Leukoencephalopathy with vanishing white matter
Evanescent white matter leukoencephalopathy is one of the most prevalent childhood leukoencephalopathies, with autosomal recessive inheritance. It not only affects children, but can also affect people of all ages, including neonates and adults. It is a progressive disorder that produces cerebellar ataxia and in which minor stress conditions, such as fever or mild trauma, lead to major episodes of neurological impairment.
The classic and most frequent variant has its onset in childhood, most often between the ages of 2 and 6 years. According to centralized data in the Netherlands, the prevalence is estimated at 1.4 cases per 1,000,000 people.
Symptoms
Vanishing white matter leukoencephalopathy is characterized by progressive chronic neurological deterioration with cerebellar ataxia and relatively mild mental decline. Epilepsy is present in most patients, but is rarely a prominent feature and, in some cases, vision loss due to optic atrophy may occur. After a mild head injury or a febrile infection, there may be episodes of faster and greater deterioration of motor faculties.
When symptoms are of early onset they are more severe, and include feeding problems, vomiting, failure to thrive, irritability, apathy, axial hypotonia, hypertonia or hypotonia of the limbs, seizures and respiratory failure, among others.
At the other end of the clinical spectrum are adult-onset patients. In some patients, occasional seizures are the first symptom, while in others, the disease begins with psychiatric symptoms or motor impairment.
Disease management
There is no cure for vanishing white matter leukoencephalopathy; treatment aims to control symptoms and improve the patient's quality of life. Corticosteroids can sometimes be useful in the acute phases to prevent cellular stress. Symptomatic treatment includes medication to control seizures and muscle stiffness. Physical therapy is also proposed to improve coordination and movement; and occupational therapy to facilitate the patient's performance of routine activities.
Genes analyzed
Bibliography
Lee, H. N., Koh, S. H., Lee, K. Y., et al. Late-onset vanishing white matter disease with compound heterozygous EIF2B5 gene mutations. European journal of neurology. 2009 Mar;16(3):e42-3.
Leegwater, P. A., Vermeulen, G., Könst, A. A., et al. Subunits of the translation initiation factor eIF2B are mutant in leukoencephalopathy with vanishing white matter. Nature genetics. 2001 Dec;29(4):383-8.
Ohtake, H., Shimohata, T., Terajima, K., et al. Adult-onset leukoencephalopathy with vanishing white matter with a missense mutation in EIF2B5. Neurology. 2004 May 11;62(9):1601-3.
van der Knaap, M. S., Leegwater, P. A., van Berkel, C. G., et al. Arg113His mutation in eIF2Bepsilon as cause of leukoencephalopathy in adults. Neurology. 2004 May 11;62(9):1598-600.
