Mycophenolate mofetil in paediatric autoimmune or immune-mediated diseases of the central nervous system: clinical experience and recommendations

Long-Term Outcomes of Pediatric Vogt-Koyanagi-Harada Disease

PURPOSE

To study the clinical presentation, outcomes, and factors affecting the final visual outcome of Vogt-Koyanagi-Harada (VKH) disease in the pediatric age group.

METHODS

Pediatric patients who were diagnosed with VKH at King Khaled Eye Specialist Hospital (KKESH) between 2007 and 2024. Demographic and clinical data were collected and analyzed for an association with the final visual outcome.

RESULTS

Sixty-nine children (138 eyes) with an age range upon presentation from 2 years old to 18 years old and a mean age of 12.2 ± 4.0 years were included. The mean duration of follow-up was 6.5 ± 3.1 years. There were 35 (50.7%) males and 34 (49.3%) females. Sixty children (86.9%) had initial-onset acute VKH, while 9 children had chronic recurrent VKH. At initial presentation, the mean LogMAR BCVA was 0.6 (Snellen = 20/70) ± 0.6. Children with chronic recurrent VKH presented at an earlier age (p = 0.003), had more severe corneal involvement (p < 0.001) and more severe AC reaction (p < 0.001). Cataract developed in 33 (23.9%) eyes, 54 eyes (39.1%) developed glaucoma, and 36 eyes (26.1%) developed choroidal neovascular membranes (CNVM). Children with chronic recurrent VKH disease had higher rates of pre-existing or developing cataract, glaucoma, and CNVM. On the last visit, the BCVA improved from an average of 20/70 to 20/50. The visual improvement was statistically significant (p = 0.005).

CONCLUSIONS

Good visual outcomes can be achieved in the majority of pediatric patients with VKH disease. Children with chronic recurrent VKH disease present with more aggressive anterior segment inflammation, have higher risk of developing ocular complications, and less favorable visual outcomes.

Current and emerging therapies for autoimmune encephalitis

INTRODUCTION

Autoimmune encephalitis (AIE) is an inflammatory neurological disorder often associated with autoantibodies targeting neural or glial antigens. Patients with AIE are often treated with immunotherapy, but multiple questions remain about the optimal treatment strategy for common AIE subtypes.

AREAS COVERED

The authors conducted a literature search of PubMed articles and Google Scholar articles using keywords 'autoimmune encephalitis,' 'anti-NMDA receptor encephalitis, 'LG1 encephalitis' from 2005 to 2024. This review briefly outlines the proposed pathophysiology of AIE with autoantibodies toward cell surface vs intracellular antigens. Next, the authors discuss treatments commonly used for AIE, and provide guidance on side effects and monitoring, and the evidence for treatment approaches for anti-NMDAr and LGI1 encephalitis is reviewed. In the final section, an overview of ongoing clinical trials and future therapies for AIE is provided.

EXPERT OPINION

Patients with AIE benefit from treatment with immunotherapy, but the evidence supporting specific treatment strategies is limited to observational studies. Successful clinical trials for AIE will provide new therapy options for patients, and the next generation of therapies may provide more targeted approaches to treating the condition.

Immunotherapy for autoimmune encephalitis

Autoimmune encephalitis (AE) is increasingly recognized as a cause of brain disorders that greatly benefit from immunotherapy. Starting treatment quickly and increasing the use of immunotherapy can lead to better results for AE patients. Currently, there are standardized treatment guidelines for treating AE. First-line therapy includes intravenous corticosteroids, plasma exchange, and intravenous immunoglobulin. Second-line therapy involves rituximab, cyclophosphamide, mycophenolate mofetil, and azathioprine. Third-line therapy uses agents that deplete plasma cells (bortezomib, daratumumab, and obinutuzumab), drugs that modulate cytokines (tocilizumab, anakinra, tofacitinib, and interleukin-2), and treatments that target intrathecal immune cells (intrathecal methotrexate). This review aims to summarize the immunotherapeutic strategies available for treating AE and provide an update on refractory AE.

