Opsoclonus Myoclonus Ataxia Syndrome Research Articles

Paraneoplastic opsoclonus-myoclonus syndrome as a rare presentation of parotid adenocarcinoma

Paraneoplastic Opsoclonus-Myoclonus Ataxia Syndrome (POMA) is a rare neurological condition that affects approximately 1 in 10,000,000 people annually. This syndrome is poorly understood and can lead to long-term cognitive, behavioral, and motor complications. Opsoclonus is characterized by involuntary, rapid, repetitive, multi-vectorial oscillations of the eyes occurring in all directions of gaze. It is accompanied by diffuse or focal body myoclonus and may or may not include ataxia and other cerebellar signs. POMA is typically a paraneoplastic syndrome associated with neuroblastoma in childhood and breast carcinoma or small-cell lung carcinoma in adults. Additionally, viral or toxic agents are known to play a role in its etiology, and the immune system is involved in the pathogenesis. We report a case of a 41-year-old man with anti-Ri antibody opsoclonus-myoclonus syndrome and parotid adenocarcinoma involvement. After diagnosing opsoclonus-myoclonus syndrome, the patient underwent multimodal immunotherapy treatment, resulting in partial remission of the neurological symptoms.

Late cognitive and adaptive outcomes of patients with neuroblastoma-associated opsoclonus-myoclonus-ataxia-syndrome: A report from the Children's Oncology Group.

Opsoclonus-myoclonus-ataxia syndrome (OMAS) is a rare autoimmune disorder of the nervous system presenting with abnormal eye and limb movements, altered gait, and increased irritability. Two to four percent of children diagnosed with neuroblastoma have neuroblastoma-associated OMAS (NA-OMAS). These children typically present with non-high-risk neuroblastoma that is cured with surgery, with or without chemotherapy. Despite excellent overall survival, patients with NA-OMAS can have significant persistent neurological and developmental issues. This study aimed to describe long-term neurocognitive and adaptive functioning of patients with NA-OMAS treated with multimodal therapy, including intravenous immunoglobulin (IVIG) on Children's Oncology Group (COG) protocol ANBL00P3. Of 53 children enrolled on ANBL00P3, 25 submitted evaluable neurocognitive data at diagnosis and at least one additional time point within 2years and were included in the analyses. Adaptive development was assessed via the Vineland Adaptive Behavior Scale, and validated, age-appropriate measures of intellectual function were also administered. Twenty-one of the 25 patients in this cohort ultimately received IVIG. Descriptive spaghetti plots suggest that this cohort demonstrated stable long-term cognitive functioning and adaptive development over time. This cohort also demonstrated decreased OMAS scores over time consistent with improved OMAS symptoms. While statistical significance is limited by small sample size and loss to follow-up over 10years, findings suggest stable long-term cognitive and adaptive functioning over time in this treated cohort.

Diagnostic value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography imaging in pediatric opsoclonus myoclonus ataxia syndrome presenting with neuroblastoma.

