Mimic syndromes in sporadic cases of progressive spinal muscular atrophy

Visser J, van den Berg-Vos RM, Franssen H et al. Neurology 2002; 58:1593-1596.
This is a progressive disease of lower motor neurons, aka progressive muscular atrophy, progressive spinal muscular atrophy, and others. Often patients develop UMN signs and qualify for a diagnosis of ALS and these patients are often considered part of the ALS spectrum. The study in the Netherlands was of 89 patients, 17 of whom had other diagnoses in the end. Patients were specifically excluded if they had objective sensory signs, history of diseases that could mimic PMA (spinal radiculopathy, poliomyelitis, diabetic amyotrophy), familyhistoryof SMA, or upper motor neuron signs. 7 patients ultimately met criteria for MMN, 2 with CIDP, 1 limb-gircle dystrophy, 1 inflammatory myopathy, others idiopathic chronic neuropathy, brachial plexopathy, syringomyelia and myopathy. One patient a HNP that recovered, and one had slowly progressive ALS.