Syndrome of opsoclonus-myoclonus caused by Coxsackie B3 infection

Acute Movement Disorders in Childhood

Acute-onset movement disorders (MDs) are an increasingly recognized neurological emergency in both adults and children. The spectrum of possible causes is wide, and diagnostic work-up is challenging. In their acute presentation, MDs may represent the prominent symptom or an important diagnostic clue in a broader constellation of neurological and extraneurological signs. The diagnostic approach relies on the definition of the overall clinical syndrome and on the recognition of the prominent MD phenomenology. The recognition of the underlying disorder is crucial since many causes are treatable. In this review, we summarize common and uncommon causes of acute-onset movement disorders, focusing on clinical presentation and appropriate diagnostic investigations. Both acquired (immune-mediated, infectious, vascular, toxic, metabolic) and genetic disorders causing acute MDs are reviewed, in order to provide a useful clinician’s guide to this expanding field of pediatric neurology.

Molecular and Clinical Comparison of Enterovirus D68 Outbreaks among Hospitalized Children, Ohio, USA, 2014 and 2018

Enterovirus D68 (EV-D68) causes respiratory tract infections and neurologic manifestations. We compared the clinical manifestations from 2 EV-D68 outbreaks in 2014 and 2018 and a low-activity period in 2016 among hospitalized children in central Ohio, USA, and used PCR and sequencing to enable phylogenetic comparisons. During both outbreak periods, infected children had respiratory manifestations that led to an increase in hospital admissions for asthma. The 2018 EV-D68 outbreak appeared to be milder in terms of respiratory illness, as shown by lower rates of pediatric intensive care unit admission. However, the frequency of severe neurologic manifestations was higher in 2018 than in 2014. During the same period in 2016, we noted neither an increase in EV-D68 nor a significant increase in asthma-related admissions. Phylogenetic analyses showed that EV-D68 isolates from 2018 clustered differently within clade B than did isolates from 2014 and are perhaps associated with a different EV-D68 subclade.

Multifactorial analysis of opsoclonus-myoclonus syndrome etiology ("Tumor" vs. "No tumor") in a cohort of 356 US children

BACKGROUND

Pediatric opsoclonus-myoclonus syndrome (OMS) presents a paradox of etiopathogenesis: A neuroblastic tumor (NB) is found in only one half of the cases, the others are ascribed to infections or designated as idiopathic.

METHOD

From an IRB-approved observational study of 356 US children with OMS, secondary analysis of "etiology" and related factors was performed on a well-characterized cohort. The "Tumor" (n = 173) and "No Tumor" groups (n = 183), as defined radiologically, were compared according to multiple factors considered potentially differentiating. Data were analyzed retrospectively using parametric and nonparametric tests as indicated.

RESULTS

Patients with NB were not distinguishable by prodromal symptoms, OMS onset age, gender, race/ethnicity, OMS severity, rank order of neurological sign appearance, or geographic distribution. Various CSF immunologic biomarker abnormalities of OMS did not vary in the presence or absence of a detectable tumor: frequency of six lymphocyte subsets, or concentrations of 18 cytokines/chemokines, cytokine antagonists, chemokine receptors, cell adhesion molecules, or neuronal/glial markers. Prior responsiveness to conventional immunotherapy was not contingent on tumor/no tumor designation.

CONCLUSIONS

Multiple convergent factors provide compelling empirical evidence and rationalize the concept that OMS is one neurological disorder, regardless of apparent etiology. Limitations to the current clinical etiologic classifications as paraneoplastic, parainfectious/post-infectious, and idiopathic etiology require antigen-based biological solutions to tease out the molecular pathophysiology of viral/tumoral mechanisms. Systematic studies, regardless of presumed etiology, will be necessary to find the highest-yield combination of imaging approaches, screening for infectious agents, and new biomarkers. Two testable hypotheses for future research are presented.

