Cree leukoencephalopathy and other leukoencephalopathies involving arcuate fibers.

Abstract

Editor: We read with great interest the article by Dr Alorainy and colleagues in the November 1999 issue of Radiology (1). The authors nicely presented computed tomographic and magnetic resonance (MR) imaging findings of a rare and lethal disorder, Cree leukoencephalopathy, in 12 patients whose diagnoses were made clinically or at autopsy. They concluded that Cree leukoencephalopathy caused striking symmetric and diffuse involvement of cerebral and cerebellar white matter and brainstem, with sparing of the caudate nucleus and putamen. They also stated that radiologic findings are complementary to clinical findings in establishing the diagnosis. In the differential diagnosis, Dr Alorainy and colleagues discussed various disorders in which white matter is diffusely involved. However, it is possible to lengthen the differential diagnosis list. Van der Knapp leukoencephalopathy is among the disorders in which diffuse white matter involvement with sparing of basal ganglia is seen. In this disorder, the children are macrocephalic, and neurologic symptoms appear gradually over years (2). Vanishing white matter disease is another disorder that diffusely involves white matter, including arcuate fibers (3). This disorder may be seen after a minor infection, as in Cree leukoencephalopathy, but the clinical course is slower and its onset is later. Besides these two disorders, a similar involvement pattern may also be seen in some of the disorders proposed as leukoencephalopathies of unknown origin. These disorders have been categorized by Van der Knaap et al (4), and category B leukoencephalopathy shows global cerebral white matter involvement with sparing of the putamen. The disorders in category B leukoencephalopathies may be considered in the differential diagnosis of Cree leukoencephalopathy.