Early precision diagnosis and effective treatment of opsoclonus myoclonus ataxia syndrome (OMAS) patients presenting with neuroblastoma can prevent serious neurological outcomes. To assess the diagnostic value of 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging in pediatric OMAS with neuroblastoma. A retrospective evaluation of 45 patients diagnosed with OMAS who underwent 18F-FDG PET/CT was performed. A univariate analysis was performed to compare clinical characteristics between OMAS with and without neuroblastoma. Univariate and multivariate logistic regression analyses were applied to identify independent risk factors for OMAS with neuroblastoma and to develop the clinical model. Finally, independent risk factors and PET/CT were fitted to build the combined model for the diagnosis of OMAS with neuroblastoma and presented as a nomogram. Receiver operating characteristic curve, decision curve, and calibration curveanalyses were conducted to evaluate the performance of the models. Among 45 patients, 27 were PET/CT-positive, 23/27 lesions were neuroblastoma, and four were false positives. One of the false positive patients was confirmed to be adrenal reactive hyperplasia by postoperative pathology, and the symptoms of OMAS disappeared in the remaining three cases during clinical follow-up. The average maximal standardized uptake value of PET/CT-positive lesions was 2.6. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of PET/CT were 100%, 81.8%, 85.2%, 100%, and 91.1%, respectively. Age at diagnosis, lactate dehydrogenase, and neuron-specific enolase showed statistically significant differences between OMAS with and without neuroblastoma. Lactate dehydrogenase was identified as the independent risk factor to develop the clinical model, and the clinical model demonstrated an area under the curve (AUC) of 0.82 for the diagnosis of OMAS with neuroblastoma, with an AUC as high as 0.91 when combined with PET/CT. The decision curve analysis and calibration curve demonstrated that the nomogram had good consistency and clinical usefulness. In patients with OMAS, 18F-FDG PET/CT has a high diagnostic accuracy in detecting tumors of the neuroblastoma, especially when combined with the independent risk factor serum lactate dehydrogenase.

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

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

Review of Opsoclonus-Myoclonus Ataxia Syndrome in Pediatric Patients.

Opsoclonus-myoclonus ataxia syndrome (OMAS), also known as Kinsbourne syndrome, is a rare disorder that presents with myoclonus, ataxia, abnormal eye movements, irritability, and sleep disruptions, often in young children. We report a case of an infant barely 6 months old, with no significant past medical history, who presented to the emergency department with tremors, jerking motions of the head and arms, and rapid eye movements. After an extensive workup, she was found to have a neuroblastoma, which was subsequently surgically removed via thoracotomy. Despite an initial improvement in symptoms post-resection, the patient's symptoms recurred. She was subsequently treated with dexamethasone, intravenous immunoglobulin (IVIG), and rituximab. After treatment, the patient was noted to have mild global developmental delays but was otherwise well. This case report highlights the rare occurrence of OMAS in an infant barely 6 months old at diagnosis. Using the PubMed database, a systematic review was conducted to highlight the clinical presentation, diagnosis, and management of OMAS.

Clinical and prognostic analysis of opsoclonus-myoclonus-ataxia syndrome in children

Objective: To summarize the clinical and prognostic features of children with opsoclonus-myoclonus-ataxia syndrome (OMAS). Methods: A total of 46 patients who met the diagnostic criteria of OMAS in the Department of Neurology, Beijing Children's Hospital from June 2015 to June 2023 were retrospectively analyzed. Centralized online consultations or telephone visits were conducted between June and August 2023. The data of the children during hospitalization and follow-up were collected, including clinical manifestations, assistant examination, treatment and prognosis. According to the presence or absence of tumor, the patients were divided into two groups. The chi-square test or Mann-Whitney U test was used to compare the differences between the two groups. Univariate Logistic regression was used to analyze the factors related to OMAS recurrence and prognosis. Results: There were 46 patients, with 25 males and the onset age of 1.5 (1.2, 2.4) years. Twenty-six (57%) patients were diagnosed with neuroblastoma during the course of the disease, and no patients were categorized into the high-risk group. A total of 36 patients (78%) were followed up for≥6 months, and all of them were treated with first-line therapy with glucocorticoids, gammaglobulin and (or) adrenocorticotrophic hormone. Among the 36 patients, 9 patients (25%) were treated with second-line therapy for ≥3 months, including rituximab or cyclophosphamide, and 17 patients (47%) received chemotherapy related to neuroblastoma. At the follow-up time of 4.2 (2.2, 5.5) years, 10 patients (28%) had relapsed of OMAS. The Mitchell and Pike OMS rating scale score at the final follow-up was 0.5 (0, 2.0). Seven patients (19%) were mildly cognitively behind their peers and 6 patients (17%) were severely behind. Only 1 patient had tumor recurrence during follow-up. The history of vaccination or infection before onset was more common in the non-tumor group than in the tumor group (55%(11/20) vs. 23%(6/26), χ²=4.95, P=0.026). Myoclonus occurred more frequently in the non-tumor group (40%(8/20) vs. 4%(1/26), χ²=7.23, P=0.007) as the onset symptom. Univariate Logistic regression analysis showed that the tumor group had less recurrence (OR=0.19 (0.04-0.93), P=0.041). The use of second-line therapy or chemotherapy within 6 months of the disease course had a better prognosis (OR=11.64 (1.27-106.72), P=0.030). Conclusions: OMAS in children mostly starts in early childhood, and about half are combined with neuroblastoma. Neuroblastoma in combination with OMAS usually has a low risk classification and good prognosis. When comparing patients with OMAS with and without tumors, the latter have a more common infection or vaccination triggers, and myoclonus, as the onset symptom, is more common. Early addition of second-line therapy is associated with better prognosis in OMAS.

