Seronegative nonparaneoplastic Lambert—Eaton myasthenic syndrome

Abstract

The authors studied two patients with Lambert-Eaton myasthenic syndrome (LEMS) in whom the repeated examination did not find specific of LEMS P/Q type voltage-gates calcium channel autoantibodies. The results of clinical testing and electrophysiological examination showed the typical character of movement disorders with the absence of tendon reflexes and signs of disautonomia as well as a decrease in M-response amplitude and phenomena of decrement with low frequency- and increment with high frequency stimulation. Both patients revealed no signs of paraneoplastic process. Autoimmune character of the damage was confirmed by the effectiveness of treatment with glucocorticoid hormones.