Clinical features and outcomes of opsoclonus myoclonus ataxia syndrome

Exploring the Symptoms of and Insights Into Idiopathic Opsoclonus-Myoclonus-Ataxia Syndrome in Adults

Opsoclonus-myoclonus-ataxia syndrome (OMAS) is a rare immunological central nervous system disorder that mostly affects children, and it is extremely uncommon in adults. It usually presents idiopathically, as a parainfectious condition, or as a paraneoplastic syndrome. We present a case of a patient who developed adult-onset opsoclonus-myoclonus-ataxia syndrome (OMAS) without any associated infectious or neoplastic disease, a condition that is considered very rare in Central America. This study aimed to document a rare case of adult-onset opsoclonus-myoclonus-ataxia syndrome in a 39-year-old female, highlighting its atypical presentation and the diagnostic challenges involved. The patient presented with a one-week history of rapid-onset and progressive dizziness, nausea, and vomiting, associated with a two-day history of gait instability, memory loss, and sleep disturbances. Past medical history was only notable for psoriatic arthritis controlled with methotrexate. The neurologic examination revealed involuntary, rapid, multidirectional eye saccades consistent with opsoclonus, fast-twitching and jerking movements of the head and bilateral upper extremities consistent with myoclonus, and a wide-based gait with instability indicative of ataxia, suggesting a diagnosis of OMAS. There were no motor or sensory deficits, seizures, fever, or symptoms suggestive of infections. Brain magnetic resonance imaging and computed tomography scan of the head, neck, thorax, abdomen, and pelvis with and without contrast showed no abnormalities. Breast, abdomen, and gynecologic ultrasound, esophagogastroduodenoscopy, and colonoscopy showed no lesions suggestive of underlying neoplasia. Cerebrospinal fluid (CSF) analysis showed mild hyperproteinorrhachia and lymphocytic pleocytosis, along with oligoclonal bands. Viral, bacterial, and autoimmune encephalitis panels were negative. CSF bacterial, mycobacterial, and fungi cultures were negative. Serum viral serologies, tumor markers, and antineuronal antibodies were negative. The patient received treatment with plasmapheresis, intravenous immunoglobulin, and methylprednisolone, with significant but partial improvement of her symptoms.

An unusual case of early onset opsoclonus-myoclonus syndrome: Case report and literature review

Opsoclonus-myoclonus syndrome is a rare neurological condition characterized by opsoclonus, myoclonus, ataxia, irritability, and sleep disturbances. In pediatric patients, symptoms usually start between 16 and 18 months of age; opsoclonus-myoclonus syndrome presentation in children under 6 months is rare. Approximately 50% of cases are associated with neuroblastoma. We report an early onset presentation of opsoclonus-myoclonus syndrome in a previously healthy, 3-month-old female infant. The diagnostic workup revealed no abnormalities. The patient underwent monthly cycles of dexamethasone pulses and intravenous immunoglobulin with a favorable response. After a few months, the patient presented intermittent opsoclonus before the next scheduled pulse so from the 9th cycle onwards, the intravenous immunoglobulin dose was increased to 2 g/kg. After 9 months of treatment, she was diagnosed with a latent Mycobacterium tuberculosis infection. Due to this infection, dexamethasone pulses were discontinued, and intravenous immunoglobulin treatment was maintained with clinical improvement The patient received 18 intravenous immunoglobulin cycles, leaving her with a score of one on the Mitchell-Pike scale. Developmental milestones have been attained according to age. Despite the range of therapeutic options for managing opsoclonus-myoclonus syndrome described in the literature, the efficacy of these available therapies needs to be better established. A modified upfront approach with dexamethasone and intravenous immunoglobulin could be an option in settings where rituximab is unavailable.

Brain Volumes in Opsoclonus-Myoclonus Ataxia Syndrome: A Longitudinal Study

INTRODUCTION

Little is known about the longitudinal trajectory of brain growth in children with opsoclonus-myoclonus ataxia syndrome. We performed a longitudinal evaluation of brain volumes in pediatric opsoclonus-myoclonus ataxia syndrome patients compared with age- and sex-matched healthy children.

PATIENTS AND METHODS

This longitudinal case-control study included brain magnetic resonance imaging (MRI) scans from consecutive pediatric opsoclonus-myoclonus ataxia syndrome patients (2009-2020) and age- and sex-matched healthy control children. FreeSurfer analysis provided automatic volumetry of the brain. Paired t tests were performed on the curvature of growth trajectories, with Bonferroni correction.