The case of Kinsburn’s Encephalopathy in a child with neuroblastoma of posterior mediastinum

Opsoclonus-myoclonus-ataxia syndrome (OMAS) is an autoimmune rare disease of the central nervous system with lesion of the cerebellum and its ligaments. Purpose - to present a case of the rare Kinsburn’s Encephalopathy - OMAS and to attract the attention to its timely diagnosis. Clinical case. A child at the age of 1 year and 9 months was observed in the neurological department of the National Children’s Specialized Hospital “OKHMATDYT”. Neurological status: eyes opsoclonus, truncal tremor, ataxia of the cerebellum. There were also changes in behavior and a sleep disorder. She became sick in 1 month after acute respiratory infection. True diagnosis was made: Kinsburn’s Encephalopathy - opsoclonus-myoclonus syndrome. A study of the child’s immune status was made and, most importantly, computerized tomography (CT) of the whole body. Mediastinal neuroblastoma was diagnosed. In addition to the diagnosis, the child receive adequate therapy - intravenous immunoglobulin at a dose of 2 g/kg for a 5-day course. On the background of the received therapy, the child was marked with positive dynamics, she began to walk by herself, the atactic syndrome diminished, opsoclonus remained unchanged. Consequently, the main cause of autoimmune defeat of the nervous system was detected and the child was directed to the further examination and treatment to the Cancer Institute of the National Academy of Medical Science of Ukraine. Radical removal of the left hemopleura neuroblastoma was made. According to the results of morphological and immunohistochemistry tests, the phenotype obtained in the material of the operation is characteristic of the neuroblastoma (ICD-O code 9500/3), pT1bpN0M0, negative form. In the future, the child continued to receive courses of immunosuppressive therapy. The research was carried out in accordance with the principles of the Helsinki Declaration. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Successful use of tacrolimus for treatment-refractory neuroblastoma-associated opsoclonus-myoclonus-ataxia syndrome: A case series.

Opsoclonus-myoclonus-ataxia syndrome (OMAS) is an autoimmune central nervous system disorder, primarily manifesting as a paraneoplastic sequalae to neuroblastoma, and characterized by motor disorders and behavioral disturbances. OMAS is typified by aberrant B-cell and T-cell activation. Current treatment involves immunosuppression using corticosteroids, intravenous immunoglobulin, and rituximab. However, these approaches often lead to treatment-related toxicities and symptomatic recurrences with chronic neurocognitive impairment. We treated three children with refractory neuroblastoma-associated OMAS with tacrolimus, a T-cell-targeting calcineurin inhibitor, effectively controlling symptoms within a month and enabling the discontinuation of immunosuppression with minimal side effects. Tacrolimus shows promise as a therapeutic option for refractory OMAS.

A rare case report of COVID-19 related recurrent opsoclonus myoclonus ataxia syndrome (OMS)

A rare case report of COVID-19 related recurrent opsoclonus myoclonus ataxia syndrome (OMS)

Parainfectious opsoclonus myoclonus ataxia syndrome in adults: A case series and literature review

Parainfectious opsoclonus myoclonus ataxia syndrome in adults: A case series and literature review

Opsoclonus-Myoclonus-Ataxia Syndrome Due to Covid-19.

