weakness in the arms and legs, and delays in motor skills such as crawling, sitting, and walking. Babies may have difficulty feeding and may have weak eyelids and poor head control. Juvenile MG symptoms may begin gradually over weeks or months. The child may become excessively tired after very little activity, and begin to have problems chewing and swallowing. Drooping eyelids may be so severe that the child cannot see.