Most patients have other symptoms as well, in which case they have generalized myasthenia gravis.
Congenital MG is believed to have an inherited genetic basis. There are a few similar disorders that may be mistaken for MG, or that have like features. These bacteria can block the receptor for Ach at the muscle membrane, resulting in muscular weakness. Treatment is with antitoxin. This disorder is associated with malignancies, particularly specific types of lung cancer.