- Ospclonus-myoclonus syndrome is a rare disorder that affects the nervous system.
- The onset of the syndrome is often abrupt and severe, moreover, the disease may become chronic.
- The syndrome is usually associated with neuroblastomas or bacterial and viral infection .
A 71-year-old man with hypertension and an alcohol use disorder presented to the clinic with a 3-month history of vertigo, diplopia and ataxia and was diagnosed with opsoclonus-myoclonus syndrome. To examine the nervous system of the patient, a neurological exam was performed which showed signs of ataxia, dysarthria, action tremor and myoclonus of the proximal leg. Furthermore, the patient had rapid, nonrhythmic, saccadic and multidirectional ocular movements. The findings were consistent with the diagnosis of a condition referred to as opsoclonus (see video).
The initial laboratory test results, including thiamine tests were normal. A lumbar puncture was performed to analyse the cerebrospinal fluid which was negative for any infection and showed 8 nucleated cells per microliter (reference value, ≤5), a protein level of 88 mg per deciliter (reference value, ≤35), and 5 oligoclonal bands (reference value, <4). Although, the patient’s serum was positive Ma2 IgG antibodies.
For further evaluation, the patient was advised magnetic resonance imaging (MRI) of the head. However, the findings on the MRI were unremarkable with no evidence of cancer was found on fluorodeoxyglucose positron-emission tomography.
The patient was diagnosed with opsoclonus–myoclonus syndrome due to anti-Ma2 brain-stem encephalitis.
Opsoclonus-myoclonus is a rare syndrome that affects the nervous system. It may be associated with an autoimmune disorder that affects the brain stem in adults and cause rapid, multi-directional eye movements (opsoclonus), myoclonic jerks (involuntary muscle jerks), ataxia (uncoordinated movement), sleep disturbance and irritability.
The patient was started on treatment with glucocorticoids, plasma exchange and rituximab with abatement of opsoclonus and myoclonus. However, the ataxia of the patient progressed, despite receiving additional therapy with cyclophosphamide.
The patient was on a wheelchair a year after presentation .
- Opsoclonus-myoclonus syndrome https://rarediseases.info.nih.gov/diseases/10009/opsoclonus-myoclonus-syndrome
- Opsoclonus in Anti-Ma2 Brain-Stem Encephalitis https://www.nejm.org/doi/full/10.1056/NEJMicm1914516