Type I spinal muscular atrophy can mimic sensory-motor axonal neuropathy.
Spinal muscular atrophy is a group of allelic autosomal recessive disorders characterized by progressive motoneuron loss, symmetric weakness, and skeletal muscle atrophy. It is traditionally considered a pure lower motoneuron disorder, for which a current definitive diagnosis is now possible by molecular genetic testing. We report two newborns with a clinical phenotype consistent with that of spinal muscular atrophy type I and nerve conduction studies and electromyography suggesting more extensive sensory involvement than classically described with spinal muscular atrophy. Molecular testing confirmed spinal muscular atrophy in patient 1 but not in patient 2. Thus, in the setting of a suspected congenital axonal neuropathy, molecular testing might be necessary to distinguish spinal muscular atrophy type I from infantile polyneuropathy.
Anagnostou
Evdokia
E
Division of Pediatric Neurology, Montreal Children's Hospital, Department of Neurology, McGill University, Montreal, Quebec.
Miller
Steven P
SP
Guiot
Marie-Christine
MC
Karpati
Greoge
G
Simard
Louise
L
Dilenge
Marie-Emmanuelle
ME
Shevell
Michael I
MI
D003937:Diagnosis, Differential; D015417:Hereditary Sensory and Motor Neuropathy / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009431:Neural Conduction / Q000502:physiology; D014897:Spinal Muscular Atrophies of Childhood / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology*; D013127:Spinal Nerves / Q000473:pathology / Q000503:physiopathology