Nemaline Myopathy is a non-progressive neuromuscular disease that affects muscle strength and development. This condition is one of the 40 diseases currently covered by the MDA (Muscular Dystrophy Association). There are six forms of the condition, as described by the National Institutes of Health. The six forms include:
- Severe Congenital
- Amish NM
- Intermediate Congenital
- Typical Congenital
- Childhood-Onset
- Adult-Onset
There is overlap between the forms of Nemaline Myopathy, which means one person can suffer from more than one form simultaneously.
Who is at Risk?
About 50-percent of Nemaline Myopathy cases are associated with inheritance from parents with dominant or recessive forms of the disease. The remaining 50-percent of cases are characterized as first in family, which means no genetic history of the condition exists.
Symptoms
Nemaline Myopathy is a disease that affects muscle development. Typically, symptoms include:
- Muscle weakness
- Altered deep tendon reflexes
- Gastroesophageal reflux
- Scoliosis
- Joint contractures
- Decreased respiratory function
Diagnosis
Nemaline Myopathy is rare and many of the symptoms overlap other disease and condition symptoms, so family history and accurate and detailed symptom reporting is extremely important for an accurate diagnosis. Doctors look for muscle weakness, often most severe in facial muscles and deep tendon response delay. If symptoms appear to be associated with Nemaline Myopathy, medical testing can be used to confirm the diagnosis. Some of the medical tests associated with the condition include:
- Electromyopathy
- Nerve conductive tests
- Ultrasound
- CT scan
- MRI scan
- Blood tests
Treatment
Treatments for Nemaline Myopathy focus on symptoms. There is no known cure for the condition. Patients are often treated for respiratory issues and gastrointestinal issues with medication. Altering the diet to improve nutritional status and decrease the risk of gastrointestinal symptoms.
Patients may also undergo physical therapy for increased muscle strength and mobility. If the condition presents in infancy, outcome is often determined by muscular development and walking. If the patient is walking by 18-months, the rate of survival improves.
Life Expectancy
There are six forms of Nemaline Myopathy and the survival rate for each condition and the resulting overlapping conditions differ. Patients with the most severe form of the condition may experience significant symptoms that may lead to reduced life span. Milder forms of the disease tend to affect the patient’s daily life, but don’t affect life span with proper treatment.
One of the main causes of death in patients with Nemaline Myopathy is respiratory distress. Patients may require breathing aids, particularly at night, to reduce respiratory symptoms and increase life span.