Neuromyotonia

Neuromyotonia which is a neurological disease, which is characterized by an increased sensitivity of skeletal muscle, and is described as an autoimmune disease or paraneoplastic syndrome in small cell lung cancer, lymphomas, and thymomas. Cause is a faulty function of the neuromuscular junction ( motor end plate ), which causes the vast majority of cases by the formation of autoantibodies against voltage-gated potassium channels ( Isaac - Mertens syndrome) is. If the neuromyotonia occurs in conjunction with symptoms of limbic encephalitis, Morvan 's syndrome is the term used. In addition to the acquired there are also inherited forms. The neuromyotonia has been described in the 60s by Hyam Isaacs and Hans- Georg Mertens.

Clinic

The neuromyotonia occurs sporadically and at any age, it is considered very rare. Dominate clinically involuntary tonic muscle cramps, fasciculations and particularly characteristic feature durable, wave-like muscle contractions, which are clearly visible in lean persons ( Myokymien ). Often, the muscles can not be really relaxed and appears stiff ( Pseudomyotonia ). Sometimes, moreover, their excessive sweating ( hyperhidrosis ). Electromyography muscle action potentials can be detected in relaxation. In approximately 40% of patients, antibodies against voltage-gated potassium channels in the serum can be detected, many sufferers also have other autoantibodies, for example against acetylcholine receptors as in the myasthenia gravis.

Treatment is symptomatic, with antiepileptic drugs ( phenytoin, carbamazepine, valproic acid, lamotrigine ), immunosuppression or plasmapheresis. The removal of the tumor, if present, the symptoms often will not improve significantly.