Istituti Clinici Scientifici Maugeri IRCCS, Pavia, Italy.
Division of Pneumology, Department of Medical Sciences, University Hospital "San Giovanni di Dio e Ruggi d'Aragona", Salerno, Italy.
Respir Med. 2022 Mar;193:106745. doi: 10.1016/j.rmed.2022.106745. Epub 2022 Jan 26.
The nature of the inflammatory and fibrotic processes found in patients with post-COVID-19 syndrome makes it possible to speculate that in such patients fractional exhaled nitric oxide (FeNO) may be a useful biomarker. Consequently, we set out to verify the consistency of this hypothesis. We consecutively enrolled 68 post-COVID patients after being hospitalized for persistent clinical manifestations within 2 months from disease onset and 29 healthy volunteers as control group. None of post-COVID patients had bronchial asthma or were being treated with a corticosteroid. Only 19 out of 68 post-COVID-19 patients reported a FeNO value > 25 ppb. The mean FeNO value in post-COVID-19 patients was 18.55 ppb (95% CI: 15.50 to 21.58), while in healthy subjects it was 17.46 ppb (95% CI: 15.75 to 19.17). The mean difference was not statistically significant (P = 0.053). However, the mean FeNO value of post-COVID-19 patients was higher in men than in women (20.97 ppb; 95% CI: 16.61 to 25.33 vs 14.36 ppb; 95% CI: 11.11 to 17.61) with a difference between the two sexes that was statistically significant (P = 0.016). Mean FeNO was 14.89 ppb (95% CI: 10.90 to 18.89) in patients who had been treated with systemic corticosteroids because of their COVID-19, and 20.80 ppb (95% CI: 16.56 to 25.04) in those who had not taken them, with a difference that was statistically significant (P = 0.043). The data generated in this study suggest that measurement of FeNO is not useful as a biomarker in post-COVID-19 patient. However, this hypothesis needs solid validation with additional specifically designed studies.
研究表明，新冠病毒感染后综合征患者体内存在炎症和纤维化过程，推测呼出气一氧化氮（FeNO）分数可能是有用的生物标志物。因此，我们开始验证这一假说。我们连续招募了 68 例新冠病毒感染后住院的患者，这些患者在发病后 2 个月内仍有持续的临床症状，同时招募了 29 例健康志愿者作为对照组。所有新冠病毒感染后患者均无支气管哮喘病史，且未接受皮质类固醇治疗。仅有 19 例新冠病毒感染后患者的 FeNO 值>25 ppb。新冠病毒感染后患者的平均 FeNO 值为 18.55 ppb（95%可信区间：15.50 至 21.58），而健康对照组的平均 FeNO 值为 17.46 ppb（95%可信区间：15.75 至 19.17）。两组间平均差异无统计学意义（P=0.053）。然而，新冠病毒感染后患者的平均 FeNO 值男性高于女性（男性 20.97 ppb；95%可信区间：16.61 至 25.33 vs 女性 14.36 ppb；95%可信区间：11.11 至 17.61），且男女间差异有统计学意义（P=0.016）。因新冠病毒而接受全身皮质类固醇治疗的患者的平均 FeNO 值为 14.89 ppb（95%可信区间：10.90 至 18.89），未接受皮质类固醇治疗的患者的平均 FeNO 值为 20.80 ppb（95%可信区间：16.56 至 25.04），两组间差异有统计学意义（P=0.043）。本研究的数据表明，FeNO 测量在新冠病毒感染后患者中作为生物标志物并不有用。然而，这一假说需要通过额外的专门设计的研究进行扎实的验证。
