J Korean Acad Rehabil Med.  2007 Feb;31(1):113-118.

A Case of Type III Proximal Spinal Muscular Atrophy Distinguished from Distal Spinal Muscular Atrophy: A case report

• Kim HS
• Lee SC
• Cho SK
• Park YB
• Lee SH
• Moon JH
• Park YG

Abstract

Spinal muscular atrophy (SMA) is a neuromuscular disorder characterized by progressive anterior horn cell degeneration leading to motor weakness, muscular atrophy and denervation. Recently, the genes responsible for proximal muscular atrophy have been identified and named as survivor motor neuron (SMN) and neuronal apoptosis inhibitory protein genes. The clinical symptoms, courses and evaluation findings of proximal SMA type III are similar to those of distal SMA and proximal muscle myopathies such as limb gir-dle muscular dystrophy and fascioscapulohumeral muscular dystrophy. It cannot be diagnosed with muscle biopsy and electromyographic findings exclusively. In our case, the patient showed similar clinical manifestations of distal SMA. So we couldn't diagnose this case as SMA type III until we detected SMN 1 gene deletion. This case could be a good model for diagnostic approach to SMA type III and differential diagnosis to similar diseases.

Keyword

Motor neuron disease; Proximal spinal muscular atrophy type III; Survivor motor neuron gene

MeSH Terms

Anterior Horn Cells
Atrophy
Biopsy
Denervation
Diagnosis, Differential
Extremities
Gene Deletion
Humans
Motor Neuron Disease
Motor Neurons
Muscle Weakness
Muscular Atrophy
Muscular Atrophy, Spinal*
Muscular Diseases
Muscular Dystrophies
Neuronal Apoptosis-Inhibitory Protein
Survivors
Neuronal Apoptosis-Inhibitory Protein