High dose pulsatile dexamethasone therapy in children with opsoclonus-myoclonus syndrome

Sarcopenia in Children with Solid Organ Tumors: An Instrumental Era

Sarcopenia has recently been studied in both adults and children and was found to be a prognostic marker for adverse outcome in a variety of patient groups. Our research showed that sarcopenia is a relevant marker in predicting outcome in children with solid organ tumors, such as hepatoblastoma and neuroblastoma. This was especially true in very ill, high-risk groups. Children with cancer have a higher likelihood of ongoing loss of skeletal muscle mass due to a mismatch in energy intake and expenditure. Additionally, the effects of cancer therapy, hormonal alterations, chronic inflammation, multi-organ dysfunction, and a hypermetabolic state all contribute to a loss of skeletal muscle mass. Sarcopenia seems to be able to pinpoint this waste to a high degree in a new and objective way, making it an additional tool in predicting and improving outcome in children. This article focuses on the current state of sarcopenia in children with solid organ tumors. It details the pathophysiological mechanisms behind sarcopenia, highlighting the technical features of the available methods for measuring muscle mass, strength, and function, including artificial intelligence (AI)-based techniques. It also reviews the latest research on sarcopenia in children, focusing on children with solid organ tumors.

[Virus-induced opsoclonus-myoclonus syndrome during pregnancy]

Opsoclonus-myoclonus syndrome (OMS) is a very rare condition with various etiologies (paraneoplastic, parainfectious, toxic, idiopathic, etc.) with an autoimmune pathogenetic mechanism of development. The authors describe the case of OMS in a 41-year-old woman at 37 weeks of gestation, who developed opsoclonus, myoclonus, severe trunk ataxia, tremor and bilateral pyramidal symptoms, inability to sit, stand and walk without support. Differential diagnosis was conducted between virus-induced OMS, rotavirus encephalitis, paraneoplastic syndrome, and demyelinating diseases of the central nervous system. Routine laboratory tests of blood and urine, serological tests of blood and cerebrospinal fluid (CSF) revealed no pathology. Only small lymphocytic pleocytosis and a slight increase in protein were observed in CSF. No pathology was detected during magnetic resonance imaging. On the 40th week of pregnancy (20th day of illness), the patient gave birth to a healthy full-term baby through the birth canal. In view of the most likely autoimmune process triggered by rotavirus infection, intravenous immunosuppressive therapy with methylprednisolone (1000 mg/day №3) was performed, followed by switching to prednisolone per os (60 mg/kg/day), as well as neuroprotective and neurometabolic therapy with cytoflavin. On day 42 of the illness (and on day 20 of the immunosuppressive therapy), a significant positive trend was noted. The patient was discharged on day 56 with light residual elements of opsoclonus and ataxia, and could walk independently without support. Thus, in case of suspected OMS, it is necessary to conduct a mandatory full diagnostic search, especially aimed at exclusion of the paraneoplastic process. And also, given the possibility of recurrence, further outpatient monitoring of these patients should be carried out.

Update on opsoclonus-myoclonus syndrome in adults

Opsoclonus-myoclonus syndrome in adults is a rare and heterogeneous disorder with the clinical features of opsoclonus, myoclonus, ataxia, and behavioral and sleep disturbances. The pathophysiology is thought to be immunological on the basis of paraneoplastic or infectious etiologies. Immunomodulatory therapies should be performed although the response may be incomplete. A number of autoantibodies have been identified against a variety of antigens, but no diagnostic immunological marker has yet been identified. This review focuses on underlying mechanisms of opsoclonus-myoclonus syndrome, including findings that have been identified recently, and provides an update on the clinical features and treatments of this condition.

Demographic, Clinical, and Immunologic Features of 389 Children with Opsoclonus-Myoclonus Syndrome: A Cross-sectional Study

