Tanimoto Takahiko, Eriguchi Yoshihiro, Sato Tomonori, Yonekawa Akiko, Miyake Noriko, Akashi Koichi, Shimono Nobuyuki
Department of Clinical Immunology and Rheumatology / Infectious Disease, Kyushu University Hospital, Fukuoka, Japan.
Department of Infectious Diseases, Kagoshima Seikyo Hospital, Kagoshima, Japan.
Int Med Case Rep J. 2023 Mar 27;16:201-207. doi: 10.2147/IMCRJ.S402537. eCollection 2023.
Platypnea-orthodeoxia syndrome (POS) is a rare disorder associated with coronavirus disease 2019 (COVID-19) pneumonia. However, POS may be underdiagnosed. We report the case of a 59-year-old female patient with POS complicated by pulmonary embolism in COVID-19. Imaging revealed ground-glass opacities predominantly in the lower lobes and a pulmonary embolus in the right upper lobe. She was diagnosed with POS due to marked postural discrepancies between supine and upright oxygen saturations and blood oxygenation. Intracardiac shunt, one of the etiologies of POS, was not detected by bubble contrast echocardiography, and postural de-saturation gradually improved with methylprednisolone and edoxaban administration. In our literature review, only 3 of the 16 patients with POS associated with COVID-19 had cardiac shunting, suggesting that moderate to severe COVID-19 causes POS without cardiac shunts. COVID-19-associated vasculopathy and lower lung lesion predominance in COVID-19 pneumonia may cause ventilation-perfusion mismatch due to gravitational shunting of blood into the poorly ventilated lower lungs in the upright position, which may ultimately cause POS. Hypoxemia impedes rehabilitation, whereas early initiation of supine positioning in bed, with knowledge of the pathophysiology of POS, may have a positive effect.
平卧呼吸-直立性低氧血症综合征（POS）是一种与2019冠状病毒病（COVID-19）肺炎相关的罕见疾病。然而，POS可能未得到充分诊断。我们报告了一例59岁女性COVID-19患者并发肺栓塞的POS病例。影像学检查显示磨玻璃影主要位于下叶，右上叶有肺栓塞。由于仰卧位和直立位血氧饱和度及血液氧合存在明显的体位差异，她被诊断为POS。经气泡对比超声心动图未检测到作为POS病因之一的心内分流，使用甲泼尼龙和依度沙班后体位性低氧血症逐渐改善。在我们的文献综述中，16例与COVID-19相关的POS患者中只有3例存在心脏分流，这表明中度至重度COVID-19可导致无心脏分流的POS。COVID-19相关血管病变以及COVID-19肺炎中下肺病变占优势，可能由于直立位时血液因重力作用分流至通气不良的下肺，导致通气-灌注不匹配，最终可能导致POS。低氧血症会妨碍康复，而了解POS的病理生理学后早期在床上采取仰卧位可能会产生积极效果。
