[Monoamine imbalance of the central nervous system in a case of Shy-Drager syndrome with recurrent attacks of a neuroleptic malignant syndrome].

A 79-year-old male suffering from Shy-Drager syndrome was treated with a daily dosage of 300 mg of L-threo-3,4-dihydroxyphenylserine (L-DOPS). He developed a neuroleptic malignant syndrome (NMS) like state 1 month after teh initiation of L-DOPS therapy. And recurrent attacks of NMS occurred subsequently despite discontinuation of L-DOPS administration. We measured homovanillic acid (HVA), 3 methoxy 4 hydroxyphenylethylenglycol (MHPG), and 5-hydroxyindoleacetic acid (5-HIAA) in this corrected brospinal fluid (CSF), both during his 2 attacks of NMS and after recovery. The HVA and 5 HIAA levels after recovery were low compared with those in age-matched normal controls. However, his levels in the active phase were not different from those after recovery. In contrast, MHPG levels were elevated and his HVA/MHPG ratios decreased in the active phase compared with those in the recovery phase. The results indicate that his symptoms of NMS are attributed to the imbalance between dopamine and noradrenalin rather than the dopamine receptor blockade in the central nervous system. We suggest further evaluations of CSF monoamine metabolites in similar cases to determine the pathogenesis of NMS.