A54-04 Acute Neurological Hypercapnic Respiratory Failure Due to Neuromyelitis Optica Spectrum Disorder

Abstract Introduction Neuromyelitis optica is an autoimmune-mediated idiopathic inflammatory demyelinating disease that is characterized by recurrent attacks of optic neuritis, transverse myelitis, and area postrema syndrome (APS) but may extend up to the brainstem, resulting in life-threatening respiratory failure. The 2015 International Panel for NMO Diagnosis widened the concept ofneuromyelitis optica to include a wider range of clinical features, introducing the term neuromyelitis optica spectrum disorder (NMOSD). Patients with NMOSD are seropositive for disease-specific and pathogenic aquaporin-4 (AQP4) antibodies, which are key markers for its diagnosis. The exact incidence and prevalence of NMOSD remain unclear. Description of the case A 66-year-old African American female with a Past medical history of end-stage renal disease on hemodialysis, a history of chronic right basal ganglia infarct, and bilateral vision loss presented with progressive generalized weakness, bilateral vision loss, and slurred speech. Initial imaging workup for suspected acute stroke was negative. Patient developed altered mental status during her in-patient dialysis session, followed by worsening lethargy and hypercapnic respiratory failure, which required intubation and mechanical ventilation. In the ICU, she exhibited new-onset bilateral arm weakness with loss of tone in both of her arms. The patient was also noted to exhibit double triggering on pressure support ventilation. New onset bilateral upper extremity weakness prompted further workup with MRI cervical, thoracic, and Lumbar spine, which revealed patchy T2 hyperintensities in the medulla and cervical cord, prominently at C3 and C6-C7 as shown in Figure 1. Similarly, small T2 hyperintense lesions were present at T5 and T10. Further Investigations included CSF analysis, EEG, and acetylcholine receptor and MuSK antibody test, which were unremarkable. However, the Aquaporin-4 antibody was positive, confirming NMOSD.. Following the diagnosis, she received plasma exchange and pulse dose corticosteroids, leading to gradual recovery and successful extubation to noninvasive ventilation. A short course of IVIG was given for residual weakness, resulting in mild neurological improvement. She regained partial upper-limb movement, followed commands, and communicated verbally. Discussion and Importance Involvement of the cervical spine, specifically C3-C5, which contains phrenic nerve nuclei, can impair diaphragmatic function, causing hypercapnic respiratory failure in NMOSD. Prompt recognition and aggressive management of acute NMOSD attacks with high dose intravenous corticosteroid, IVIG, and plasma exchange are crucial in preventing further neurological worsening and improving clinical outcomes. This case signifies the importance of considering NMOSD in patients with unexplained acute hypercapnic respiratory failure and multifocal CNS lesions This abstract is funded by: none