Opsoclonus Myoclonus Syndrome: A Rare Manifestation of Dengue Infection in a Child

Opsoclonus myoclonus syndrome (OMS) is an inflammatory neurological disorder, which is characterized by chaotic uncontrolled movements of the eyes and involuntary jerk-like movements of the body. Different modalities of treatment have been described in medical literature to treat OMS. Immunomodulatory treatment with either steroids or intravenous immunoglobulin has been considered. Our case was a 14-year-old boy who presented with fever, mild confusion, without any seizures or focal deficits. On examination, he had opsoclonus in his eyes and had cortical myoclonus in his hands and body. On evaluation, he had low platelets, normal metabolic workup, normal brain imaging, and cerebrospinal fluid showed lymphocytic pleocytosis. He was managed conservatively and had spontaneous improvement in opsoclonus myoclonus by 5th day of his illness and complete recovery in 2 weeks. Although dengue is primarily considered hematotropic virus, it can involve nervous system as well and manifest with OMS.

Neuroepidemiologic Trends in 105 US Cases of Pediatric Opsoclonus-Myoclonus Syndrome

Opsoclonus-myoclonus syndrome (OMS) is a rare, autoimmune neurological disorder that is poorly recognized and undertreated. Neuroblastoma is found in one half of the cases. Because of the high incidence of spontaneous regression of neuroblastoma, it is unknown whether not finding a tumor means there was none. To define demographic trends and the standard of care in the first large series of OMS, 105 children were recruited over a 13-year period in a retrospective questionnaire survey. Children with and without a tumor differed little in viral-like prodrome and neurological symptoms. Earliest neurological symptoms were staggering and falling, leading to a misdiagnosis of acute cerebellitis. Later symptoms included body jerks, drooling, refusal to walk or sit, speech problems, decreased muscle tone, opsoclonus, and inability to sleep. Tumor resection alone did not provide adequate therapy for most. Adrenocorticotropic hormone (ACTH), prednisone, and intravenous immunoglobulin were used with equal frequency, but ACTH was associated with the best early response. More than one half of the children had relapses. Residual behavioral, language, and cognitive problems occurred in the majority. The delay in diagnosis (11 weeks) and initiation of treatment (17 weeks) is unacceptably long.

Opsoclonus-myoclonus syndrome caused by varicella-zoster virus

Opsoclonus–myoclonus syndrome (OMS) is a rare condition that has been reported from all parts of the world. It is well recognized as a paraneoplastic syndrome in children with neuroblastoma and in adults with small-cell carcinoma of lung and some other cancers. It may also occur in association with various central nervous system infections. We report a case of OMS in a patient with varicella zoster virus infection. IgM antibody for varicella-zoster virus was detected in the serum and the cerebrospinal fluid. The patient improved after treatment with clonazepam and was asymptomatic at 1-month follow-up.

Neuropsychological decline/improvement in opsoclonus myoclonus ataxia

Opsoclonus myoclonus ataxia (OMA) is a rare neurological disorder (incidence = approximately 1/5 million) primarily associated with involuntary conjugate saccadic eye movements, involuntary muscle jerks, cerebellar ataxia, and neuropsychological impairments. Unfortunately, there is limited published data regarding the nature and course of neuropsychological impairments following OMA diagnosis and treatment. This study presents neuropsychological data obtained at 1, 4, and 18 months post-diagnosis of a 52-year-old male with OMA. The patient initially demonstrated significant global neurocognitive, psychomotor, and psychological difficulties with substantial improvement over time. Treatment included medication management, physical rehabilitation, and psychological intervention.

A prospective study of the presentation and management of dancing eye syndrome/opsoclonus-myoclonus syndrome in the United Kingdom

The incidence, mode of presentation and management of Dancing Eye Syndrome/Opsoclonus-Myoclonus Syndrome (DES/OMS) was prospectively evaluated in 20 United Kingdom (UK) paediatric neurology centres by questionnaire over a 24-month period between 2003 and 2005. Nineteen children were notified, giving an incidence of 0.18 cases per million total population per year. Mean age at presentation was 18 months (range 3-42 months). Fifteen families consented to participate in the study. Atypical features were present in 6/15 cases including very delayed presentation of opsoclonus, dysphagia, and rapid spontaneous improvement without treatment. Only 4/15 cases were associated with neuroblastoma (NB) but current practice in excluding this is diverse and a standardised approach is suggested.

