Congenital myasthenic syndrome: report of four cases and brief review of literature.

The term 'congenital myasthenic syndrome' (CMS) encompasses a number of heterogeneous disorders characterised by myasthenic symptoms since birth, usually with positive family history and absence of acetyl choline receptor antibodies. Recent advances in electrophysiology and ultrastructural analysis of neuromuscular junction have made it possible to identify the various defects underlying these disorders. We report four cases of CMS, with a review of literature.