MR spectroscopy in 18q(-) syndrome suggesting other than hypomyelination.

We reported a 5-year-old boy with 18q(-) syndrome who showed typical magnetic resonance imaging (MRI) findings of high signal intensity on T2-weighted imaging, and a slightly high but lower than normal signal on T1-weighted imaging of the white matter. MR spectroscopy (MRS) revealed increased concentrations of creatine, myoinositol and choline with a normal N-acetylaspartate one. The cerebral white matter lesions observed on MRI in patients with 18q(-) syndrome have been considered to reflect hypomyelination due to a decrease in myelin basic protein so far, however, MRS suggested reactive astrocytic gliosis and accelerated myelin turnover, which are compatible with recent pathological reports of 18q(-) syndrome.