Spinal muscular atrophy is a genetic or inherited disease affecting muscles and nerves. This neuromuscular condition leads to the weakening of body muscles. Research indicates that nearly 10,000 to 25,000 children and adults in the country live with this condition. Individuals with this disorder are prone to frequent respiratory infections and sometimes pneumonia. Below you can learn about the types of spinal muscular atrophy, their symptoms, and treatment options to manage the condition.

Types

Spinal muscular atrophy mainly affects infants and children, and due to this disease, they cannot use their muscles effectively. Such an issue causes the breakdown of the nerve cells in the spinal cord and brain. So, in this condition, the muscles cannot receive the nerve signals that help with muscle movement. The term atrophy implies that specific muscles become weak and small with this disease. A person suffering from spinal muscular atrophy inherits two copies of the mutated SMN1 (Survival Motor Neuron1) gene. One mutated gene from the father and the other one from the mother.

Spinal muscular atrophy can be divided into four main types:

Type 1
This type is commonly referred to as severe SMA, also known as the Werdnig–Hoffmann disease. The symptoms usually appear at the time of birth or during the first six months of the infant’s life. Infants with SMA type 1 cannot suck or swallow or hold up their heads or sit. Children with SMA type 1 have collapsed lungs and are prone to respiratory infections.

Type 2
Type 2 or Intermediate SMA is also known as Dubowitz disease. The symptoms usually appear when the child is between six and eighteen months of age. The lower limbs are affected by this type of spinal muscular atrophy, and the child can sit but cannot walk.

Type 3
Type 3 or Mild SMA is also known as Juvenile onset SMA or Kugelberg-Welander SMA. It occurs after eighteen months from birth. Type 3 leads to mild muscle weakness, frequent respiratory infections, and walking difficulties. In the future, there may be difficulty walking or standing.

Type 4
This rare condition does not occur until the mid-30s. The muscle weakness symptoms develop slowly, and other symptoms may be twitching or breathing problems.

Symptoms and complications

As discussed, the symptoms of spinal muscular atrophy may vary depending on the type. Generally, individuals with this condition may lose muscle strength, control, and movement. Symptoms such as muscle loss may get worsen with age. Some people gradually lose the ability to sit, stand, or walk. Possible complications that may develop due to spinal muscular atrophy are

• Respiratory infections
• Pneumonia
• Problems with swallowing
• Spine curvature, i.e., scoliosis
• Bone fractures
• Hip dislocation
• Weaker lungs

There is a need to call the doctor when a person with spinal muscular atrophy experiences these symptoms:

• Difficulty breathing
• Cough
• Fever
• Nausea
• Vomiting
• Diarrhea
• Extreme fatigue
• Dehydration

Diagnosis

Healthcare providers conduct a physical exam to learn about the patient’s medical history. The following tests may be conducted to diagnose spinal muscular atrophy:

Blood test
A protein and enzyme blood test is conducted to check the creatine kinase levels, an enzyme released into the bloodstream by the deteriorating muscles.

Genetic test
This test determines if the condition is caused due to the altered SMN1 gene. It has been found that it is 95% efficient and effective.

Nerve conduction test
An electromyogram measures the electrical activity of the nerves and the muscles.

Muscle biopsy
Such a test is used to depict atrophy or muscle loss. Tiny muscle tissue is taken out and sent to a lab for examination.

Treatment and support

The treatment for spinal muscular atrophy depends upon the type and the prevailing signs and symptoms. Many people with SMA usually benefit from occupational and physical therapy and assistive devices such as crutches, orthopedic braces, wheelchairs, and walkers. Disease-modifying and gene replacement therapies may also help. The following organizations offer support for those with spinal muscular atrophy:

SMA Foundation
It tries to enhance the search for treatment for this disease by working with researchers. It helps to develop clinical trials and educate others about this genetic or inherited condition.

Muscular Dystrophy Association
This group offers details, information, and links to support and service groups in a particular area.

Cure SMA
This foundation helps and funds research to treat, manage, and cure SMA. It also helps people who are newly diagnosed by providing them with the information and support they need.

This neuromuscular disease will affect the quality of life of the patient, and it is a long-term disease that worsens with time. Symptoms may vary as per the type, with SMA type 1 being severe. Therefore, it is essential to consult a health care professional to better manage the symptoms and the disease.