Dancing Eye Syndrome associated with spontaneous recovery and normal neurodevelopment

Five patients with spontaneously recovering Dancing Eye Syndrome/Opsoclonus Myoclonus Syndrome are described. Age at presentation ranged from 4 to 19 months. Four had symptoms of fever and a coryzal illness within days to a few weeks prior to the onset. One of the 4 also had varicella zoster 4 weeks before presentation. All had opsoclonus, myoclonus/ataxia and irritability. Associated infective agents identified were Coxsackie virus and rotavirus. Spontaneous improvement of symptoms started within 9 days of presentation and total duration of illness ranged from 10 to 24 days. Developmental progress at follow-up was normal in all cases. A range of immunomodulatory therapies have been advocated for the treatment of Dancing Eye Syndrome/Opsoclonus Myoclonus Syndrome. However, in some children, early spontaneous recovery may occur, an observation which should be borne in mind when designing therapeutic trials in this condition.

A case of poststreptococcal opsoclonus‐myoclonus syndrome

High antistreptococcal antibody titer (ASOT) was measured in a 31-year-old Caucasian lady presenting with opsoclonus and myoclonus. She was treated with oral steroids and 8 weeks after the onset of symptoms she had a normal ASOT and only mild residual symptoms. This is one of the first cases of opsoclonus-myoclonus syndrome developing, following a streptococcal infection in adults.

An update on opsoclonus

PURPOSE OF REVIEW

The aim of this article is to review opsoclonus, with particular emphasis on its immunopathogenesis and pathophysiology.

RECENT FINDINGS

Infections (West Nile virus, Lyme disease), neoplasms (non-Hodgkin's lymphoma, renal adenocarcinoma), celiac disease, and allogeneic hematopoietic stem cell transplantation can cause opsoclonus. Newly identified autoantibodies include antineuroleukin, antigliadin, antiendomysial, and anti-CV2. Evidence suggests that the autoantigens of opsoclonus reside in postsynaptic density, or on the cell surface of neurons or neuroblastoma cells (where they exert antiproliferative and proapoptotic effects). Most patients, however, are seronegative for autoantibodies. Cell-mediated immunity may also play a role, with B and T-cell recruitment in the cerebrospinal fluid linked to neurological signs. Rituximab, an anti-CD20 monoclonal antibody, seems efficacious as an adjunctive therapy. Although changes in synaptic weighting of saccadic burst neuron circuits in the brainstem have been implicated, disinhibition of the fastigial nucleus in the cerebellum, or damage to afferent projections to the fastigial nucleus, is a more plausible pathophysiologic mechanism which is supported by functional magnetic resonance imaging findings in patients.

SUMMARY

There is increasing recognition that both humoral and cell mediated immune mechanisms are involved in the pathogenesis of opsoclonus. Further studies are needed to further elucidate its immunopathogenesis and pathophysiology in order to develop novel and efficacious therapy.

Ocular flutter induced only by optokinetic stimulation

Ocular flutter (OF) refers to occasional bursts of involuntary horizontal oscillation around the point of fixation, characterised by rapid horizontal repetitive oscillation without intersaccadic interval in electro-ocular recording. In spite of numerous reports of OF, there has been no previous report describing OF developed by simply looking at moving objects. We report a patient with olivopontocerebellar atrophy (OPCA), with OF induced only by optokinetic stimulation (OKS). A 65-year-old man, with OPCA complained of dizziness and oscillopsia occurring only with a specific type of eye movement. The electro-oculographic recording showed a decreased gain of pursuit, catch-up saccade, and decreased velocity of saccade, and OF was induced only by OKS of more than 40 degrees /second. In OPCA, partial loss of omnipause neurons and/or abnormal firing of burst neurons, especially those involved in optokinetic movement, could be the cause of OF occurring only with OKS.

Functional characterisation of autoantibodies from patients with pediatric opsoclonus–myoclonus-syndrome

Paraneoplastic opsoclonus-myoclonus-syndrome (OMS) both in children and adults is suspected to be the result of an autoimmune response directed against cross-reactive proteins of tumor and neuronal cells. We here characterised the binding and functional activities of anti-neuroblastoma antibodies in IgG fractions from 11 OMS children with and without neuroblastoma. IgG fractions from neuroblastoma without OMS (NB) and healthy children served as controls. Indirect immunofluorescence and Western blot revealed IgG binding to intracellular autoantigens in all OMS patients, but in only one of the controls (p<0.001). Using flow cytometry, we could demonstrate surface binding of IgG fractions in all OMS patients, but only in one of control (p<0.001). Moreover OMS IgG exhibited a significant anti-proliferative and a cytotoxic effect on neuroblastoma cells compared to control IgG (p<0.001 and p<0.01). TUNEL assay revealed increased apoptotic cell death of the neuroblastoma cells after exposure to OMS IgG, but not to NB or control IgG (p<0.01). Preabsorption of membrane binding abandoned the anti-proliferative effect of OMS IgG. These findings indicate that surface-binding autoantibodies are present in OMS patients and these autoantibodies cause inhibition of cell proliferation and induce apoptosis.

