Metastasis of frontal oligoastrocytoma to cerebellar vermis.

Sir, Opsoclonus-myoclonus syndrome (OMS) is a rare but distinctive disorder, characterized by irregular, continual, and conjugated chaotic saccades of the eyes accompanied by appendicular myoclonus and truncal ataxia. No etiological factor can be found in 50% of adult cases. In 20% of cases it may be paraneoplastic and may also be a manifestation of brainstem stroke or infection. The most common tumors, which give rise to OMS are breast and lung cancers and infectious agents are Epstein-Barr virus and enteroviruses such as Coxackie B. A 41-year-old woman presented with severe vertigo and gait unsteadiness for ten days. There was no history of any antecedent viral infection or vaccination. Neurological examination revealed coarse eye movements with severe truncal ataxia and limb myoclonus. Laboratory examination (routine hematological tests, urine and cerebrospinal fluid examination, serological tests for infections, oncological bands workup, magnetic resonance imaging of brain and electroencephalography) revealed no abnormality. As assays for paraneoplastic antibodies couldn’t be performed due to technical limitations, the patient was considered to be a case of idiopathic OMS. Therapeutic trial with prednisolone (1 mg/kg/orally) and clonazepam (4 mg/day) was attempted. Because of the lack of any beneficial effect, intravenous immunoglobulin (IVI g) (0.4 g/kg/day for five days) was added on the sixth day and Prednisolone and clonazepam were tapered in the following five days. On the third day of IVI g treatment, muscle jerking and eye movements stabilized. She began to sit without assistance and during the next two weeks the patient gradually recovered. She was symptom free within eight weeks. Physical symptoms and repeated laboratory examinations for occult malignancy after one-year interval was negative. She has been asymptomatic for two years. The response to immunotherapy is unclear in paraneoplastic and idiopathic OMS, because the rarity of this disorder hinders controlled clinical studies and the possibility of spontaneous remissions makes interpretation difficult in isolated cases. In adults under 40 years of age, the clinical evolution is more benign and the effect of IVI g seems more effective. IVI g is an immunmodulating agent that has multiple activities, including neutralization of pathogenic autoantibodies, suppression of inflammatory mediators, complement inactivation, functional blockage of Fc receptors on macrophages and modulation of T-cell functions. Treatment with IVI g has been reported in a few idiopathic adult-onset OMS cases in literature. Pless et al. first reported beneficial effects of IVI g in 1996. Bataller et al analyzed 10 idiopathic and 14 paraneoplastic adult OMS patients. IVI g was used in five of the idiopathic cases. They concluded that idiopathic OMS presents an age dependent prognosis and immunotherapy seems to be associated with a faster recovery. Our case suggests that patients with idiopathic OMS treated with IVI g may have a faster recovery and this treatment should be recommended in cases with severe neurological dysfunction.