Possible coexistence of MOG-IgG-associated disease and anti-Caspr2 antibody-associated autoimmune encephalitis: a first case report

Abstract

Myelin oligodendrocyte glycoprotein antibody-associated disease has been proposed as a separate inflammatory demyelinating disease of the central nervous system (CNS) since the discovery of pathogenic antibodies against myelin oligodendrocyte glycoprotein (MOG-IgG). Antibodies targeting contactin-associated protein-like 2 (Caspr2), a component of voltage-gated potassium channel (VGKC) complex, have been documented to be associated with a novel autoimmune synaptic encephalitis with a low incidence. Herein, we reported an adult female with initial presentation of decreased vision in the right eye and subsequent episodes of neuropsychiatric disturbance including hypersomnia, agitation, apatheia, and memory impairment. Magnetic resonance imaging (MRI) revealed multiple lesions scattered in brain, brainstem, and cervical and thoracic spinal cord, showing hypointensity on T1-weighted images, hyperintensity on T2-weighted and fluid attenuated inversion recovery (FLAIR) images. Heterogenous patchy or ring-like enhancement was observed in the majority of lesions. The detection of low-titer MOG-IgG exclusively in cerebrospinal fluid (CSF; titer, 1:1) and Caspr2-IgG in both serum and CSF (titers, 1:100 and 1:1) led to a possible diagnosis of coexisting MOG-IgG-associated disease (MOGAD) and anti-Caspr2 antibody-associated autoimmune encephalitis. The patient was treated with immunosuppressive agents including corticosteroids and immunoglobulin, and achieved a sustained remission. To the best of our knowledge, this is the first report on the possible coexistence of MOGAD and anti-Caspr2 antibody-associated autoimmune encephalitis, which advocates for the recommendation of a broad spectrum screening for antibodies against well-defined CNS antigens in suspected patients with autoimmune-mediated diseases of the CNS.

The Antibody Assay in Suspected Autoimmune Encephalitis From Positive Rate to Test Strategies

“…The results showed that the antibody titers of serum and CSF were 1:1 to 1:100. A previous study revealed that the titers and types of antibodies also changed during the course of disease progression (28)(29)(30), which can be used for disease assessment and prognosis.…”

Coexistence of Myelin Oligodendrocyte Glycoprotein Immunoglobulin G and Neuronal or Glial Antibodies in the Central Nervous System: A Systematic Review

“…Fifty-three relevant studies were identified after title and abstract screening. After reading the full texts and reviewing the references of the retrieved articles, 35 studies were finally included in the qualitative synthesis, of which 14 were retrospective studies [ 11 , 15 , 16 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ] and 21 were case reports [ 12 , 13 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 ]. A total of 113 patients (46 males and 67 females) were reported to show the coexistence of MOG-IgG and neuronal or glial antibodies in these 35 studies.…”

“…In recent years, the spectrum of MOGAD has been expanded due to the detection of MOG-IgG coexisting with other neuronal or glial antibodies, especially in patients with atypical clinical symptoms and/or neuroradiological features [ 11 ]. Our group recently reported two patients with atypical MOGAD in whom MOG-IgG coexisted with glial fibrillary acidic protein (GFAP)-IgG [ 12 ] and contact protein-associated 2 (CASPR2)-IgG [ 13 ], respectively. An increasing number of studies have also demonstrated the coexistence of MOG-IgG with other antibodies, such as N-Methyl-D-Aspartate Receptor (NMDAR)-IgG [ 14 ] and AQP4-IgG [ 15 , 16 ], which has drawn extensive attention and generated discussion.…”

Autoimmune diseases and cancers overlapping with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): A systematic review

“… 68 , 75 Given the overall rarity of double positive cases based on the results of the larger studies, and considering the superior specificity of the AQP4-IgG test compared to the MOG-IgG test, and that a reliable cell-based-assay (CBA) for detecting MOG-IgG has been available just recently (2017), there is a high possibility that most of the double positive cases may likely be AQP4-IgG + NMOSD with false positive MOG-IgG test results, especially in reports made before this time with using enzyme-linked immunosorbent assay (ELISA). 68 , 75 …”