B- and T-cell markers in opsoclonus-myoclonus syndrome: immunophenotyping of CSF lymphocytes

BACKGROUND

Although many lines of evidence suggest an autoimmune etiology, the pathophysiology of opsoclonus-myoclonus syndrome (OMS) remains poorly understood and no immunologic abnormalities have correlated with neurologic severity. Conventional immunotherapies often do not prevent relapse or permanent sequelae.

OBJECTIVE

To test the cellular immune hypothesis of OMS in a cross-sectional study and determine if CSF lymphocyte subset analysis provides biomarkers of disease activity.

METHODS

The expression of lymphocyte surface antigens was investigated in CSF and blood of 36 children with OMS and 18 control subjects, using a comprehensive panel of monoclonal antibodies to adhesion and activation proteins in combination with anti-CD3 and anti-CD45 antibodies in four-color fluorescence-activated cell sorting.

RESULTS

Although most children with OMS had normal CSF cell counts, they exhibited expansion of CD19+ B-cell (up to 29%) and gammadelta T-cell (up to 26%) subsets and a lower percentage of CD4+ T-cells and CD4/CD8 ratio, which persisted even years after disease onset and conventional treatments. The percentage of activated CSF T-cells was also higher. Abnormalities correlated with neurologic severity, as scored blinded from videotapes using a 12-item motor scale, and disease duration. No significant differences were found between tumor and no-tumor groups. In children with neuroblastoma, tumor resection or cancer chemotherapy did not alter immunologic abnormalities.

CONCLUSIONS

CSF B- and T-cell recruitment is linked to neurologic signs in pediatric OMS, which may relate to relapses and disease progression.

Neuroblastic tumors associated with opsoclonus-myoclonus syndrome: histological, immunohistochemical and molecular features of 15 Italian cases

The aim of this study was to investigate the histological, immunohistochemical and molecular features of a series of children with neuroblastic tumors (NTs) and opsoclonus-myoclonus syndrome (OMS). Of 1187 children (age 0-15 years) with previously untreated NTs registered between 1979 and 1995, 15 (1.3%) had OMS at presentation. The majority of patients showed favorable biological characteristics, such as lack of amplification of the neuroblastoma-associated avian myelocytomatosis homolog MYCN oncogene and aneuploid nuclear DNA content. Tumor histology was reviewed according to the International Neuroblastoma Pathology Classification. Histology of the 15 cases of NTs with OMS was ganglioneuroblastoma, intermixed, in 10 patients; ganglioneuroma, maturing, in 1; and neuroblastoma in 4. Of 15 tumors, 12 (10 ganglioneuroblastomas, 2 neuroblastomas) showed abundant interstitial or perivascular lymphoid infiltrates, the latter often organized in secondary lymphoid follicles. The three remaining cases had only minimal infiltrates. A review of 91 cases of age- and stage-matched neuroblastic tumors not associated with OMS tested as controls showed that the degree of lymphoid infiltration was significantly lower than that detected in OMS-related tumors. Furthermore, lymphoid follicles were always present in the latter tumors, whereas they were detected only in a few ganglioneuroma, intermixed tumors from the control group. In conclusion, ganglioneuroblastoma, intermixed subtype, lack of MYCN amplification, aneuploid DNA content and presence of lymphoid infiltrates may contribute to favorable prognosis in NTs associated with OMS.

