Paraneoplastic or autoimmune neuromuscular transmission disorders
Definition
NMT disorders are defined by a variable disturbance of the function of the neuromuscular transmission, resulting in fluctuating muscle weakness and fatigue. These are usually classified into pre- and postsynaptic disorders. Presynaptic disorders, mainly the Lambert Eaton Myasthenic Syndrome (LEMS) is associated with antibodies targeting the voltage gated calcium channels (PQ and N type). LEMS is associated with malignancy (pulmonary or extra-pulmonary small cell carcinoma) in about 50% of cases. In the context of LEMS the detection of SOX 1 (anti glial nuclear) antibodies is highly predictive of cancer. Postsynaptically, myasthenia gravis is mostly (> 90%) associated with antibodies targeting the muscle acetylcholine receptor (AChR) or rarely other proteins (including muscle -specific kinase -MuSK). Myasthenia is usually not considered a paraneoplastic disease, with the exception of thymoma in about 10% cases.
Also indexed as
Nearby in Paraneoplastic or autoimmune disorders of the nervous system
8E4A.0Paraneoplastic or autoimmune disorders of the central nervous system, brain or spinal cord8E4A.1Paraneoplastic or autoimmune disorders of the peripheral or autonomic nervous system8E4A.3Paraneoplastic or autoimmune disorders of the muscle4B4YOther specified diseases of the immune system4B4ZDiseases of the immune system, unspecified