Unilateral progressive muscular atrophy with fast symptoms progression.

Progressive muscular atrophy (PMA), or the lower motor neuron disease, is a sporadic disorder characterized by onset in adulthood, pure lower motor neuron involvement and relatively benign course. Muscle atrophy and weakness may be symmetrical or asymmetrical, but they are always bilateral. We present a male patient with exclusively left-side flaccid paresis due to lower motor neuron disease without electromyographic evidence of neurogenic lesion of contralateral muscles and with no signs of corticospinal tracts involvement. The rapid disease progression was typical of the generalized phenotype of PMA and it suggested the relation to the aggressive course of classical ALS.