[Diseases other than Parkinson's disease presenting with parkinsonism]

Among the diseases causing parkinsonism, drug-induced parkinsonism is important because physicians often use anti-dopaminergic drugs such as benzamides for gastrointestinal disorders. In 28 patients with drug-induced parkinsonism, 13 (47%) showed persistent parkinsonism even 6 months after the cessation of the causative drugs. This means anti-dopaminergic drugs may bring subclinical parkinsonism to the clinical level especially in the elderly. Progressive supranuclear palsy (PSP), corticobasal degeneration (CBD) and multiple system atrophy including striatonigral degeneration were recognized in 2003 as specific diseases by the National Health Insurance of Japan. The diagnostic criteria of PSP (the modification of NINDS-SPSP criteria) made by the study group of the Ministry of Health, Welfare and Labour (MHWL) of Japan has demonstrated that their sensitivity was 83% and specificity 97% in "probable PSP". Patients with CBD were surveyed among the main neurologic institutions in Japan using the provisional diagnostic criteria There were 151 patients with "probable CBD" and 13 with "definite CBD". Based on these data, the number of patients with PSP and CBD in 2001 was estimated as 6,400 (5.03 per 100,000) and 2,500 (1.93 per 100,000), respectively, in Japan. Neuroprotective drugs hold hope for the treatment of neurodegenerative diseases. Although many agents were reported to be neuroprotective for Parkinson's disease from in vitro studies, pramipexole, a dopamine agonist, is the only one with good clinical evidence based on neuroimaging. Other dopamine agonists as well as various nerve trophic factors may also have the same effects, though further confirmatory studies are necessary.