Simões Joana Paiva, Alves Ferreira Ana Rita, Almeida Pedro Martins, Trigueiros Frederico, Braz Armando, Inácio João Rodrigues, Medeiros Fábio Cota, Braz Sandra, Pais de Lacerda António
Department of Internal Medicine II at Santa Maria Hospital, Centro Hospitalar Universitário Lisboa Norte, EPE, Portugal.
Department of Hematology at Santa Maria Hospital, Centro Hospitalar Universitário Lisboa Norte, EPE, Portugal.
Respir Med Case Rep. 2021;32:101359. doi: 10.1016/j.rmcr.2021.101359. Epub 2021 Jan 31.
Organizing pneumonia (OP) is a sub-acute process of pulmonary tissue repair secondary to lung injury, defined histopathologically by intra-alveolar buds of granulation tissue within the lumen of distal pulmonary airspaces. It can be either cryptogenic or secondary (SOP) to different clinical conditions, namely infections. Despite being nonspecific, its diagnosis can be made by the association of clinical and imaging criteria. We report two cases of OP associated to SARS-CoV-2 pneumonia, admitted at a Portuguese tertiary hospital unit dedicated to COVID-19. Both patients presented with severe respiratory failure with need of invasive mechanical ventilation. After initial recovery, there was worsening of dyspnea and hypoxemic respiratory failure with increase in inflammatory markers. Chest CT revealed an OP pattern. Other conditions such as superinfection, auto-immune disease and iatrogenic etiology, were excluded and corticotherapy at a dose of 1 mg/kg/day was administered. Chest CT follow up of both our patients showed complete resolution of OP pattern, with mild to moderate residual pulmonary fibrosis without honeycombing. There is no OP to SARS-CoV-2 case series yet published describing the progress of patients after corticotherapy, although the association between systemic corticosteroids and lower all-cause mortality in patients with COVID-19 has been recently established. It is possible that, as has been described with other viruses, OP secondary to SARS-CoV-2 represents an immunological process after initial infection, presenting with elevation of inflammatory markers and cytokines storm in the bloodstream and lung tissue, which may explain the favorable response to corticosteroids.
机化性肺炎（OP）是肺损伤继发的肺组织亚急性修复过程，组织病理学上定义为远端肺气腔腔内肉芽组织的肺泡内芽。它可以是隐源性的，也可以是继发于不同临床情况（即感染）的继发性机化性肺炎（SOP）。尽管缺乏特异性，但其诊断可通过临床和影像学标准综合判断。我们报告了两例与SARS-CoV-2肺炎相关的机化性肺炎病例，患者在一家葡萄牙三级医院的COVID-19专科病房住院。两名患者均出现严重呼吸衰竭，需要有创机械通气。在初步恢复后，出现呼吸困难加重和低氧性呼吸衰竭，炎症标志物升高。胸部CT显示有机化性肺炎的表现。排除了其他情况，如重叠感染、自身免疫性疾病和医源性病因，并给予1mg/kg/天的皮质激素治疗。对我们两名患者的胸部CT随访显示，机化性肺炎表现完全消退，伴有轻度至中度的残余肺纤维化，无蜂窝状改变。尽管最近已证实全身性皮质类固醇与COVID-19患者全因死亡率降低之间存在关联，但尚未有已发表的关于SARS-CoV-2相关机化性肺炎病例系列描述皮质激素治疗后患者的病情进展。与其他病毒情况类似，SARS-CoV-2继发的机化性肺炎可能代表初始感染后的免疫过程，表现为血液和肺组织中炎症标志物升高和细胞因子风暴，这可能解释了对皮质类固醇的良好反应。
