Overlapping Autoimmune Neurological Syndrome: A Case Report of Triple-Positive Antibody

Abstract

The presentation of several autoimmune neurological disorders in a single patient is rare and often debilitating. However, early diagnosis and efficacious treatment can lead to a significant recovery. Here, we present an interesting case of a triple antibody-positive autoimmune neurological syndrome patient who manifested the clinical features of neuromyelitis optica (NMO) spectrum disorder (NMOSD), N-methyl-D-aspartate (NMDA) receptor (NMDAR) encephalitis, and myasthenia gravis (MG). Hence, the patient manifested both central and peripheral nervous system immune-mediated neurological syndromes. A middle-aged female with a history of seropositive aquaporin-4 (AQP4) NMOSD on mycophenolate 1 g twice daily presented with severe fatigue and right eye ptosis (three months since NMOSD diagnosis) and tested positive for acetylcholine receptor (AchR) binding antibody, consistent with MG. Six months after the patient’s NMOSD diagnosis, she began to experience subacute progressive cognitive decline, behavioral changes, imbalance, anxiety/panic attacks, and paranoid delusions. NMDAR encephalitis was suspected, and she tested positive for cerebrospinal fluid NMDAR antibodies. After treatment with steroids failed, she was given two doses of rituximab 1 g, two weeks apart, and reported improvement in her symptoms shortly after the second dose.

A Patient With Miller Fisher Syndrome With Positive GQ1b and Aquaporin-4 Antibodies: Will There Be an Aquaporin-4 Antibody Associated Disorder?

“…Among these reported diseases are Sjogren’s syndrome, myasthenia gravis (MG), and N-methyl-D-aspartate receptor encephalitis (NMDAR) [ 19 , 20 , 21 ]. One report even had three different types of antibodies being positive in an NMOSD, MG, and NMDAR co-existing situation [ 22 ]. All reports focused on the “co-existing” aspect of the pathology; no attempts were made to investigate if this could be an AQP4-associated disorder.…”