Congenital Myopathies

What is Congenital Myopathies?

Congenital myopathies is a term that describes various diseases that affect the muscles. These disorders are hereditary, which means that either both parents or one parent is a carrier and the disorders are the result of defects in numerous genes. This type of disorder most always exists at birth but it can appear in young children.

The disorders that fit into the category of congenital myopathies are central core disease, nemaline rod myopathy, congenital fiber type disproportion and myotubular myopathy. Diagnosing these disorders consist of blood tests, muscle biopsies, genetic testing and electrodiagnostics.

What are the Symptoms of Congenital Myopathies?

Central core myopathy symptoms can be mild or extensive and they vary from one person to another.

Symptoms include

Weak muscles, reduced muscle tone and breathing problems. Facial muscles are often affected in individuals who have nemaline myopathy and this gives the face a lengthened appearance.

Speaking can be challenging and some individuals have trouble swallowing. Myotubular myopathy symptoms may include eyelids that droop, fingers and toes that are exceptionally long, a larger-sized head and problems focusing on objects that are distant. Symptoms of congenital fiber type disproportion myopathy include weakened muscles in the trunk, face, neck and limbs. Respiratory failure is possible in infants who have this disorder.

Congenital Myopathy Causes

Congenital myopathy is a catch all term applied to rare neuromuscular diseases that are present at birth. Because these diseases are different, they have different causes. Despite this, almost all congenital myopathies are caused by genetic mutations or rare genetic inheritance disorders. Several different genes can be affected depending on the myopathy present. Most of the diseases seem to be linked to dominant genes that result from mutations and are passed onto children. Myopathies can also arise from sex linked genes and from recessive genes; these are thought to be stronger forms and those afflicted with the disease – if it is X linked or recessive – tend to have grimmer prognoses. All of the genes affected have been identified as genes related to malfunctions in muscle development, with the more common myopathies affecting development of various muscle proteins or protein receptors.

How is an Congenital Myopathies Treated?

Since there is no cure for congenital myopathies, medical professionals offer treatments that can reduce the severity of the symptoms.

Treatment includes

Popular medications to lessen negative effects of this condition include anticonvulsants, such as quinine and phenytoin. Physical therapy sessions for rehabilitating the weakened muscles is a priority. Individuals can perform daily stretching activities and exercises to help make their muscles stronger. It is recommended that parents who have a child that is diagnosed with congenital myopathies seek genetic counseling from a professional.

Congenital Myopathy Prevention

It is unknown what causes the genetic mutations that result in children developing congenital myopathies. The best method for prevention is to see a genetic counselor and understand the family history of both parents. If a congenital myopathy is present in a family member, there is a chance that it may also be present in a child depending on the nature of the myopathy. A parent having a congenital myopathy would greatly increase the chance of their child also having the same congenital myopathy.

Monitoring of a fetus during its time in the womb and directly after can indicate whether or not a congenital myopathy might be present. Genetic mutations that might cause myopathies can be caused by external environmental factors such as harsh infections, drug and alcohol abuse, and certain medications, such as some medications associated with the lowering of cholesterol. The best preventative measure in this case is to live a healthy lifestyle free of drug and alcohol abuse, and to be aware of the potential dangers of medication being taken during pregnancy.

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Last Reviewed:
September 19, 2016
Last Updated:
December 08, 2017