Acute ataxia in childhood

Acute childhood ataxia is a common cause of presentation to the pediatric emergency room or child neurologist. The primary concern on initial assessment is to exclude serious causes of this clinical syndrome, including central nervous system infections and mass lesions, while recognizing the essentially benign nature of acute ataxia in most children. Childhood ataxia can be diagnostically approached by consideration of the temporal course and presence or absence of associated neurologic abnormalities. In all forms of childhood ataxia, outcome is largely determined by etiology. In this review, the various causes and syndromes of acute ataxia in childhood are described, with discussion of diagnostic considerations and an approach to investigation, treatment, and prognosis.

Screening for autoantibodies in children with opsoclonus-myoclonus-ataxia

Various paraneoplastic autoantibodies have been linked to discrete neurologic syndromes and tumors in adults, but little is known about their incidence in children. We report a cross-sectional study of known paraneoplastic antibodies in 59 children with opsoclonus-myoclonus-ataxia, 86% of whom were moderately or severely symptomatic, and 68% of whom had relapsed at the time of testing. This total number of patients includes 18 children with low-stage neuroblastoma (tested after tumor resection), six of whom had never been treated with immunosuppressants. All were seronegative for anti-Hu, anti-Ri, and anti-Yo, the three paraneoplastic antibodies most associated with opsoclonus-myoclonus or ataxia in adults. These data contrast with reports of anti-Hu-positive sera in children with high-stage tumors and suggest that anti-Hu, anti-Ri, and anti-Yo do not explain relapses in pediatric opsoclonus-myoclonus-ataxia. They underscore the need to search for unique autoantibodies, as well as cellular mechanisms of pediatric paraneoplastic disease.

Opsoclonus Myoclonus Syndrome A Case Report of Two Patients and Review of the Literature

Opsoclonus myoclonus syndrome (OMS) is a very rare syndrome which presents with ataxia, opsoclonus and myoclonus. We report the combined treatment of immunoglobulins and prednisolone compared to prednisolone alone in two patients. The diagnosis was based on the clinical findings. Work up for neuroblastoma was negative in both patients. Prednisolone treatment in the first patient was associated with slow response, relapses and toxic side effects. Immunoglobulins combined with prednisolone in the second patient were effective with neither relapse nor drug side effect. The clinical findings, differential diagnosis and the management are discussed. It appears that combined therapy with prednisolone and immunoglobulin gives better results. To the best of our knowledge this is first paper from the Middle East reporting this syndrome.

Neurological manifestations of enterovirus 71 infection in children during an outbreak of hand, foot, and mouth disease in Western Australia

Enterovirus 71 (EV71) causes epidemics of hand, foot, and mouth disease associated with neurological complications in young children. We report an outbreak of EV71-associated neurological disease that occurred from February through September 1999 in Perth, Western Australia. Fourteen children with culture-proven, EV71-induced neurological disease were identified. Nine patients (64%) developed severe neurological disease; 4 of these patients developed long-term neurological sequelae. Neurological syndromes included aseptic meningitis, Guillain-Barré syndrome, acute transverse myelitis, acute cerebellar ataxia, opso-myoclonus syndrome, benign intracranial hypertension, and a febrile convulsion. Clinical and magnetic resonance imaging data indicated that immunopathology was a major factor in the pathogenesis of neurological disease in this outbreak. This finding is in contrast to reports of previous EV71 epidemics, in which virus-induced damage to gray matter was the most frequent cause of neurological disease.

Antineuronal antibodies in patients with neuroblastoma and paraneoplastic opsoclonus-myoclonus

PURPOSE

To identify serologic markers in children with paraneoplastic opsoclonus-myoclonus (POM).

MATERIALS AND METHODS

We examined the sera of 64 children with neuroblastoma (16 with POM and 48 age-matched and stage-matched controls) by immunohistochemistry of rat brain and human cerebellum, and by Western blot analysis of protein extracts from human Purkinje cells, cortical neurons, neuroblastoma cell lines, and HuD.

RESULTS

Using immunohistochemistry, IgG reactivity against neurons was identified in 13 of 16 POM sera (81%), and 12 of 48 non-POM sera (25%; P<0.001). IgM antineural antibodies were present in 3 of 16 POM sera (19%) and 11 of 48 (23%) non-POM sera. Except for anti-Hu antibodies detected in 10 sera (4 with POM), no other specific reactivities were identified by Western blot analysis of neuronal or of neuroblastoma protein extracts.

