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Lambert-Eaton Myasthenic Syndrome (LEMS)

Lambert-Eaton Myasthenic Syndrome (LEMS)

It is a rare, autoimmune disease of unknown frequency, in which there is a presynaptic disorder in the transmission of the neuromuscular signal. It refers to older people and more often to men.


Symptoms - mostly muscle weakness - are milder than those of Myasthenia Gravis. It slowly evolves and attacks the muscles close the torso (mainly the pelvis, thighs, shoulders and the upper part of arms). This causes walking problems, raising the ladder, lifting up from sitting upright. It has been found that weakness deteriorates in high temperature exposure.

Secondary, mucosal and ocular muscles are mildly affected, creating diplopia, dysarthria, bleeding, much milder than the corresponding Gravis symptoms. In addition, reduced tendon reflexes, autonomic nervous system disorders (such as decreased sweating and constipation) are observed, while the respiratory system is rarely affected. In 50-70% of patients there is cancer, mainly in the lungs, malignant thymomas, lymphosarcomas, chest, stomach, bladder, kidney, gall bladder cancers.



  • Clinical examination,
  • Electromyography,
  • Immunological tests,
  • Detection of coexisting carcinomas.



There is no cure. Only the symptoms are treated, but they vary depending on age, general physical condition and the presence or absence of cancer. If cancer coexists, is treated first and by convention, then the symptoms of myasthenia are relieved. In addition, immunosuppressive drugs, such as prednisone, alone or in combination with azathioprine or cyclosporin, are administered to suppress the autoantibodies causing the disease.

For follow-up clinical trials on the disease visit:







Muscular Dystrophy Association