|Leukoencephalopathy with vanishing white matter
This leukoencephalopathy is an autosomal recessive disorder with chronic progression and additional episodes of rapid deterioration, provoked by fever and minor head trauma. Patients have normal development in early childhood, then develop progressive ataxia. This is a primary axonopathy, with myelin being secondarily affected. Mutations are identified in the eukaryotic translation initiation factor (eIF2B) which is essential for the initiation of translation of RNA into protein and is involved under circumstances of stress. Increased cerebrospinal glycine may be secondary to excitotoxic brain damage (30).
Pathology shows axonal loss, hypomyelination, demyelination, and gliosis, primarily in subcortical white matter. Typical MRI findings are diffuse white matter signal hyperintensity on T2-weighted images similar to CSF intensity with additional lesions in the central tegmental tracts and basis pontis (Figure 12). MRS shows mildly increased lactate and glucose peaks with decreased NAA, choline and creatine peaks (31).
Figure 12. An 11 year-old male with vanishing white matter disease.
A. T2WI shows diffuse white matter hyperintensity similar to CSF intensity.
B. MRS (TE 144 ms, PRESS) shows inverted lactate peaks and decreased NAA.
C. MRS (TE 35 ms, PRESS) shows increased lactate and glucose.