Unexpected aggravation of Parkinson?s disease by a mesencephalic multiple sclerosis lesion

Abstract

Sirs: The association of multiple sclerosis (MS) with Parkinsonism is rare [2, 4, 5, 7, 9, 11, 13, 14]. Two hypotheses might account for the parkinsonian features. The first one is the fortuitous occurrence of Parkinson’s disease (PD) in patients with MS or vice versa. However, in a series of 368 successive PD patients, none of them displayed MS [1]. The second hypothesis postulates that Parkinsonism is due to MS. In six patients with MS and Parkinsonism, a MS lesion may have affected dopaminergic pathways, supporting the link between Parkinsonism and MS [4, 13, 14]. Moreover, Federlein et al. [4] reported an almost complete disappearance of parkinsonian symptoms after a corticosteroid treatment. We present the case of a patient with PD associated with a MS lesion affecting the left nigrostriatal pathway, and postulate that this lesion aggravated the PD. Case report. A 38 year-old woman with no particular medical history presented with progressive gait instability. One year after onset of the symptoms, neurological examination showed a right-sided akineto-rigid parkinsonian syndrome without tremor, which improved significantly under levodopa treatment (200 mg/day). Neurological examination was otherwise normal. A diagnosis of PD was proposed. The patient’s mother and grandmother suffered from Parkinson’s disease and her sister was presumed to have MS. Brain MRI was normal. One year later, the asymmetrical akinetorigid syndrome had notably progressed. When the patient was “off”, the Unified Parkinson’s Disease Rating Scale (UPDRS) score [3] was 29/108 (right hemibody: 11/36; left hemibody: 4/36; no tremor). Two hours after ingestion of 200 mg of levodopa, the score was 11/108. Neurological examination showed bilateral brisk reflexes and Babinski signs but was otherwise normal. A second brain MRI showed periventricular T2hyperintense signal abnormalities of white matter, without enhancement by gadolinium. One of the lesions was localized in the left cerebral peduncle, in the medial part of the substantia nigra (Figure). Cerebrospinal fluid (CSF) examination showed 10 leucocytes/mm3 and intrathecal synthesis of IgG with oligoclonal bands. A diagnosis of MS was proposed. However, three intravenous infusions of 1 g of methylprednisolone did not improve motor disability. Two years later, a third MRI of the brain showed several new white matter abnormalities. The largest one was enhanced by gadolinium. Positron emission tomography (PET) study of the brain with 18FL-DOPA showed a hypometabolic pattern over 3.5 standard deviations for the caudate nuclei, over 7 standard deviations for the right putamen and over 9 standard deviations for the left putamen [10]. The hypometabolism predominated in the posterior third of the putamen. The diagnosis of early onset PD is supported by a characteristic asymmetrical akineto-rigid syndrome and a good response to levodopa. The demyelinating brain lesions can account for the BabinLETTER TO THE EDITORS