Spinal muscular atrophy (SMA) is a rare genetic disease. SMA patients are missing the SMN1 gene, which encodes SMN, a protein necessary for motor neuron functioning. In patients with SMA, motor neurons in the spinal cord gradually die, leading to neuronal connections to muscles dying off and muscle atrophy - the complete cessation of muscle activity over time. It is a gradual but irreversible process, meaning the loss of the ability to move, and eventually, to breathe.
SMA is the most common genetic cause of death in children. Without treatment, children with type 1 SMA only live up to two years. The effectiveness of therapy and rehabilitation depends on how early to complete diagnostic and start treatment since destroyed motor neurons are unrecoverable.
There are four types of SMA, which differ depending on the age of manifestation (first symptoms) and the degree of symptoms manifestation.
- Type 1 SMA occurs in infants during the first months of life, from birth to 6 months of life. It is the most severe form of the disease. Without treatment, children with this disease type usually do not survive until they are two years old.
- Type 2 SMA is seen in children from age 6 months to 18 months. Children with this type of disease can sit up without support but are unable to stand up and walk. The severity of the course and prognosis, in this case, depends on whether respiratory problems are part of the symptoms.
- СМА Type 3 SMA first appears after a child's first 18 months of life. Children suffering from this disease type can walk on their own for a while because weakness and muscle atrophy progress slowly.
- SMA type 4 is the adult form. Symptoms are seen in adolescents at the age of 20 and slowly progress. Typically, this form of disease does not decrease a person's life expectancy.
People with SMA require urgent treatment and rehabilitation regardless of their age or form of the disease.
For those who wish to gain a deeper understanding of SMA, we recommend the following resources: