BACKGROUND Acute exacerbation of chronic fibrosing idiopathic interstitial pneumonias (AE-IIPs) is associated with a high mortality rate. In 2016, an international working group proposed a revised diagnostic criteria for AE-IIPs, suggesting that it be classified as idiopathic or triggered. Many factors are known to trigger AE-IIPs, including surgery, infection, and drugs. However, it is unknown which AE-IIPs triggers have a worse prognosis. We aimed to investigate the prognosis of patients with various clinical types of AE-IIPs, particularly infection-triggered, non-infection triggered, and idiopathic AE-IIPs. METHODS We retrospectively collected data from 128 chronic fibrosing IIPs (CF-IIPs) patients who were hospitalized by respiratory failure between April 2009 and March 2019 at Juntendo University Hospital. Among these patients, we evaluated 79 patients who developed AE-IIPs and 21 who developed pneumonia superimposed on CF-IIPs. Patients with AE-IIPs were classified into three types: idiopathic, infection-triggered, and non-infection-triggered AE-IIPs. We analyzed differences in patient characteristics, examination findings; level of serum markers, results of pulmonary function, and radiological findings, prior treatment for baseline CF-IIPs, and prognosis. We then evaluated the risk factor for early death (death within 30 days from the onset of AE-IIPs) associated with AE-IIPs. RESULTS Among the patients who developed AE-IIPs, 34 were characterized as having idiopathic, 25 were characterized as having infection-triggered, and 20 were categorized as having non-infection-triggered AE-IIPs. Survival time for pneumonia superimposed on IIPs was significantly longer than that for any AE-IIPs. Survival time for bacterial pneumonia superimposed on CF-IIPs was significantly longer than that for AE-IIPs (for each idiopathic and all triggered IIPs). Thereafter, survival time for infection-triggered was significantly longer than for idiopathic or non-infection-triggered AE-IIPs. The mortality rate was significantly lower in infection-triggered AE-IIPs than in other types of AE-IIPs. Furthermore, the incidence of infection-triggered AE-IIPs in winter was significantly higher than that in other seasons. Moreover, the clinical AE-IIPs types and radiological findings at AE-IIP onset were significant risk factors for AE-IIPs-induced early death. CONCLUSIONS Our findings suggest that patients with infection-triggered AE-IIPs can expect a better prognosis than can patients with other clinical types of AE-IIPs.

中文翻译：

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特发性间质性肺炎伴不同病因急性加重的患者之间的预后差异：一项回顾性研究。

背景技术慢性纤维化特发性间质性肺炎（AE-IIP）的急性恶化与高死亡率相关。2016年，一个国际工作组提出了针对AE-IIP的修订诊断标准，建议将其分类为特发性或触发性。已知许多因素会触发AE-IIP，包括手术，感染和药物。但是，尚不清楚哪些AE-IIP触发可预后更差。我们旨在调查具有各种临床类型的AE-IIP的患者的预后，尤其是感染触发，非感染触发的和特发性AE-IIP。方法我们回顾性收集2009年4月至2019年3月在Juntendo大学医院因呼吸衰竭住院的128例慢性纤维化IIP（CF-IIP）患者的数据。在这些患者中，我们评估了79例发生AE-IIP的患者和21例发生在CF-IIP上的肺炎。患有AE-IIP的患者分为三种类型：特发性，感染触发和非感染触发的AE-IIP。我们分析了患者特征，检查结果的差异；血清标志物水平，肺功能结果和影像学发现，基线CF-IIP的既往治疗和预后。然后，我们评估了与AE-IIP相关的早期死亡（在AE-IIP发作后30天内死亡）的危险因素。结果在发生AE-IIP的患者中，有34例为特发性，有25例为感染触发，有20例为无感染触发AE-IIP。叠加在IIPs上的肺炎的生存时间明显长于任何AE-IIPs。细菌性肺炎叠加在CF-IIP上的生存时间比AE-IIP的生存时间长得多（对于每个特发性和所有触发的IIP）。此后，感染触发的生存时间明显长于特发性或非感染触发的AE-IIP。感染触发的AE-IIP的死亡率显着低于其他类型的AE-IIP。此外，冬季感染触发的AE-IIPs的发生率明显高于其他季节。此外，临床AE-IIPs类型和AE-IIP发作时的放射学发现是AE-IIPs诱发的早期死亡的重要危险因素。