Pediatric-onset opsoclonus-myoclonus syndrome (OMS) is a devastating neuroinflammatory, often paraneoplastic, disorder. The objective was to characterize demographic, clinical, and immunologic aspects in the largest cohort reported to date. Cross-sectional data were collected on 389 children in an IRB-approved, observational study at the National Pediatric Myoclonus Center. Non-parametric statistical analysis was used. OMS manifested in major racial/ethnic groups, paralleling US population densities. Median onset age was 1.5 years (1.2–2 interquartile range), inclusive of infants (14%), toddlers (61%), and youngsters (25%). The higher female sex ratio of 1.2 was already evident in toddlers. Time to diagnosis was 1.2 months (0.7–3); to treatment, 1.4 months (0.4–4). Irritability/crying dominated prodromal symptomatology (60%); overt infections in <35%. Acute cerebellar ataxia was the most common misdiagnosis; staggering appeared earliest among 10 ranked neurological signs (P < 0.0001). Some untreated youngsters had no words (33%) or sentences (73%). Remote neuroblastic tumors were detected in 50%; resection was insufficient OMS treatment (58%). Age at tumor diagnosis related to tumor type (P = 0.004) and stage (P = 0.002). A novel observation was that paraneoplastic frequency varied with patient age—not a mere function of the frequency of neuroblastoma, which was lowest in the first 6 months of life, when that of neuroblastoma without OMS was highest. The cerebrospinal fluid (CSF) leukocyte count was minimally elevated in 14% (≤11/mm³) with normal differential, and commercially screened serum autoantibodies were negative, but CSF oligoclonal bands (OCB) and B cells frequency were positive (58 and 93%). Analysis of patients presenting on immunotherapy revealed a shift in physician treatment practice patterns from monotherapy toward multi-agent immunotherapy (P < 0.001); the number of agents/sequences varied. In sum, a major clinical challenge is to increase OMS recognition, prevent initial misdiagnosis, and shorten time to diagnosis/treatment. The index of suspicion for an underlying tumor must remain high despite symptoms of infection. The disparity in onset age of neuroblastoma frequency with that of neuroblastoma with OMS warrants further studies of potential host/tumor factors. OMS neuroinflammation is best diagnosed by CSF OCB and B cells, not by routine CSF or commercial antibody studies.

Clinical Management of Pediatric Acute-Onset Neuropsychiatric Syndrome: Part II-Use of Immunomodulatory Therapies

Introduction: Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) is a clinically heterogeneous disorder with a number of different etiologies and disease mechanisms. Inflammatory and postinfectious autoimmune presentations of PANS occur frequently, with some clinical series documenting immune abnormalities in 75%-80% of patients. Thus, comprehensive treatment protocols must include immunological interventions, but their use should be reserved only for PANS cases in which the symptoms represent underlying neuroinflammation or postinfectious autoimmunity, as seen in the PANDAS subgroup (Pediatric Autoimmune Neuropsychiatric Disorders associated with Streptococcal infections). Methods: The PANS Research Consortium (PRC) immunomodulatory task force is comprised of immunologists, rheumatologists, neurologists, infectious disease experts, general pediatricians, psychiatrists, nurse practitioners, and basic scientists with expertise in neuroimmunology and PANS-related animal models. Preliminary treatment guidelines were created in the Spring of 2014 at the National Institute of Health and refined over the ensuing 2 years over conference calls and a shared web-based document. Seven pediatric mental health practitioners, with expertise in diagnosing and monitoring patients with PANS, were consulted to create categories in disease severity and critically review final recommendations. All authors played a role in creating these guidelines. The views of all authors were incorporated and all authors gave final approval of these guidelines. Results: Separate guidelines were created for the use of immunomodulatory therapies in PANS patients with (1) mild, (2) moderate-to-severe, and (3) extreme/life-threatening severity. For mildly impairing PANS, the most appropriate therapy may be "tincture of time" combined with cognitive behavioral therapy and other supportive therapies. If symptoms persist, nonsteroidal anti-inflammatory drugs and/or short oral corticosteroid bursts are recommended. For moderate-to-severe PANS, oral or intravenous corticosteroids may be sufficient. However, intravenous immunoglobulin (IVIG) is often the preferred treatment for these patients by most PRC members. For more severe or chronic presentations, prolonged corticosteroid courses (with taper) or repeated high-dose corticosteroids may be indicated. For PANS with extreme and life-threatening impairment, therapeutic plasma exchange is the first-line therapy given either alone or in combination with IVIG, high-dose intravenous corticosteroids, and/or rituximab. Conclusions: These recommendations will help guide the use of anti-inflammatory and immunomodulatory therapy in the treatment of PANS.

Dexamethasone, Intravenous Immunoglobulin, and Rituximab Combination Immunotherapy for Pediatric Opsoclonus-Myoclonus Syndrome

BACKGROUND

Although pulse-dose dexamethasone is increasingly favored for treating pediatric opsoclonus-myoclonus syndrome (OMS), and multimodal immunotherapy is associated with improved clinical response, there have been no neuroimmunologic studies of dexamethasone-based multimodal disease-modifying therapy.

METHODS

In this observational retrospective study, 19 children with OMS (with or without associated neuroblastoma) underwent multibiomarker evaluation for neuroinflammation. Nine children of varying OMS severity, duration, and treatment status were treated empirically with pulse dexamethasone, intravenous immunoglobulin (IVIg), and rituximab combination immunotherapy (DEXIR-CI). Another 10 children on dexamethasone alone or with IVIg at initial evaluation only provided a comparison group. Motor severity (total score) was scored rater-blinded via videotapes using the validated OMS Evaluation Scale.

RESULTS

DEXIR-CI was associated with a 69% reduction in group total score (P = 0.004) and was clinically well tolerated. Patients given the dexamethasone combination exhibited significantly lowered B cell frequencies in cerebrospinal fluid (-94%) and blood (-76%), normalizing the cerebrospinal fluid B cell percentage. The number of patients with positive inflammatory markers dropped 87% (P = 0.002) as did the number of markers. Cerebrospinal fluid oligoclonal bands were positive in four of nine pretreatment patients but zero of six post-treatment patients. In the comparison group, partial response to dexamethasone alone or with IVIg was associated with multiple positive markers for neuroinflammation despite an average of seven months of treatment.

CONCLUSIONS

Multimechanistic dexamethasone-based combination immunotherapy increases the therapeutic armamentarium for OMS, providing a viable option for less severely affected individuals. Partial response to dexamethasone with or without IVIg is indicative of ongoing neuroinflammation and should be treated promptly and accordingly.

Cancer and Autoimmunity: Paraneoplastic Neurological Disorders Associated With Neuroblastic Tumors

Cancer and autoimmunity come together in paraneoplastic syndromes (PNS), which reflect the remote, not direct, effects of cancer. In the pediatric population, a variety of PNS have been described, but the most common of these rare disorders are instigated by neuroblastic tumors, such as neuroblastoma, ganglioneuroblastoma, and ganglioneuroma. The main pediatric-onset neurological PNS are ROHHAD syndrome, anti-ANNA1 (anti-Hu), and opsoclonus-myoclonus syndrome. They manifest distinctive neurological features, which aid the diagnosis, though under-recognition still poses serious challenges and risks. In each clinical syndrome, a large subgroup of patients had no demonstrated tumor. Most neurological PNS are immunologically mediated, and CSF neuroimmunological studies show common elements of immune involvement in PNS as well as important differences. Future immunotherapy strategies may be able to take advantage of these abnormalities.

Neurological Complications of Pediatric Cancer

Neurologists are often consulted for diagnosis and management of neurologic complications in patients undergoing therapy for cancer. Pediatric patients with cancer, often undergoing the same types of therapy as adults with cancer, may experience different adverse events. The set of neurologic complications in children differs from that in adults and the neurologist must take into account the continuing growth and development of the patient as well as significant differences in primary diagnosis across the population. Correctly recognizing complications and initiating prompt treatment may reduce pain and prevent further progression and permanent deficits. Herein, we review the most recent literature on the neurological complications of cancer therapy organized by frequency in the pediatric population.

Opsoclonus-myoclonus syndrome after adenovirus infection

Autoimmune and paraneoplastic movement disorders are rare in childhood. Diagnosis often relies on clinical manifestations and clinicians' recognition. A 22-month-old girl at onset of opsoclonus-myoclonus syndrome (OMS) was followed for 8 years. Adenovirus (type C subtype 3) infection coincided with manifestation. Data on treatment, imaging and follow-up are provided. In the spinal fluid, elevated anti-rubella antibodies and oligoclonal bands were detected. An autoimmune process affecting mainly cerebellar neurons was revealed immunohistochemically. Moderately intense long-term immunosuppressive therapy resulted in a favorable clinical outcome. A video demonstrated severe OMS manifestations at onset, followed by nearly complete recovery after treatment. We describe the association of a parainfectious OMS and adenovirus infection; laboratory results indicate a non-specific humoral process affecting mainly cerebellar neurons. Our video documentation will aid to recognize this rare movement disorder and to initiate early treatment.

