A close look at autoimmune muscle disorders: association of Lambert-Eaton myasthenic syndrome with dermatomyositis

Dermatomyositis/polymyositis (DM/PM) and Lambert-Eaton myasthenic syndrome (LEMS) are two autoimmune disorders that have very rarely been reported to occur together in the same patient. We report on two patients with DM who were later diagnosed with concomitant LEMS, and point out diagnostic challenges in identifying LEMS in patients with DM/PM. As specific treatment for LEMS is available, it is important to identify those DM/PM patients who suffer from concomitant LEMS.