Pharmacologic concerns of corticosteroids in the treatment of patients with immune-related neuromuscular diseases.

Traditionally, diseases affecting the motor unit had been subdivided based on anatomic criteria into diseases of the anterior horn cell, the peripheral nerve, the neuromuscular junction, and the muscle itself. For therapeutic considerations, however, a more precise cellular and clinicopathologic characterization of the diseases affecting the motor unit is needed. Based on the site and cell of the primary pathologic change, this article presents an immunotherapy-oriented broad classification of neuromuscular diseases affecting the motor unit.