Autoimmune Myasthenia Gravis
Autoimmune myasthenia gravis (MG) is a rare autoimmune disorder of the neuromuscular transmission, caused by autoantibodies against targets of the postsynaptic membrane. The cardinal clinical feature is fluctuated muscle weakness of ocular, limb, axial, bulbar and respiratory muscles. About 10-15% of MG cases are paraneoplastic and are associated with thymoma.
Myasthenic crisis
Severe and potentially life threatening involvement of bulbar and /or respiratory muscles, requiring mechanical ventilation. This is the most severe but reversible complication of MG.
Myasthenic Syndrome Lambert-Eaton (LEMS)
Rare autoimmune presynaptic disorder of the neuromuscular transmissio, frequently paraneoplastic in associaton with small cell lung cancer. Proximal weakness of the lower limbs, normal creatine kinase activity, absent tendon reflexes and autonomic dysfunction are highly suggestive of LEMS.
Acquired Neuromyotonia
Rare autoimmune presynaptic disorder of the neuromuscular transmission, about 25% paraneoplastic, resulting in peripheral nerve hyperexcitability symptoms. Autoimmune myasthenia and neuromyotonia are the commonest neurological paraneoplastic manifestations of thymoma.