Spinal Muscular Atrophy (SMA)

Early Signs and Symptoms of Spinal Muscular Atrophy

Generally, the later a person starts developing symptoms, the milder the disabilities will be. This is because later-onset forms of SMA, such as SMA type 2 or type 3, allow the muscles to develop at least partially while the body can still produce some of the SMN protein. For children with these types of SMA, the first symptoms might include early muscle fatigue, falling, loss of balance and difficulty performing tasks that used to be easy.

Infants born with SMA type 1 often start showing symptoms shortly after birth because they have little or no chance to produce the SMN proteins needed for healthy muscle functioning. Low muscle tone (“floppy baby”), with poor head control and limited leg movement are the main features of SMA type 1. Some babies have a quivering tongue, a telltale sign that alerts doctors that the infant may have SMA. Others might have difficulty sucking or have a belly-breathing pattern or fail to reach common development milestones such as sitting up or rolling over. 

No matter which type of SMA is involved, the sooner the condition can be diagnosed, the earlier the child can start receiving medications and therapy to optimize the child’s function and well-being.

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