Opsoclonus-myoclonus syndrome in adults: a report of two cases

Abstract

Background: Opsoclonus-myoclonus syndrome (OMS) is a rare movement disorder characterized by chaotic multidirectional eye movements, myoclonus and less frequently cerebellar ataxia. OMS affects as few as 1 in 10,000,000 people per year. Case reports: We present two cases of female Caucasian patients aged 19 and 60 years respectively who developed OMS following a febrile illness. In both cases OMS starts with an acute flare-up of physical symptoms within days. The neurologic examination revealed opsoclonus, myoclonus and ataxia. Both women had normal magnetic resonance imaging of the brain. The results of routine laboratory tests were normal. In both cases, cerebrospinal fluid examinations was consistent with aseptic meningoencephalitis and showed cell-protein association (lymphocytic pleocytosis and protein elevation). The oligoclonal IgG band was negative. Cytomegalovirus, Epstein-Bar virus, Varicella-zoster virus, borrelia, coxsackie, enterovirus, streptococcal infection, syphilis, herpes simplex virus-1 and -2, human immunodeficiency virus or hepatitis were negative in the serological tests. The thyroid function tests, the tests for anti-nuclear and anti-neuronal antibodies were within normal limits. Malignancy was not detected on positron-emission tomography-CT. After therapies including a combination of intravenous methylprednisonolon, intravenous ceftriaxon, acyclovir and clonazepam, both patients gradually improved and had recovered. After a 12-month follow-up, both women had no neurological sequelae. We have obtained approval of both patients. Conclusion: OMS is associated with multiple etiologies. The most common etiologies are idiopathic, paraneoplastic and infectious disorders. OMS may occur in patients with aseptic brainstem encephalitis. The exact immunopathogenesis and pathophysiology of OMS are uncertain.