In 1859, Landry described an acute disease of the nervous system of which the chief symptom was an ascending paralysis of rapid development that ended, as a rule, in death from asphyxia. The motor paralysis was of lower motor neuron type with loss of tendon reflexes. Sensory changes were minimal or absent. The sphincters were usually not disturbed. No gross or microscopic alterations of the nervous system could be demonstrated by the methods of study available at the time.
For many years there was a tendency to force into this group every instance of acute ascending paralysis, and as a result classification became much confused. This tendency was especially apparent in the reports of purely clinical studies on patients whose nervous systems had not been adequately examined after death. As larger series of case reports became available for study, it seemed probable that acute ascending paralysis, with more or less