CONCLUSIONS

We conclude that: 1) patients with neuroblastoma and POM are more likely to harbor antineuronal antibodies than patients without POM; 2) no specific serologic marker of POM was identified, but the frequent presence of antineuronal antibodies suggests that POM is immune-mediated; and 3) anti-Hu antibodies are present in some sera from patients with neuroblastoma, irrespective of the presence of POM.

Multiple sclerosis, acute disseminated encephalomyelitis, and related conditions

Multiple sclerosis (MS) and acute disseminated encephalomyelitis (ADEM) are conditions whose closely related pathology suggests shared pathophysiological elements, but whose clinical courses are usually, but not always quite dissimilar. The former is largely a disease of adulthood, the latter of childhood. Optic neuritis, demyelinative transverse myelitis, and Devic's syndrome are neurological syndromes that may occur as manifestations of either MS or ADEM. Patients with Miller-Fisher syndrome and encephalomyelradiculoneuropathy usually have features suggesting ADEM in combination with acute demyelinative polyneuropathy. These various conditions and other forms of ADEM share an indistinct border with encephalitides, granulomatous, and vasculitic conditions. MS, ADEM, and the pertinent syndromic subtypes, their differential diagnosis, treatment, and prognosis are considered in this review. Acute cerebellar ataxia is a syndrome that is likely to be pathophysiologically distinct from ADEM, although its occurrence as a postinfectious illness suggests a distant kinship. It is also reviewed.

Abnormal supranuclear eye movements in the child: a practical guide to examination and interpretation

Abnormal eye movements in the infant or voting child can be congenital or acquired. They may be a result of abnormal early visual development or a sign of underlying neurologic or neuromuscular disease. It is important to be able to detect these abnormalities and to distinguish them from normal but immature eye movements. The spectrum of disease in children differs from that in adults. Serious, potentially fatal but treatable disorders can be acquired in infancy, and abnormal eye movements in a sometimes apparently well child should never be labeled as congenital or benign without careful investigation. Eye movement analysis can indicate the presence of an underlying condition and help the clinician to classify different neurologic diseases. It is important to carefully examine the ocular motor system in any children at risk of neurologic disease. This review provides a practical guide to the examination and interpretation of eye movements in the child and includes recent literature on eye movement disorders of childhood. We describe supranuclear abnormalities of the ocular motor system in the order in which we would normally examine it: saccades, pursuit, convergence, vestibulo-ocular reflex, and optokinetic nystagmus. Nystagmus, internuclear ophthalmoplegia, cranial nerve abnormalities, and "miswiring" phenomena (such as Duane's syndrome and synergistic divergence) are not discussed.

Myoclonus and epilepsies

The possible associations of myoclonic phenomenae, progressive or non-progressive encephalopathies and epileptic features are reviewed, with special emphasis on pediatric age. This leads to recognize the following five groups of conditions: (1) Myoclonus without encephalopathy and without epilepsy; (2) Encephalopathies with non-epileptic myoclonus; (3) Progressive encephalopathies presenting myoclonus seizures of epileptic syndromes (Progressive myoclonus epilepsies); (4) Epileptic encephalopathies with myoclonic seizures; (5) Myoclonic epilepsies. Within the first group, which also includes physiologic myoclonus, a more thorough description of "Benign sleep myoclonus of newborn" and "Benign myoclonus of early infancy" is given. Characteristics of group 2 are "Kinsbourne Syndrome" and certain types of "Hyperekplexia" which pose interesting differential diagnosis with stimulus-sensitive epilepsies. In group 3, the concept of progressive encephalopathies is stressed. The fourth group refers to severe epilepsies, mainly on infancy and childhood, which lead to mental retardation irrespective of their aetiology. Group 5 comprises the true myoclonic epilepsies, differentiating syndromes recognized as idiopathic--such as "Benign myoclonic epilepsy of infancy" and "Juvenile myoclonic epilepsy"--from those which are cryptogenic and carry a more cautious prognosis--as "Cryptogenic myoclonic and myoclonoastatic epilepsies" and "Severe myoclonic epilepsy of infancy". Other epileptic syndromes not usually considered as myoclonic epilepsies, but presenting sometimes as myoclonic seizures, are finally referred.