Effect of Increased Immunosuppression on Developmental Outcome of Opsoclonus Myoclonus Syndrome (OMS)

Opsoclonus myoclonus syndrome (OMS) produces long-term cognitive, behavioral, and motor deficits. Objective was to see if more aggressive treatment improved outcome. Assessment included opsoclonus myoclonus syndrome rating, developmental/cognitive and motor assessment, and adaptive behavior. Fourteen subjects completed testing. Nine had neuroblastoma. Onset was at 10 to 35 months; onset to diagnosis: 2 days to 14 months, and onset to first treatment: 5 days to 15 months. Initial treatment was corticotropin (12), oral steroids (3), plus intravenous immunoglobulin in all. Ten received rituximab, 5 cyclophosphamide. Age at testing ranged from 2.5 to 10.3 years. Adaptive Behavior Score (11 subjects), mean 93.5; estimated Intelligence Quotient/Developmental Quotient mean 93.5; Motor: mean 92.8. Residual opsoclonus myoclonus syndrome symptoms at the time of the evaluation were generally minor; opsoclonus myoclonus syndrome scores ranged from 0 to 6. Comparison to previously reported opsoclonus myoclonus syndrome subjects showed improved outcomes: Adaptive behavior, cognitive and motor scores were significantly higher (P < .001) in new subjects. Outcomes have improved with more aggressive immunosuppression, with most opsoclonus myoclonus syndrome survivors now functioning at or near normal.

Another promising treatment option for neuroblastoma-associated opsoclonus-myoclonus syndrome by oral high-dose dexamethasone pulse: lymphocyte markers as disease activity

A one-year-old boy with neuroblastoma (NBoma)-associated opsoclonus-myoclonus syndrome (OMS) was treated by oral high-dose dexamethasone (DEX) pulses (20 mg/m(2)/day of DEX for three consecutive days) every 28 days for 6 months after resection of the tumor. All OMS symptoms improved after the first course of DEX pulse therapy and disappeared after the last course. No adverse effects were observed. Minor deterioration of his developmental quotient was noted 33 months after the onset of the disease. NBoma remission has been maintained since treatment. Before DEX pulse therapy, frequency of T lymphocyte, in particular CD4-positive cell decreased markedly resulted in low CD4/8 ratio in the peripheral blood (PB). The frequency of B lymphocyte increased, especially in cerebrospinal fluid. These aberrant values in PB were reversed by DEX pulse therapy and correlated well with the neurological symptoms. A prospective study that assesses the efficacy of this promising and inexpensive treatment for OMS is warranted.

Movement disorder emergencies in childhood

The literature on paediatric acute-onset movement disorders is scattered. In a prospective cohort of 52 children (21 male; age range 2mo-15y), the commonest were chorea, dystonia, tremor, myoclonus, and Parkinsonism in descending order of frequency. In this series of mainly previously well children with cryptogenic acute movement disorders, three groups were recognised: (1) Psychogenic disorders (n = 12), typically >10 years of age, more likely to be female and to have tremor and myoclonus (2) Inflammatory or autoimmune disorders (n = 22), including N-methyl-d-aspartate receptor encephalitis, opsoclonus-myoclonus, Sydenham chorea, systemic lupus erythematosus, acute necrotizing encephalopathy (which may be autosomal dominant), and other encephalitides and (3) Non-inflammatory disorders (n = 18), including drug-induced movement disorder, post-pump chorea, metabolic, e.g. glutaric aciduria, and vascular disease, e.g. moyamoya. Other important non-inflammatory movement disorders, typically seen in symptomatic children with underlying aetiologies such as trauma, severe cerebral palsy, epileptic encephalopathy, Down syndrome and Rett syndrome, include dystonic posturing secondary to gastro-oesophageal reflux (Sandifer syndrome) and Paroxysmal Autonomic Instability with Dystonia (PAID) or autonomic 'storming'. Status dystonicus may present in children with known extrapyramidal disorders, such as cerebral palsy or during changes in management e.g. introduction or withdrawal of neuroleptic drugs or failure of intrathecal baclofen infusion; the main risk in terms of mortality is renal failure from rhabdomyolysis. Although the evidence base is weak, as many of the inflammatory/autoimmune conditions are treatable with steroids, immunoglobulin, plasmapheresis, or cyclophosphamide, it is important to make an early diagnosis where possible. Outcome in survivors is variable. Using illustrative case histories, this review draws attention to the practical difficulties in diagnosis and management of this important group of patients.

Outcome and prognostic features in opsoclonus-myoclonus syndrome from infancy to adult life

OBJECTIVE

Opsoclonus-myoclonus syndrome (OMS) is a serious and often chronically disabling neurologic illness with onset in early childhood. Our aim was to identify long-term neurologic sequelae of OMS and predictors for disease outcome.

