Central Sleep Apnea Syndrome Can Complicate Neuromyelitis Optica Spectrum Disorder: A Case Report

Abstract

Neuromyelitis optica spectrum disorder is a rare, relapsing autoimmune disease of the central nervous system. Various initial presentations can delay diagnosis and treatment. A 14-year-old girl was admitted to the emergency department owing to respiratory insufficiency. Repeated history-taking and neuroimaging revealed an area postrema syndrome. A diagnosis of neuromyelitis optica spectrum disorder with positive aquaporin-4 antibodies has finally been established. The patient improved significantly with immunosuppressive therapy. However, her 3-year follow-up still showed sleep-disordered breathing requiring nocturnal bilevel positive airway pressure therapy. We report an original case of NMOSD leading to persistent central sleep apnea syndrome.

Keywords: area postrema syndrome; case report; central sleep apnea syndrome; children; neuromyelitis optica spectrum disorder; noninvasive ventilation; sleep-disordered breathing.

Figure 1

Timeline. PICU, pediatric intensive care unit; O₂, oxygen; NIV, non-invasive ventilation; IgIV, intravenous immunoglobulin therapy; AQP-IgG, autoantibodies against the aquaporin-4 water channel.

Figure 2

Brain MRI performed at 1.5 Tesla and limited by metallic artifacts. (A) coronal T1 weighted imaging showing a low signal intensity, (B) axial T2 weighted imaging, and (C) axial fluid attenuation inversion recovery showing a high signal intensity in the posterior part of the medulla oblongata bilaterally.

Figure 3

(A) Diagnostic sleep study without noninvasive ventilation (NIV) at day 34 after admission. Note three central apnea (cessation of airflow associated with the absence of respiratory efforts and therefore no thoracic or abdominal movements) with subsequent hypoxemia. The apnea-hypopnea index in this study was 110/h. The mean respiratory rate was 3/min. THO, thoracic belt signal; ABD, abdominal belt signal; PTAF, pressure transducer airflow; SpO2, saturation measured by pulse oximetry; Pléth., plethysmography waveform derived from the pulse oximeter; TcPCO₂, transcutaneous carbon dioxide monitoring. (B) Diagnostic sleep study with and without NIV, 3 years after the diagnosis. No respiratory events occurred during the first part of the night with NIV and the SpO2 was above 90% all the time. During the second part of the night without NIV, the apnea-hypopnea index was 110/h and the SpO2 dropped below 90% for 29 min over 5 h with minimal SpO2 of 80%. No recovery of the central sleep apnea syndrome occurred between those two sleep studies. IPAP, inspiratory airway pressure; EPAP, expiratory airway pressure; cmH₂O, centimeters of water; Resp events, Respiratory events.