Myasthenia gravis with clinical facilitation: a case series

Abstract

Patients having features of both myasthenia gravis (MG) and Lambert-Eaton myasthenic syndrome (LEMS) have been reported and have been collected under the term MG-LEMS overlap syndrome (MLOS). These patients have clinical characteristics of MG and LEMS, but electrophysiological features of presynaptic pathology. Three patients who were initially diagnosed as LEMS because of presentation with predominant extremity weakness which showed clinical facilitation (transient increase in muscle strength on repeated muscle strength examination) were reported in this case series. All three patients were finally diagnosed as anti-acetylcholine receptor positive MG. None of them had voltage gated calcium channel antibodies. Electrophysiological features were compatible with LEMS in one patient who was considered to have MLOS. The other two patients had electrophysiological features of MG. Patients showing features of both disorders were reported previously, but to our knowledge no patient with MG showing clinical facilitation was reported. It would be interesting to check MG patients with predominant extremity weakness for clinical and electrophysiological features of LEMS.