METHODS

We retrospectively assessed the case records of 101 patients diagnosed with OMS over a 53-year period. Clinical data were obtained from medical record review; we documented age at onset, severity of symptoms, response to treatment, and neurocognitive sequelae.

RESULTS

Overall, 21% of the patients had a neuroblastoma detected; however, in those born after 1990, this figure rose to 40%. Sixty-one percent of the patients had a chronic-relapsing course, 32% experienced several acute exacerbations, and 7% had a monophasic course. At the most recent review, 60% had residual motor problems, 66% speech abnormalities, 51% learning disability, and 46% behavior problems. One-third of the patients had normal intellectual outcome and cessation of symptoms. A severe initial presentation predicted a chronic disease course (odds ratio [OR]: 2.77 [95% confidence interval (CI): 1.47-5.23]; P = .002) and later learning disability (OR: 2.03 [95% CI: 1.08-3.79]; P = .026). Those with cognitive impairment were younger at disease onset (15.0 vs 19.5 months; P = .029). A chronic-relapsing disease course was associated with motor (P < .001), speech (P = .001), cognitive (P < .001), and behavior (P = .006) problems.

CONCLUSIONS

OMS is a chronic and debilitating illness; those with severe initial symptoms and those who are very young at disease onset are at increased risk of developing long-term sequelae. It is important for affected children to be identified early, because they might benefit from targeted immunomodulating therapy in specialist centers.

Update on diagnosis, treatment, and prognosis in opsoclonus-myoclonus-ataxia syndrome

PURPOSE OF REVIEW

Opsoclonus-myoclonus-ataxia syndrome (OMS) is a severe autoimmune central nervous system disorder, which predominantly affects young children and causes lifelong neurological disability. Early recognition and treatment may yield better outcomes.

RECENT FINDINGS

Appreciation of the spectrum of clinical presentations of OMS, awareness of common misdiagnoses, and utilization of diagnostic criteria may facilitate the timely diagnosis of OMS. Approximately 50% of patients have an associated neuroblastoma, which may escape detection by traditional methods and require MRI or computed tomography of the torso for diagnosis. In nonparaneoplastic cases, many associated infections have been reported. Although there has been progress in autoantibody identification and cerebrospinal fluid B cell expansion is a common finding, there is no diagnostic biomarker for OMS currently. Approximately 80% of reported patients, typically treated with conventional therapies such as adrenocorticotropin hormone, corticosteroids, and/or intravenous immunoglobulin, develop long-term neurological morbidity. Newer treatment approaches using early, aggressive therapy with cyclophosphamide or rituximab are promising.

SUMMARY

The diagnosis of OMS requires a high level of suspicion and a systematic approach for diagnostic testing, particularly for neuroblastoma. Future collaborative studies are required to determine whether early, aggressive therapy will improve the typically poor long-term neurological outcome.

Opsoclonus-myoclonus in children associated or not with neuroblastoma

OBJECTIVE

To compare the clinical data at diagnosis, treatment and neurological outcome in 34 children with opsoclonus-myoclonus syndrome (OMS) associated with a detected neuroblastoma or not.

STUDY DESIGN

This is a multicentric retrospective study of 34 children presenting with OMS from four pediatric centers diagnosed between 1988 and 2008.

RESULTS

Twenty-two patients had OMS associated with a neuroblastoma. These patients all had neuroblastomas with favourable prognostic features; all underwent surgery, six received chemotherapy. Twelve children had OMS without a detected neuroblastoma. For OMS, the main treatment in all children was corticotherapy (n=33), but immunoglobulins (n=13), cyclophosphamide (n=4) and rituximab (n=4) were also given. In the 27 OMS patients with or without neuroblastoma whose follow up was greater than two years, the neurological outcome was evaluated: 59.3% had neurological sequelae, including motor, praxic and/or language sequelae (n=9), persistent ataxia (n=6) and moderate motor deficit (n=3). No significant difference in neurological outcome was noted between the two patient groups.

CONCLUSION

Our retrospective study provides further evidence that OMS with or without a detected neuroblastoma is the same disease, whose major challenges are the neurological sequelae. An international collaboration is required to improve the knowledge about OMS, the treatment and the outcome in this rare disorder.

