[Genetically confirmed spinal muscular atrophy type III with epilepsy, cerebral hypoperfusion, and parahippocampal...

We report a 37-year-old female with spinal muscular atrophy (SMA) type III and central nervous system (CNS) involvement. She showed gait disturbance at the age of 12 years, and difficulty of squatting at the age of 19. On examination at the age of 22, she had proximal muscle weakness and atrophy, fasciculation, normal sensory system and elevated creatine kinase in the serum. She was diagnosed as having SMA type III based on clinical, electrophysiological, and muscle biopsy findings. She suffered from subacute necrotizing lymphadenitis at the age of 23 and from epilepsy at the age of 33. Magnetic resonance imaging showed atrophy of parahippocampal gyrus with right side predominance. Single photon emission computed tomography (SPECT) using I123-IMP showed decreased accumulations of I123-IMP in the temporal lobes with left side predominance. Electroencephalogram showed theta wave without epileptic burst. SMA gene analysis revealed deletion of exon 7 and 8 in survival motor neuron (SMN) gene. A few patients with SMA and CNS involvement have been reported without genetic diagnosis. This is the first report of genetically confirmed SMA patient with CNS involvement. SMN gene is distributed not only in spinal cord but also in brain. The CNS involvement detected in this patient may be related to the loss of SMN gene function, although coincidental association of SMA and the CNS abnormalities is still considered in this atypical case.