NMDAR (N-methyl-D-aspartate receptor) encephalitis in a patient with MS (multiple sclerosis): a rare and challenging case

Glucocorticoid-dependent multiple sclerosis overlapping anti-NMDA receptor encephalitis: a case report and literature review update

BACKGROUND

Previous studies suggest a relationship between central nervous system inflammatory demyelinating diseases and anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis. Also, the overlap between anti-NMDAR encephalitis and multiple sclerosis (MS) has been reported. However, the pathogenesis and clinical characteristics are still obscure.

CASE PRESENTATION

A 33-year-old woman presented with diplopia and sensory ataxia at the onset. The cerebrospinal fluid (CSF) anti-NMDAR antibodies were positive (1:3.2), and nuclear magnetic resonance imaging (MRI) showed bilateral centrum ovale and lateral ventricle demyelinating lesions. Therefore, she was diagnosed with anti-NMDAR encephalitis. After administering intravenous immunoglobulin and oral prednisone, her lesions disappeared, and symptoms were relieved. The condition was maintained with a low dose of prednisone, but her lesions reappeared on MRI. Consequently, immunomodulatory therapy of mycophenolate mofetil was initiated. However, she developed dysarthria and right limb ataxia after 10 months with a positive CSF anti-NMDAR antibody (1:1) and positive oligoclonal band. The MRI showed symmetrical multiple demyelinating lesions. Considering the MS diagnosis, her neurological dysfunction again improved significantly after intravenous methylprednisolone. Unfortunately, her symptoms aggravated for the second time when teriflunomide was started. Finally, her condition was controlled again with oral prednisone.

CONCLUSIONS

Consistent with previous cases of overlapping anti-NMDAR encephalitis and MS, patients often show atypical symptoms on MRIs and immunological tests. The overlap cannot be arbitrarily treated because of the recurrence of previous diseases. Long-term follow-up, dynamic antibody monitoring, and MRI examination are crucial for these patients. The special dependency of the patient on glucocorticoids in this study has been rarely reported, which may guide the treatment of insensitivity to disease-modifying therapy in recurrent overlapping anti-NMDAR encephalitis and MS.

Overlapping anti-NMDAR encephalitis and multiple sclerosis: A case report and literature review

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune-mediated disease characterized by complicated neuropsychiatric symptoms and the detection of cerebrospinal fluid antibodies against the GluN1 subunit of the NMDAR. With the proposed clinical method, more anti-NMDAR encephalitis patients have been discovered since its first report. However, anti-NMDAR encephalitis overlapping with multiple sclerosis (MS) is rare. Herein we report a male patient with anti-NMDAR encephalitis who developed MS in mainland China. Furthermore, we summarized the characteristics of patients who were diagnosed with overlapping MS and anti-NMDAR encephalitis in previous studies. Additionally, we pioneered the use of mycophenolate mofetil in immunosuppressive therapy, providing a novel therapeutic alternative for overlapping anti-NMDAR encephalitis and MS.

Clinical Characteristics of Anti-N-Methyl-d-Aspartate Receptor Encephalitis Overlapping with Demyelinating Diseases: A Review

Anti-N-methyl-d-aspartate receptor encephalitis (NMDARe), a common autoimmune encephalitis, can be accompanied by demyelinating disorders, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). To compare the clinical characteristics of patients with different overlapping syndromes, we searched the PubMed database and performed a systematic review. Of the 79 patients with overlapping syndromes, 15 had MS, 18 had aquaporin-4-antibody-positive NMOSD (AQP4-Ab-positive NMOSD), and 46 had MOGAD. Compared with classical NMDARe, overlapping syndromes showed atypical symptoms, such as limb weakness, sensory disturbance, and visual impairments in addition to the main symptoms of NMDARe and a lower ratio of ovarian teratoma. Patients with MOGAD overlap were the youngest, while patients with MS and AQP4-Ab-positive NMOSD overlap tended to be older than patients with classical NMDARe. A majority of patients with NMDARe who overlapped with MS or AQP4-Ab-positive NMOSD were female, but this was not the case for patients overlapped with MOGAD. When NMDARe and demyelinating diseases occurred sequentially, the interval was the longest in patients with NMDARe overlapped with MS. A favorable outcome was observed in patients overlapping with MOGAD, but no robust comparison can be drawn with the patients overlapping with AQP4-Ab-positive NMOSD and MS regarding the small number of available data. The long-term prognosis of overlapping syndromes needs further investigation.

Anti-N-methyl-D-aspartate receptor encephalitis presenting as atypical psychosis in multiple sclerosis: a case report

BACKGROUND

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an autoimmune disorder which often presents with neuropsychiatric symptoms. A large proportion of cases are associated with an identifiable tumor, most commonly ovarian teratoma. However, recent literature has also described an overlap of anti-NMDAR encephalitis and demyelinating syndromes. Cases have been reported of anti-NMDAR encephalitis in patients with ADEM, optic neuritis, myelitis and multiple sclerosis. This link is considered rare, however has important clinical implications as treatments and prognosis may differ.

CASE PRESENTATION

A 33-year-old female with a history of multiple sclerosis presented with new-onset neuropsychiatric symptoms. After substance-induced psychosis was ruled out, she was admitted to the medical ward for work up of psychosis secondary to multiple sclerosis. However, the consultation-liaison psychiatry service noted atypical symptoms which were concerning for autoimmune encephalitis. Admission to a psychiatric inpatient ward was deferred. Anti-NMDAR encephalitis was diagnosed with CSF analysis demonstrating lymphocytic pleocytosis and anti-NMDAR antibodies. In addition to first-line treatment of encephalitis with steroids, second-line immunotherapies were also implemented given the patient's underlining demyelinating syndrome. The patient's neurologic and psychiatric symptoms began to improve.

CONCLUSIONS

There is literature to demonstrate a possible connection between anti-NMDAR encephalitis and demyelinating syndromes. As such, autoimmune encephalitis should be considered in patients with multiple sclerosis presenting with atypical symptoms. Determining the correct diagnosis is crucial to inform the appropriate treatment protocol, and to improve prognosis.

Case Report: Antibodies to the N-Methyl-D-Aspartate Receptor in a Patient With Multiple Sclerosis

The association between multiple sclerosis and anti-N-Methyl-D-Aspartate receptor encephalitis is limited to merely a few case reports, and the exploration of the pathogenic mechanisms underlying the overlap of these two disease entities is very limited. Therefore, case reports and literature review on N-Methyl-D-aspartate receptor antibody in patients with multiple sclerosis are unusual and noteworthy. A young female had the first episode of paresthesia and motor symptoms with positive anti-N-Methyl-D-Aspartate receptor antibody and recovered after immunotherapy, and at the first relapse, the patient developed disorders of consciousness with positive anti-N-Methyl-D-Aspartate receptor antibody, findings of magnetic resonance imaging showed features of autoimmune encephalitis, which was also controlled by immunotherapy. At the second relapse, anti-N-Methyl-D-Aspartate receptor antibody turned negative while oligoclonal bands presented positive, and findings of magnetic resonance imaging showed features of multiple sclerosis. Afterwards, we followed the patient after receiving disease modifying treatment to monitor the efficacy and safety of teriflunomide. Based on literature review, demyelinating diseases patients with anti-neuronal antibody have complex, diverse and atypical symptoms; therefore, high attention and increased alertness are necessary for neurologists. Conclusively, anti-neuronal antibody may present in many neuroinflammatory conditions, and diagnostic criteria should be used with caution if the clinical presentation is atypical, and neurologists should not rely excessively on laboratory tests to diagnose neurological diseases. Timely and comprehensive examination and consideration as well as early standardized treatment are the key factors to reduce patient recurrence and obtain a good prognosis.

Case Report: Overlapping Multiple Sclerosis With Anti-N-Methyl-D-Aspartate Receptor Encephalitis: A Case Report and Review of Literature

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune disorder mediated by NMDAR antibodies, typically manifesting as behavioral complaints, psychosis, seizures, movement disorders, hypoventilation, and autonomic dysfunction. In recent years, the predisposing factors and pathophysiological mechanisms of anti-NMDAR encephalitis have been tried to be clarified. It has been recognized that an overlap may be observed between anti-NMDAR encephalitis and inflammatory demyelinating disease. However, anti-NMDAR encephalitis is rarely associated with multiple sclerosis. Here, we describe a Chinese female patient diagnosed with relapsing remitting multiple sclerosis who developed anti-NMDAR encephalitis. Further, we discuss the previously reported literature.

Catatonia in N-methyl-d-aspartate receptor antibody encephalitis: Phenomenological characteristics from a systematic review of case reports

OBJECTIVE

To ascertain the phenomenological characterisation of catatonia in N-methyl-d-aspartate receptor antibody encephalitis (NMDAr-AbE).

METHODS

A systematic review of case reports was undertaken in accordance with PRISMA guidelines. Case reports of NMDAr-AbE containing sufficient information on the cases' clinical presentation and meeting the study's inclusion criteria were selected. Cases were searched for clinical data in keeping with core catatonic signs by applying the screening instrument of the Bush-Francis Catatonia Rating Scale. When two or more core signs were ascertained catatonia was considered to be present.

RESULTS

2645 records were identified through the database search. Following screening and application of eligibility/inclusion criteria 139 articles were selected reporting on 189 individual subjects. Catatonia was present in 60% of these cases. The most prevalent signs were immobility/stupor (70%), mutism (67%), excitement (50%), posturing/catalepsy (34%), stereotypies (31%), and rigidity (30%). Immobility/stupor and excitement co-occurred in the same patient in 33% of cases.

CONCLUSION

The phenomenological profile of catatonia in this sample of cases of NMDAr-AbE was characterised by a preponderance of signs in the hypokinetic spectrum. However, excitement often co-occurred in these patients suggesting that fluctuations in catatonic semiology may be frequent.