Adrenocorticotropic hormone versus pulsatile dexamethasone in the treatment of infantile epilepsy syndromes

For treatment of intractable epilepsies, there are no data comparing conventional adrenocorticotropic hormone and pulsatile corticoid therapy with dexamethasone. A retrospective comparison of efficacy was therefore conducted for both forms of application. Between 1989 and 2001, a series of 11 children with West syndrome and 3 with Lennox-Gastaut syndrome were treated with adrenocorticotropic hormone (group 1); between 2003 and 2006, 7 children with West syndrome, 5 with electrical status epilepticus during slow sleep, and 2 with Lennox-Gastaut syndrome were treated with pulsatile corticoid therapy (group 2). In group 1 (n = 14), 9/11 West syndrome patients became seizure free, but none with Lennox-Gastaut syndrome (0/3). In group 2 (n = 14), 4/7 West syndrome patients became seizure-free, 1/2 with Lennox-Gastaut syndrome exhibited seizure-frequency reduction, and 2/5 patients with electrical status epilepticus during slow-wave sleep exhibited significant improvement according to electroencephalograms. In West syndrome, pulsatile corticoid therapy was an effective alternative treatment to adrenocorticotropic hormone, whereas in Lennox-Gastaut syndrome in general steroids did not lead to a significant seizure reduction. In electrical status epilepticus during slow-wave sleep, treatment with pulsatile corticoid therapy seems to be effective and should be investigated in a larger group of patients.

Response to rituximab and prednisolone for opsoclonus-myoclonus-ataxia syndrome in a child with ganglioneuroblastoma

Opsoclonus-myoclonus-ataxia (OMA) syndrome is a rare neurobehavioral paraneoplastic disorder in children with neuroblastic tumors. The neurologic symptoms are generally treated with a number of immunosupressive and immunomodulating agents. A 4-year-old previously healthy male patient was admitted to the authors' center with progressive ataxia, gait disturbance, difficulty of speech, and opsoclonus. He had a diagnosis of ganglionueroblastoma at the thoracal paraspinal region. Following surgery, the patient received IVIG and prednisolone but his cerebellar symptoms progressed. Rituximab therapy was started and continued for total 8 weeks without any side effect. The authors observed excellent neurologic response in the patient at the 4th week of treatment. Rituximab is a new, promising, and safe therapy for OMA syndrome in children with neuroblastoma.

Emergency department presentation of a rare neurological disorder

The treatment and disposition of patients with neurological disorders is commonplace in the emergency setting, but atypical and uncommon presentations can prove to be especially challenging. In this article we discuss the case of a 31-year-old woman who presented with a rare disorder known as opsoclonus myoclonus syndrome (OMS). OMS is characterized by involuntary, multidirectional movement of the eyes, myoclonus, and truncal ataxia. The etiology is thought to be autoimmune, and is most commonly associated with encephalitis or paraneoplastic syndrome. After an 8-day hospital course, which included several different treatment modalities including plasmapheresis, the patient was discharged after making a complete recovery. Unusual presentations such as the one described in this article illustrate the point that it is crucial to have a systematic approach that can be applied to identify and treat potentially life-threatening neurological conditions.

Chronic relapsing opsoclonus-myoclonus syndrome: combination of cyclophosphamide and dexamethasone pulses

Opsoclonus-myoclonus syndrome (OMS) is a rare and debilitating disorder of unknown etiology affecting children and adults. Outcome is unfavourable; approximately 80% of children with OMS suffer from mild to severe neurological handicaps, mainly cognitive impairment. A standard therapy does not exist. Due to the possible immune-mediated mechanisms, treatment with steroids, ACTH, plasmapheresis and immunoglobulins can be successful. However, some children become steroid dependent and symptoms may reoccur after treatment has been finished. We present two girls with OMS, who had a prolonged clinical course lasting 4 and 9 years with many relapses. Both children developed symptoms around the age of two years. Diagnostic work-up to exclude neuroblastoma was negative. Several treatment modalities including oral steroids, dexamethasone pulses, immunoglobulin and cyclosporine were used without lasting success. In addition, cognitive impairment developed in both children. In order to prevent further clinical and mental deterioration, 6 pulses of cyclophosphamide in combination with dexamethasone pulses every 4 weeks were administered. Both children showed significant improvement of OMS symptoms. One girl is still symptom free 18 months after treatment, mild ataxia developed in the other after 12 months. Both children are mentally handicapped and in special need schools. We conclude that combination of cyclophosphamide pulses and dexamethasone pulse therapy is a therapeutic option even after a long clinical course to improve symptoms of OMS.