Opsoclonus-myoclonus syndrome (OMS) as a rare neurological encephalopathic entity associated with non-specific infections or cancer processes has been repeatedly described in the setting of SARS-CoV-2 infection. We report a case of a 53-year-old man with SARS-CoV-2 infection, who developed clinical features of opsoclonus-myoclonus ataxia syndrome including cognitive impairments with a prolonged course of disease. Of particular note, cerebrospinal fluid (CSF) analysis revealed the production of myelin oligodendrocyte glycoprotein (MOG) antibodies, suggesting an underlying neuroimmunological mechanism associated with infection with the novel SARS-CoV-2 virus.

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.

Polyclonal lymphoid expansion drives paraneoplastic autoimmunity in neuroblastoma

Neuroblastoma is a lethal childhood solid tumor of developing peripheral nerves. Two percent of children with neuroblastoma develop opsoclonus myoclonus ataxia syndrome (OMAS), a paraneoplastic disease characterized by cerebellar and brainstem-directed autoimmunity but typically with outstanding cancer-related outcomes. We compared tumor transcriptomes and tumor-infiltrating T and B cell repertoires from 38 OMAS subjects with neuroblastoma to 26 non-OMAS-associated neuroblastomas. We found greater B and Tcell infiltration in OMAS-associated tumors compared to controls and showed that both were polyclonal expansions. Tertiary lymphoid structures (TLSs) were enriched in OMAS-associated tumors. We identified significant enrichment of the major histocompatibility complex (MHC) class II allele HLA-DOB∗01:01 in OMAS patients. OMAS severity scores were associated with the expression of several candidate autoimmune genes. We propose a model in which polyclonal auto-reactive B lymphocytes act as antigen-presenting cells and drive TLS formation, thereby supporting both sustained polyclonal Tcell-mediated anti-tumor immunity and paraneoplastic OMAS neuropathology.

Retrospective analysis of COVID-19patients with Guillain-Barre, Miller-Fisher, and opsoclonus-myoclonus-ataxia syndromes-acase series.

In accordance with the rising number of SARS-CoV‑2 infections, reports of neurological complications have also increased. They include cerebrovascular diseases but also immunological diseases such as Guillain-Barre syndrome (GBS), Miller-Fisher syndrome (MFS), and opsoclonus-myoclonus-ataxia syndrome (OMAS). While GBS and MFS are typical postinfectious complications, OMAS has only recently been described in the context of COVID-19. GBS, MFS, and OMAS can occur as para- and postinfectious, with different underlying pathomechanisms depending on the time of neurological symptom onset. The study aimed to describe clinical features, time between infection and onset of neurological symptoms, and outcome for these diseases. All COVID-19patients treated in the neurological ward between January 2020 and December 2022 were screened for GBS, MFS, and OMAS. The clinical features of all patients, with aparticular focus on the time of onset of neurological symptoms, were analyzed. This case series included 12 patients (7GBS, 2MFS, 3OMAS). All GBS and one MFS patient received immunomodulatory treatment. Three patients (2GBS, 1OMAS) had asevere COVID-19 infection and received mechanical ventilation. In patients with OMAS, only one patient received treatment with intravenous immunoglobulin and cortisone. The remaining two patients, both with disease onset concurrent with SARS-COV‑2 infection, recovered swiftly without treatment. In all subgroups, patients with concurrent onset of neurological symptoms and COVID-19 infection showed atrend toward shorter disease duration. All patient groups displayed ashorter disease duration if the onset of neurological symptoms occurred shortly after the COVID-19 diagnosis. In particular, both the OMAS patients with symptom onset concurrent with COVID-19 showed only abortive symptoms followed by aswift recovery. This observation would suggest different pathomechanisms for immune-mediated diseases depending on the time of onset after an infection.

