The authors report two cases of infantile spinal muscular atrophy with atypical evolution diagnosed by means of EMG findings. The first one is a 10 years-old female child who has showed a distal predominium of the muscle weakness and atrophy. The second patient, a 7 year-old female child, has manifested within a period of 4 months a rapidly progressive tetraparesis that culminated in death after 10 months. The authors present the most accepted classifications of the illness land discuss the clinical manifestations of the two patients aiming to characterize the clinical forms, in accordance to the literature.
infantile spinal muscular atrophy; clinical variants; atypical forms