More recently, Rifal and associates reviewed the findings in 25 cases of this disease—one observed by them and 24 reported previously. The dementia was relatively mild, consisting of impairment of retentive memory, dysnomia, dyscalculia, and sometimes nonfluent aphasia and deficits of “visual integration”; this was overshadowed by rigidity and spasticity of the limbs and the peripheral nerve disorder. Bladder dysfunction has been an early sign in many patients including a middle-aged woman under our care who had only diffuse white matter changes in the cerebral MRI and a moderate sensory neuropathy. Nerve conduction velocities were diminished and the leg muscles were denervated. Moderate degrees of generalized cerebral atrophy, multifocal areas of white matter rarefaction, and degeneration of the corticospinal system, disclosed by MRI. Some cases simulate motor neuron disease. The finding of polyglucosan axonal inclusion in biopsied nerves confirms the diagnosis. The disease has sometimes been misinterpreted as adrenoleukodystrophy. The disorder appears to be a glycogenosis that is allied with Anderson disease, as discussed in Chaps. 37 and 43.
Adult forms of metachromatic leukodystrophy, adrenoleukodystrophy, Krabbe disease, and neuronal ceroid lipofuscinosis (Kufs disease) may be present with a similar clinical picture of progressive dementia (see Chap. 36) as may Whipple disease (Chap. 31) or the Wernicke-Korsakoff disease (Chaps. 20 and 41). Quite rare instances of the same syndrome with adult onset have proved to be caused by phenylketonuria or other aminoacidopathies (see Chap. 36).
This common disease, known since ancient times, was first cogently described by James Parkinson in 1817. In his words, it was characterized by “involuntary tremulous motion, with lessened muscular power, in parts not in action and even when supported; with a propensity to bend the trunk forward, and to pass from a walking to a running pace, the senses and intellect being uninjured.” Strangely, his essay contained no reference to rigidity or to slowness of movement and it stressed unduly the reduction in muscular power. The same criticism can be leveled against the term paralysis agitans, which appeared for the first time in 1841 in Marshall Hall’s textbook Diseases and Derangements of the Nervous System and has fallen out of use, but was such a common term in the literature that it is mentioned here.