Abstract
Abnormalities of neuromuscular transmission were detected in patients with thyroid disease, generalized muscle weakness and easy fatigability. Electromyography (EMG) revealed abnormal fall-off of muscle action potentials evoked by nerve stimulation in 3 patients with myxedema. The clinical picture and positive response to anti-cholinesterase medication in 2 of these cases was consistent with myasthenia gravis. The reverse abnormality, paradoxical potentiation, occurred during thyrotoxicosis in a 4th patient. All the abnormalities cleared with appropriate thyroid treatment. This spectrum of neuromuscular synaptic abnormality in thyroid disease might be caused by an effect of thyroid hormone on the synapse.

This publication has 1 reference indexed in Scilit: