Werdnig-Hoffman disease (also known as "Infantile spinal muscular atrophy", "spinal muscular atrophy type 1", or "spinal muscular atrophy type I")) is an autosomal recessive muscular disease and is the most severe form of spinal muscular atrophy. It is evident before birth or within the first few months of life. There may be a reduction in fetal movement in the final months of pregnancy. The condition tends to deteriorate over time, depending on the severity of the symptoms. Affected children never sit or stand and usually die before the age of 2, if not provided breathing support. However, some individuals have survived to become adults.
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