Controversies in immunotherapy for anti-NMDA receptor encephalitis: a scoping review with a proposal of operational definitions

Anti-NMDA receptor encephalitis (NMDARE), an autoimmune encephalitis associated with autoantibodies against the N-methyl-D-aspartate (NMDA) receptor, affects predominantly young women and is associated with psychiatric symptoms, seizures, movement disorders, and autonomic instability. Traditional treatments of anti-NMDA receptor encephalitis involve corticosteroids, intravenous immunoglobulin, plasmapheresis, cyclophosphamide, and rituximab. However, many controversies remain in the treatment for NMDA receptor encephalitis, such as optimal timing and combination of different immunotherapies, the role of newer strategies (e.g., bortezomib or tocilizumab) for severe and refractory patients, and the need or not for long-term immunosuppression. Our goal was to perform a scoping review to discuss the controversial topics of immunotherapy for NMDA receptor encephalitis and propose operational definitions to guide clinical practice and future research in the field.

Rasmussen's Encephalitis: A Literary Review

Usually affecting one hemisphere of the brain, Rasmussen's encephalitis (RE) is a persistent inflammatory disease of unclear origin. Rasmussen and colleagues presumed a viral etiology of the sickness in their first description. Later, the condition was linked to autoantibodies that were in the blood. Recently, it was shown that the cause of RE was a cytotoxic T-cell reaction to neurons. RE may be identified histopathologically by cortical inflammation, neuronal degeneration, and cerebral hemispheric-specific gliosis. The hemisphere is affected by increasing multilocular inflammation. To diagnose patients sooner and to evaluate whether the aforementioned phenomena are primary or secondary, it is essential to continue the search for a primary immunological or viral component. This information is crucial for determining the effectiveness of immunotherapy. RE-related seizures can only now be managed surgically. The only procedure that works is complete hemispheric disconnection (hemidisconnection), which may be done as either a (functional) hemispherectomy or hemispherectomy. Although thalidomide has been anecdotally reported, its safety profile prevents it from being used as a first-line treatment despite having a noticeable effect on the frequency and severity of seizures. Finding the disease's root causes more quickly by combining descriptive clinical studies, genetic testing, and early histological evaluation of RE tissue specimens to check for viral and autoimmune pathogenesis. Creating appropriate in vitro or animal models will enable the study of causality, perhaps directing clinical trials.

Experience with the use of mycophenolate mofetil in juvenile idiopathic inflammatory myopathies

OBJECTIVE

The objective of this study was to evaluate the efficacy and safety of MMF in juvenile idiopathic inflammatory myopathies (JIIMs).

METHODS

Patients diagnosed with JIIM and treated with MMF enrolled in the Juvenile Dermatomyositis Research Group (JDRG) in the UK or followed at the Giannina Gaslini Institute in Genoa, Italy, were included. The following information was collected retrospectively at MMF initiation, at 3, 6 and 12 months after treatment start, and at last follow-up visit: clinical manifestations, laboratory data, physicians' subjective assessment of disease activity, standardized outcome measures of muscle strength/endurance, cutaneous disease activity, physical function, global disease activity, cumulative damage, and ongoing treatment.

RESULTS

Of the 29 patients included, 23 had juvenile DM and 6 had overlap myositis. During administration of MMF, improvement in measures of muscle strength, skin disease activity, and overall disease activity was seen, with an increase in the frequency of normal scores for Manual Muscle Test-8 from 50.0% to 83.3%, Childhood Myositis Activity Score from 53.5% to 88.9%, muscle component of DAS from 55.2% to 84.2%, skin component of DAS from 31.0% to 42.1%, visual analogue scale for skin disease activity from 25.0% to 47.4%, and visual analogue scale for overall disease activity from 7.1% to 42.1%. The number of patients with inactive disease increased from 10.3% at baseline to 68.5% at last follow-up. CS dose was significantly reduced, from 0.3 to 0.1 mg/kg/day. No relevant side effects were reported.

CONCLUSION

Our experience suggests that MMF is a valuable therapeutic option for the management of JIIM.