Opsoclonus myoclonus syndrome secondary to Epstein-Barr virus infection

We report the first two children to have the "opsoclonus myoclonus syndrome" after a serologically confirmed acute Epstein-Barr virus infection. Although opsoclonus was absent in one patient, both patients had all other features typical of this syndrome. Patients without opsoclonus have been described as having an isolated postinfectious myoclonus syndrome but probably lie within the spectrum of opsoclonus myoclonus syndrome. The prognosis for the opsoclonus myoclonus syndrome in children with Epstein-Barr virus infection and without evidence for a neuroblastoma appears to be better than in those patients where a cause cannot be identified.

Central nervous system manifestations of parainfluenza virus type 3 infections in childhood

Three children were admitted within an 8-week period with parainfluenza virus type 3 infection accompanied by encephalitis. All 3 patients had electroencephalograms characterized by slowing, disorganization of background activity, and multifocal sharp-wave activity with temporal predominance. Apnea and periodic breathing were observed in 1 patient, opsoclonus-myoclonus in another, and disease mimicking herpes encephalitis in the third. All 3 patients recovered without neurologic residua.

Opsoclonus-ataxia due to childhood neural crest tumors: a chronic neurologic syndrome

Five children with subacute or acute onset of cerebellar ataxia and opsoclonus are described. Two had cerebrospinal fluid pleocytosis at the onset of ataxia and were initially thought to have acute parainfectious cerebellar ataxia of childhood. All were found to have tumors of neural crest origin (two neuroblastomas, three ganglioneuroblastomas). Tumors were small and only found by computed tomographic techniques. Urinary catecholamine metabolites were elevated in only two of the patients. Four of the five failed to improve neurologically with resection of the tumor. All four have had a steroid-sensitive chronic ataxic syndrome that worsens with acute nonspecific illnesses and has resulted in long-term deficits, particularly in speech and gross motor function. This is a metabolic encephalopathy associated with permanent residual neurologic deficits but without visible lesions on neuroimaging studies. We stress the frequency of cerebrospinal fluid pleocytosis in patients with tumor-associated opsoclonus and the clinical difficulty in separating tumor-associated cases from those due to other causes [corrected].

Opsoclonus-myoclonus syndrome: correlation of radiographic and pathological observations

We report a case of a child with opsoclonus-myoclonus syndrome. Neuroradiological studies indicated a lesion in the cerebellar vermis. A cerebellar biopsy revealed changes consisting of Purkinje and granular cell loss with gliosis. This case report documents the correlation of radiologic and pathological findings in a patient with opsoclonus-myoclonus syndrome.

Cerebellar ataxia and opsoclonus as the initial manifestations of myoclonic encephalopathy associated with neuroblastoma

Cerebellar ataxia and opsoclonus were the initial manifestations of an associated neuroblastoma in a 20-month-old girl. Two months after the initial symptomatology, a physical examination revealed an abnormal mass palpable left to the midline. Urinary catecholamines were within normal limits. The child's neurological findings improved immediately after surgery, and steroid treatment and the follow-up on her after 2 years revealed normal general and neurological development. The syndrome of myoclonic encephalopathy including cerebellar ataxia, myoclonus and opsoclonus, and its relationship to neuroblastoma is reviewed. Failure to recognize this association can result in delays in both diagnosis and treatment and could be fatal.

Saccade abnormalities in patients with ocular flutter

In a group of 8 patients with opsoclonus or ocular flutter, the eye movements were recorded by electro-oculography (EOG). The spontaneous eye movement pattern and the amplitude and peak velocity of the refixation saccade were analysed. The EOG recording demonstrated frequent bursts of horizontally and vertically directed saccades elicited without any intersaccadic interval. Three patients also demonstrated an increased frequency of square waves. In 6 of the 8 patients the peak velocity of the voluntary saccades was increased; in 5 patients this condition was found for saccades in both directions. Over-shooting oscillations or slightly hypermetric voluntary saccades occurred in 5 patients. It is proposed that the ocular flutter and the increased saccadic velocities found in the present series of patients is caused by a disorder of the burst cells in the brain stem saccadic control system.

Saccadic intrusions and oscillations

There are a number of different types of involuntary saccadic eye movements which differ from normal saccades in that they take the fovea away from its target. This article presents a classification and description of these abnormal eye movements and indicates how they may be used to increase the precision of neurologic diagnosis.