Congenital myopathy refers to a group of muscle disorders that appear at birth or in infancy. Muscle weakness can occur for many reasons, including a problem with the muscle, a problem with the nerve that stimulates the muscle, or a problem with the brain. Therefore, to diagnose a congenital myopathy, a neurologist will perform a detailed physical exam as well as tests to determine the cause of weakness. If a myopathy is suspected, possible tests include a blood test for a muscle enzyme called creatine kinase, an electromyogram (EMG) to evaluate the electrical activity of the muscle, a muscle biopsy, and genetic testing.
Major research on disease:
No specific treatment is available for any of the congenital myopathies, but aggressive supportive care is essential to preserve muscle activity, to allow for maximal functional ability, and to prolong life expectancy. The primary concerns affecting prognosis are preventing and correcting skeletal abnormalities (eg, scoliosis, foot deformities, contractures) to maintain ambulation, and to prevent or delay the development of respiratory insufficiency. Respiratory failure due to diaphragmatic weakness can occur at any age and may be independent of the degree of limb weakness. A restrictive pattern on pulmonary function tests (PFTs) may be apparent before the onset of symptoms. Early symptoms of nocturnal hypoxia can include poor sleep, nightmares, morning headache, daytime sleepiness, and weight loss. All patients should have baseline PFTs that are repeated in at least yearly intervals. Treatment options include chest physiotherapy, manually assisted cough, early treatment of respiratory infections, noninvasive ventilation, and tracheostomy combined with permanent ventilation.
Congenital myopathies extends to more than 50 diseases today, even excluding the common forms Duchenne Muscular Dystrophy, Myotonic Dystrophy and Facioscapulohumeral Dystrophy. Unfortunately, even by critical clinical evaluation and muscle pathology, diagnosis is still difficult. To potentially remediate this difficulty, we applied a microarray-based targeted next-generation sequencing (NGS) technology to diagnose these patients. There were 55 consecutive unrelated patients who underwent the test, 36 of which (65%) were found to have a causative mutation. Our result shows the accuracy and efficiency of next-generation sequencing in clinical circumstances