Primary sensory symptoms in parkinsonism.

Forty-three of 101 outpatients with parkinsonism reported that they regularly experienced primary sensory symptoms, i.e., spontaneous abnormal sensations not caused by somatic disease. This is in contrast to similar symptoms reported by only 8 percent of a control population. The most striking and severe symptom was burning of the trunk and proximal extremities, occurring in 11 patients. Twenty-nine patients reported spontaneous pain; a variety of other paresthesialike sensations, e.g., tingling, numbness, and formication, occurred in 32 patients. These subjective sensory phenomena were not associated with sensory loss or autonomic or motor signs. In 20 percent of affected individuals (9 percent of the total), sensory symptoms preceded the onset of the movement disorder, causing difficulty in diagnosis. It is concluded that at least some sensory symptoms originate within the nervous system as a manifestation of the disease process and are not secondary effects of the motor disorder.