RESULTS

A total of 14 opsoclonus-myoclonus ataxia syndrome patients (12 female) and 474 healthy control children (406 female) were included. Curvature of the growth trajectories of the cerebral white and gray matter, cerebellar white and gray matter, and brainstem differed significantly between opsoclonus-myoclonus ataxia syndrome patients and healthy control children (cerebral white matter, P = .01; cerebral gray matter, P = .01; cerebellar white matter, P < .001; cerebellar gray matter, P = .049; brainstem, P < .01).

DISCUSSION/CONCLUSION

We found abnormal brain maturation in the supratentorial brain, brainstem, and cerebellum in children with opsoclonus-myoclonus ataxia syndrome.

Five Years Follow-up of Opsoclonus-Myoclonus-Ataxia Syndrome-Associated Neurogenic Tumors in Children

AIM

 Opsoclonus-myoclonus-ataxia syndrome (OMAS) is a rare autoimmune disorder. Approximately half of the cases are associated with neuroblastoma in children. This study's aim is to review management of our cases with OMAS-associated neuroblastoma for treatment approach as well as long-term follow-up.

METHODS

 Age at onset of symptoms and tumor diagnosis, tumor location, histopathology, stage, chemotherapy, OMAS protocol, surgery, and follow-up period were evaluated retrospectively in six patients between 2007 and 2022.

RESULTS

 Mean age of onset of OMAS findings was 13.5 months and mean age at tumor diagnosis was 15.1 months. Tumor was located at thorax in three patients and surrenal in others. Four patients underwent primary surgery. Histopathological diagnosis was ganglioneuroblastoma in three, neuroblastoma in two, and undifferentiated neuroblastoma in one. One patient was considered as stage 1 and rest of them as stage 2. Chemotherapy was provided in five cases. The OMAS protocol was applied to five patients. Our protocol is intravenous immunoglobulin (IVIG) 1 g/kg/d for 2 consecutive days once a month and dexamethasone for 5 days (20 mg/m2/d for 1-2 days, 10 mg/m2/d for 3-4 days, and 5 mg/m2/d for the fifth day) once a month, alternatively by 2-week intervals. Patients were followed up for a mean of 8.1 years. Neuropsychiatric sequelae were detected in two patients.

CONCLUSION

 In tumor-related cases, alternating use of corticosteroid and IVIG for suppression of autoimmunity as the OMAS protocol, total excision of the tumor as soon as possible, and chemotherapeutics in selected patients seem to be related to resolution of acute problems, long-term sequelae, and severity.

[Paraneoplastic opsoclonus-myoclonus syndrome]

Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disorder characterized by a combination of main symptoms: opsoclonus, myoclonus, ataxia, psychoemotional and behavioral disturbances. OMS can develop in children as a result of immunopathological processes against the background of infectious or oncological pathology and lead to persistent neurological deficit. A case of ten-year observation of paraneoplastic OMS associated with neuroblastoma in a child is presented. Within 6 months, the clinical picture of OMS was not full and manifested by recurrent cerebellar ataxia and psychoemotional disorders. The appearance of opsoclonus against the background of increased disturbances in statics and coordination made it possible to diagnose OMS and suggest its paraneoplastic genesis. The peculiarity of the case is the combination of opsoclonus with the development of a symptomatic epileptiform ictus. Surgical treatment of neuroblastoma, immunosuppressive therapy in combination with nootropic and symptomatic anticonvulsant therapy have shown effectiveness and led to stabilization of the condition, regression of cerebellar symptoms and restoration of the rate of mental development. The long course of OMS with the gradual formation of a complete symptom complex complicates timely diagnosis of the underlying disease. Cases of cerebellar ataxia, myoclonus and abnormal eye movements, regardless of the severity and sequence of development of the clinical picture, require an interdisciplinary diagnostic approach and consideration of oncological pathology in a differential diagnostic aspect.

Cervical Ganglioneuroblastoma Diagnosed by 68Ga-DOTATOC PET/CT in a Child with Opsoclonus Myoclonus Syndrome

We performed a 68Ga-DOTATOC PET/CT scan on a 25-mo-old female patient who presented with opsoclonus myoclonus ataxia syndrome and had negative initial anatomic imaging. The scan showed a somatostatin receptor-overexpressing cervical tumor in favor of a cervical neuroendocrine tumor, with subsequent histopathologic findings of ganglioneuroblastoma.