Spinal muscular atrophy (SMA) is a rare genetic disease that weakens muscles, making even basic activities like walking or breathing challenging. But for those living with SMA, the true strength lies within. They are warriors fighting a daily battle, defying limitations, and inspiring us all with their unwavering spirit.
We’ll delve into the science behind the disease as we share the story of Karen (not real name). Karen is a 22 year old who was diagnosed with SMA when she was a teenager. Join us on this journey of understanding SMA.
What is spinal muscular atrophy (SMA)?
Spinal muscular atrophy (SMA) is a genetic inherited neuromuscular disease that causes muscles to become weak and waste away. People with SMA lose a specific type of nerve cell in the spinal cord called motor neurons, that control muscle movement. Without these motor neurons, muscles don’t receive nerve signals that make muscles move. With SMA, certain muscles become smaller and weaker due to lack of use.
What are the types of spinal muscular atrophy?
There are four primary types of SMA:
- Type 1 (severe): About 60% of people with SMA have type 1. It is also called Werdnig-Hoffman disease. Symptoms appear at birth or within an infant’s first six months of life. Infants with type 1 SMA have difficulty swallowing and sucking. They don’t meet typical milestones like holding up their heads or sitting. As muscles continue to weaken, children become more prone to respiratory infections and collapsed lungs (pneumothorax).
- Type 2 (intermediate): Symptoms of type 2 SMA (also called Dubowitz disease) appear when a child is between six months and 18 months old. This type tends to affect the lower limbs. Children with type 2 SMA may be able to sit up but can’t walk. Most children with type 2 SMA live into adulthood.
- Type 3 (mild): Symptoms of type 3 SMA (also called Kugelbert-Welander or juvenile-onset SMA) appear after a child’s first 18 months of life. Some people with type 3 don’t have signs of disease until early adulthood. Type 3 symptoms include mild muscle weakness, difficulty walking and frequent respiratory infections. Over time, symptoms can affect the ability to walk or stand. Type 3 SMA doesn’t significantly shorten life expectancy.
- Type 4 (adult): The rare adult form of SMA doesn’t typically appear until the mid-30s. Muscle weakness symptoms progress slowly, so most people with type 4 remain mobile and live full lives.
What are the symptoms of spinal muscular atrophy?
SMA symptoms vary depending on the type. In general, people with SMA experience a progressive loss of muscle control, movement and strength. Muscle loss gets worse with age. The disease tends to severely affect the muscles closest to the torso and neck. Some people with SMA never walk, sit or stand. Others gradually lose their ability to do these actions over time.
How is spinal muscular atrophy diagnosed?
SMA can be diagnosed through a range of tests which include:
- Blood test: An enzyme and protein blood test can check for high levels of creatine kinase. Deteriorating muscles release this enzyme into the bloodstream.
- Genetic test: This blood test identifies problems with the SMN1 gene. As a diagnostic tool, a genetic test is 95% effective at finding the altered SMN1 gene.
- Nerve conduction test: An electromyogram (ECG) measures the electrical activity of nerves muscles and nerves.
- Muscle biopsy: A physician may perform a muscle biopsy. This procedure involves removing a small amount of muscle tissue and sending it to a lab for examination. A biopsy can show atrophy, or loss of muscle.
Can spinal muscular atrophy be treated?
There is no cure for SMA. Treatments given by physicians are usually to manage the condition and medication given depends on the type of SMA and symptoms. Many people with SMA benefit from physical and occupational therapy and assistive devices, such as crutches, walkers and wheelchairs. Other treatments usually administered include these treatments may also help include disease-modifying therapy and gene replacement therapy.
Conclusion
Living with SMA is a testament to the power of hope, determination, and the unwavering support of loved ones. Remember, even the smallest act of awareness or kindness can have a ripple effect, creating a brighter future for those living with this condition. Let their stories inspire you to make a difference.