Family with dominantly inherited ataxia, amyotrophy, and peripheral sensory loss. Spinopontine atrophy or Machado-Joseph Azorean disease in another non-Portuguese family?
K. Eto, S. M. Sumi, T. D. Bird, T. McEvoy-Bush, M. Boehnke and G. Schellenberg
Department of Pathology (Laboratory of Neuropathology), University of Washington School of Medicine, Seattle 98195.
A family of German extraction with progressive ataxia, eye movement
abnormalities, peripheral sensory loss, and spinal muscular atrophy of
adult onset is described. Three members came to autopsy, and
neuropathologically, the major changes included varying degrees of atrophy
of the basis pontis and degeneration of the spinocerebellar tracts,
Clarke's columns, anterior horn neurons, and fasciculus gracilis. The
dentate nucleus was spared, and there was slight neuron loss from the
substantia nigra in one patient. Clinically and neuropathologically, our
family resembles that reported by Boller and Segarra as having spinopontine
atrophy. However, several kindreds with similar findings have recently been
described as having Azorean or Machado-Joseph disease in non-Portuguese
families. Comparison of clinical and neuropathological features in
spinopontine atrophy and Machado-Joseph disease, both in Portuguese and
non-Portuguese families, reveals clinical and pathological similarities and
differences between the two. The major differences in our patients include
only minor extraocular movement abnormality and absence of protuberant
eyes, and muscular rigidity clinically, and the sparing of the substantia
nigra and the dentate nucleus neuropathologically. These differences
suggest that spinopontine atrophy, as manifested in our family, is distinct
from Machado-Joseph disease. Our family showed no linkage to the HLA locus
on chromosome 6.
