We report a 55-year-old woman who developed symptoms resembling
parkinsonism. Her psychiatric symptoms in the early stage,
cervical dystonia and
tremor increasing on movement were consistent with
manganese poisoning.
Manganese levels were elevated to 1.5 micrograms/l in the serum (normal; 0.3-1.1 micrograms/l) and to 1.4 micrograms/l in the urine (normal; less than 1.2 micrograms/l).
Intravenous infusion of
calcium disodium editate (CaEDTA;
chelating agent) was followed by the marked excretion of
manganese (27.3 micrograms/l) in the urine. These findings support
manganese poisoning.
Manganese poisoning is a disease which results from chronic exposure to
manganese, but the source of
manganese exposure remained obscure in this patient. T1-weighted MRI of the brain showed symmetric high signal intensity in the globus pallidus without any abnormality on T2-weighted images. There is a report that
manganese induced brain lesions in Macaca fascicularis as revealed by MRI and the fascicularis developed signs of
unsteady gait and hypoactivity. The patient responded to treatment with CaEDTA and the second MRI demonstrated regression of abnormal signal intensity. This may be due to enhanced
manganese excretion. To our knowledge, this is the first case of probable
manganese-induced human
parkinsonism whom changes in MRI were noted
after treatment with CaEDTA.