Myopathies in the adult patient

About 70,000 people in the UK (around 62 million) have a peripheral neuromuscular disorder, with about one-half of them having a myopathy. They can be acquired or inherited. Most of the former respond to removal of the cause or specific treatment, whereas most of the latter have no specific treatment. Much can be done to improve quality of life and reduce morbidity and mortality in hereditary myopathies, particularly relating to cardiac and respiratory management. Precise molecular diagnosis is essential for accurate genetic counselling and the provision of reproductive options. All of these diseases are best managed by a multidisciplinary team led by a specialist clinician. Many individual myopathies are extremely rare, and the generalist cannot be expected to identify all of them. However, generalists should have the generic skills to be able to recognize the broad nature of the problem and to refer on as appropriate. It is indefensible to miss a treatable disorder such as myositis or drug-induced myopathy, and the generalist should be aware of the major clinical features and management issues of the more common disorders, notably myotonic dystrophy and those with multisystemic manifestations, such as the mitochondrial cytopathies.