Pediatric opsoclonus myoclonus ataxia syndrome in the setting of COVID-19 (P5-9.010)

<h3>Objective:</h3> To describe peri-infectious opsoclonus myoclonus ataxia syndrome (OMAS) in the setting of COVID-19 infection in children. <h3>Background:</h3> OMAS is well described in pediatric patients with peripheral neuroblastic tumors and less defined in the setting of peri-infectious etiologies such as SARS-CoV-19 which is better appreciated in adults. <h3>Design/Methods:</h3> We describe two separate cases of peri-infectious COVID-19 OMAS in pediatric patients at a tertiary Children’s Hospital in 2022, both previously healthy female patients, 2 years and 18 months of age. <h3>Results:</h3> Patient A is a two year-old female who initially presented with ataxia in context of acute COVID-19 infection at 16 months of age and later developed abnormal eye movements, myoclonus and irritability with multiple relapses over a nine month period. Patient B is a 18 month-old female presenting with acute onset abnormal eye movements and ataxia at age 14 months and later developed myoclonic jerks and irritability with sleep disturbance, subsequently found to have COVID-19 antibodies, now with remission of symptoms. Both patients had comprehensive work up for malignancy, toxic-metabolic encephalopathy, structural central nervous system disease, infectious meningoencephalitis and genetic ataxia syndromes. Both were treated with IVIG and high dose steroids. Patient A had subsequent relapses and required escalation of treatment to ACTH. Patient A had a more complicated course which included treatment with acetazolamide and levetiracetam for myoclonus. Her myoclonic jerks demonstrated intermittent electrographic correlates on EEG. <h3>Conclusions:</h3> While OMAS associated with neuroblastic tumors is well described in the pediatric literature, it is less well known in relation to peri-infectious phenomena, particularly SARS-CoV-2 infection in children. Prior published reports of OMAS related to COVID-19 infection in adults indicated a favorable prognosis after initial treatment. However, we present a case with repeated relapses and the need for more aggressive treatment. The present report broadens the phenotypic spectrum for OMAS outside of paraneoplastic etiologies. <b>Disclosure:</b> Dr. Yakir has nothing to disclose. Dr. Most has nothing to disclose. Dr. Hermel has nothing to disclose. Dr. Zimbric has received personal compensation in the range of $0-$499 for serving as a Survey volunteer with Opinionsite. An immediate family member of Dr. Friedman has received personal compensation in the range of $0-$499 for serving as a Consultant for Sinopia Biosciences. An immediate family member of Dr. Friedman has received personal compensation in the range of $0-$499 for serving as an officer or member of the Board of Directors for Pet Dx. Dr. Friedman has received personal compensation in the range of $0-$499 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for MedLink Neurology. Dr. Friedman has stock in Friedman Bioventure . Dr. Rho has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Eisai. Dr. Rho has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Nutricia. Dr. Rho has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Cerecin. Dr. Rho has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Mallinckrodt. Dr. Rho has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Biocodex. Dr. Rho has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Zogenix. Dr. Rho has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for Aquestive. The institution of Dr. Rho has received research support from National Institutes of Health. Dr. Rho has received publishing royalties from a publication relating to health care.

A Case of Dancing Eyes and Feet (P4-5.006)

