Machado, SPires, CManji, H2015-08-172015-08-172013Sinapse. 2013 Maio;13(1):15-221645-281Xhttp://hdl.handle.net/10400.10/1489Neuromuscular junction disorders are a heterogeneous group most often caused by imune or genetic abnormalities. They comprise Myasthenia Gravis, Lambert-Eaton Syndrome and Congenital Myasthenic Syndromes. Despite affecting different parts of the synapse, they share clinical and neurophysiological features, posing a diagnostic challenge. These disorders can be divided in subgroups, according to the causing antibody or genetic defect. However, there are no established clinical criteria and the accurate diagnosis is highly dependent on the recognition of phenotypes. The identification of clues both in the history and examination may be precious to the correct diagnosis. Treatment depends on the underlying abnormality and the prognosis is generally good. However, more severe forms of Myasthenia Gravis and paraneoplastic: Lambert-Eatom Myasthenic Syndrome are recognized.engCongenital myasthenic syndromesMyasthenia gravisDifferential diagnosisSíndromes miasténicos congénitosMiastenia gravisDiagnóstico diferencialjournal article