Autoantibody Encephalitis: Presentation, Diagnosis, and Management

Autoantibody encephalitis causes distinct clinical syndromes involving alterations in mentation, abnormal movements, seizures, psychiatric symptoms, sleep disruption, spasms, and neuromyotonia. The diagnoses can be confirmed by specific antibody tests, although some antibodies may be better detected in spinal fluid and others in serum. Each disorder conveys a risk of certain tumors which may inform diagnosis and be important for treatment. Autoantibodies to receptors and other neuronal membrane proteins are generally thought to be pathogenic and result in loss of function of the targets, so understanding the pharmacology of the receptors may inform our understanding of the syndromes. Patients may be profoundly ill but the syndromes usually respond to immune therapy, although there are differences in the types of immune therapy that are thought to be most effective for the various disorders.

Pediatric Neuromyelitis Optica Spectrum Disorder: Case Series and Literature Review

Neuromyelitis Optica Spectrum Disorder (NMOSD) is a central nervous system (CNS) inflammatory demyelinating disease characterized by recurrent inflammatory events that primarily involve optic nerves and the spinal cord, but also affect other regions of the CNS, including hypothalamus, area postrema and periaqueductal gray matter. The aquaporin-4 antibody (AQP4-IgG) is specific for NMOSD. Recently, myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) have been found in a group of AQP4-IgG negative patients. NMOSD is rare among children and adolescents, but early diagnosis is important to start adequate therapy. In this report, we present cases of seven pediatric patients with NMOSD and we review the clinical and neuroimaging characteristics, diagnosis, and treatment of NMOSD in children.

Effectiveness of Mycophenolate Mofetil in the Treatment of Pediatric Anti-NMDAR Encephalitis: A Retrospective Analysis of 6 Cases

Objective: To explore the effectiveness and safety of mycophenolate mofetil (MMF) as a second-line medication in the treatment of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, the most common and severe autoimmune encephalitis. Methods: The clinical data of six children with anti-NMDAR encephalitis admitted to the First Hospital of Jilin University were retrospectively analyzed, and the effectiveness and safety of MMF were evaluated. Results: Six children with anti-NMDAR encephalitis were treated with MMF in the 2nd or 3rd treatment disease event (3 cases vs. 3 cases). MMF initiation was mean 19.2 months (range 6-39 months) after disease onset at a mean dose of 25.6 mg/kg (range 19.6-28.4 mg/kg) for 14 months (range 6-26 months). Only two patients had transient mild diarrhea within 2 weeks of MMF application. During follow-up, one patient relapsed whilst on MMF, one patient discontinued MMF, and 4 cases were still on MMF. Conclusion: The use of MMF in anti-NMDAR encephalitis may be effective and safe. MMF can be used as one of the relapse prevention options in patients who already have relapsed or possibly even after the first event. Delayed use may be the main reason for MMF failure.

Management Strategies of Patients with Neuromyelitis Optica Spectrum Disorder During the COVID-19 Pandemic Era

The ongoing coronavirus (COVID-19) pandemic is a global health emergency of international concern and has affected management plans of many autoimmune disorders. Immunosuppressive and immunomodulatory therapies are pivotal in the management of neuromyelitis optica spectrum disorder (NMOSD), potentially placing patients at an increased risk of contracting infections such as COVID-19. The optimal management strategy of NMOSD during the COVID-19 era remains unclear. Here, however, we examined the evidence of NMOSD disease-modifying therapies (DMTs) use during the present period and highlighted different scenarios including treatment of relapses as well as initiation and maintenance of DMTs in order to optimize care of NMOSD patients in the COVID-19 era.

Pediatric NMOSD: A Review and Position Statement on Approach to Work-Up and Diagnosis

Neuromyelitis Optica Spectrum Disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) primarily affecting the optic nerves and spinal cord, but also involving other regions of the CNS including the area postrema, periaqueductal gray matter, and hypothalamus. Knowledge related to pediatric manifestations of NMOSD has grown in recent years, particularly in light of newer information regarding the importance of not only antibodies to aquaporin 4 (AQP4-IgG) but also myelin oligodendrocyte glycoprotein (MOG-IgG) in children manifesting clinically with this syndrome. In this review, we describe the current state of the knowledge related to clinical manifestations, diagnosis, and chronic therapies for children with NMOSD, with emphasis on literature that has been published in the last 5 years. Following the review, we propose recommendations for the assessment/follow up clinical care, and treatment of this population.