<h3>Objective:</h3> To present a case of opsoclonus-myoclonus-ataxia syndrome in an adult patient following Epstein Barr Virus infection. <h3>Background:</h3> Opsoclonus-myoclonus-ataxia syndrome (OMAS), also called disorder of dancing eyes and feet, is a condition that causes opsoclonus along with diffuse or focal body myoclonus and truncal titubation with or without ataxia and other cerebellar signs. It is commonly seen as a paraneoplastic syndrome in children with neuroblastoma; however, there are several associated post-infectious and paraneoplastic etiologies in children and adults. <h3>Design/Methods:</h3> NA <h3>Results:</h3> A 26-year-old woman developed generalized malaise, abdominal discomfort, and right upper quadrant abdominal swelling. One week later, she developed blurred vision and gait impairment, for which she presented to the emergency room. On physical exam, she had opsoclonus, left appendicular ataxia, and left hemi-ataxic gait. Brain magnetic resonance imaging was normal. Serologic studies revealed elevated liver function tests and positive Epstein Barr Virus (EBV) IgM and IgG. Evaluation of cerebrospinal fluid revealed normal cells, glucose, and protein, negative oligoclonal bands as well as negative meningitis/encephalitis polymerase chain reaction panel and negative autoimmune encephalopathy panel. Workup for occult neoplasms was unrevealing. She was diagnosed with post-infectious OMAS due to EBV. She was treated with high-dose steroids with taper and intravenous immunoglobulin, which led to further improvement. Gabapentin, clonazepam, and topiramate were used for symptomatic treatment of opsoclonus. <h3>Conclusions:</h3> We describe clinical features, diagnostic workup, and treatment of a case of Epstein Barr Virus-associated post-infectious opsoclonus-myoclonus-ataxia syndrome in an adult. Despite recovery from the viral illness, the patient continued to have symptoms for several weeks which were ultimately improved with steroids and IVIG. <b>Disclosure:</b> Dr. Ahden has nothing to disclose. Dr. George has nothing to disclose. Dr. Samkoff has nothing to disclose.

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

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. 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. 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. 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.

Opsoclonus-myoclonus-ataxia syndrome as a complication of pembrolizumab treatment in an adult patient (a case report and literature review)

Background. Opsoclonus-myoclonus-ataxia syndrome (OMAS) in adults is an extremely rare condition, often leading to rapidly deteriorated neurological performance. The majority of published cases are considered as being of post-infectious, paraneoplastic or idiopathic origin. However, there have been reported few OMAS cases developed after administration of check-point inhibitors used in various oncological conditions. In the last decade, the widespread use of immunotherapy in oncology has led to rise in immune-related adverse events, including diverse neurological toxicities.Objective: to evaluate an opportunity of OMAS-triggering PD-1 treatment.Material and methods. We present the case report of a subacute OMAS onset in an elderly man after continuous administration of pembrolizumab as a first line treatment in bronchial squamous cell carcinoma. The study was conducted in accordance with the Helsinki Declaration. We also review the main OMAS clinical features, pathogenesis and immunological mechanisms in adults along with potential diagnostic and management strategies.Results. The development of severe OMAS clinical picture during immunotherapy required the withdrawal of targeted treatment, which in combination with glucocorticoids led to a prominent regression of neurological deficit. After a thorough clinical investigation, infectious and organic factors were excluded, allowing for proposal of immunotherapy-triggered OMAS etiology in the patient.Conclusion. Discontinuation of immunotherapy may be a justified means for OMAS clinical features in adult patients with verified oncological condition undergoing treatment with check-point inhibitors (considering all other etiologies are ruled out).

Neuroblastic Tumor Recurrence Associated With Opsoclonus Myoclonus Ataxia Syndrome Relapse a Decade After Initial Resection and Treatments.

Opsoclonus myoclonus ataxia syndrome (OMAS) is a rare disorder that causes significant neurodevelopmental sequelae in children. Approximately half of pediatric OMAS cases are paraneoplastic, typically associated with localized neuroblastic tumors. Since early persistence or relapse of OMAS symptoms is common even after tumor resection, OMAS relapses may not routinely prompt reevaluation for recurrent tumors. We report a 12-year-old girl with neuroblastic tumor recurrence associated with OMAS relapse a decade after initial treatment. Providers should be aware of tumor recurrence as a trigger for distant OMAS relapse, raising intriguing questions about the role of immune surveillance and control of neuroblastic tumors.

Neuroblastoma with opsoclonus myoclonus ataxia syndrome - Case series from tertiary care center

Neuroblastoma with opsoclonus myoclonus ataxia syndrome - Case series from tertiary care center