Here, we present a case of late-onset Guillain-Barré syndrome (GBS) associated with COVID-19. A 70-year-old woman presented with ascending paralysis and right lower motor neuron facial weakness 2 months after COVID-19 infection. Test results for SARS-CoV-2 immunoglobulin were positive at the time of presentation. Lumbar puncture showed albuminocytological dissociation, and electrophysiology showed features of demyelination with secondary axon loss. In the published literature on GBS associated with COVID-19, almost all patients presented with neurological symptoms 1–4 weeks after the infection. GBS can be an early or late manifestation after COVID-19. Patients with signs of paraparesis and facial weakness after COVID-19 should be carefully evaluated for immune-mediated central and peripheral nervous system disorders.

Stroke-like migraine attacks after radiation therapy (SMART) are uncommon, often occurring years or decades after brain radiation therapy. This syndrome is a diagnosis of exclusion, and only about 40 cases describing SMART have been published, each one describing a constellation of symptoms and findings. Because symptoms can arise years after initial radiation therapy, the ability of physicians to recognize SMART and rule out other possible causes of symptoms is critical for the long-term care of oncology patients who have undergone cranial radiation. Here we present the case of a 55-year-old man who experienced SMART nine years after radiation therapy and who was successfully treated with steroids.

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.