OBJECTIVETo analyze and review the characteristics of leukoencephalopathy with vanishing white matter (VWM).

METHODSThe clinical features including clinical manifestations, neurologic signs, cranial MRI and laboratory tests in 9 patients with the diagnosis of VWM were analyzed and the characteristics of the disease were reviewed.

RESULTS

CLINICAL MANIFESTATIONS8 cases had symptoms involving central nervous system, 1 case only showed abnormal cranial MRI findings. The onset of the disease occurred between 6 months to 3 years of age. Family history was positive in 5 cases. Almost all cases had normal psychomotor development before the onset of the disease. The initial symptom was usually movement disorder with predominant involvement of lower limbs. The onset or deterioration of the disease was followed by respiratory tract infection in 6 cases and minor head trauma preexisted in 3 cases. The course of the disease was progressive in 7 cases and there was episodic deterioration in 4 cases. Mental abilities were relatively better preserved. Head circumference was normal in 7 cases. Positive upper motor unit signs were found in 8 cases and ataxia in 4 cases. Bilateral optic nerve atrophy was found in 3 cases. Cranial MRI indicated diffuse and symmetrical involvement of deep white matter which showed long T(1) and T(2) signal. Subcortical white matter was also involved with predominance in frontal and parietal lobes. Flair image showed symmetrical high signal intensity in cerebral white matter with low signal intensity similar to that of CSF in partial area or low signal in most area of white matter with only meshwork of higher signal preserved. The results of all the laboratory tests including the enzyme and biochemical test specific for some well-known leukoencephalopathy were normal.

CONCLUSIONSThe clinical features of VWM include: 1. Initial symptom is usually movement disorder; 2. Movement disorder is more prominent compared to mental retardation; 3. Cranial MRI shows symmetrical abnormal T(1) and T(2) signal in deep white matter with signs of vanishing white matter. Exclusion of other hereditary and acquired leukoencephalopathy is necessary for diagnosis. Final diagnosis should be made on the basis of genetic evidence.