Background: Characterization of reticulo-endothelial activation in COVID-19 may guide treatment. Objectives: To assess reticulo-endothelial activation and its correlation with disease severity and death in patients across the entire spectrum of COVID-19 severity. Methods: Consecutive hospitalized COVID-19 patients were studied, with similar number of patients in each disease severity category. Baseline serum ferritin, sCD163 (macrophage activation markers) and plasma von Willebrand factor (VWF) antigen (endothelial activation marker) levels were studied. Clinical parameters and plasma D-dimer levels were also studied. The study parameters were correlated with COVID-19 severity and survival. Results: The 143 patients (104 males [80%], age 54 [42 – 65] years, median [inter-quartile range]) presented 4 (3—7) days after symptom onset. Thirty-four patients had mild disease, 36 had moderate disease, 36 had severe disease and 37 had critical disease at baseline. With increasing COVID-19 severity, ferritin, sCD163, VWF and D-dimer levels significantly increased at baseline, however, 139 patients had normal sCD163 levels. Of the reticulo-endothelial markers, VWF level independently correlated with COVID-19 severity and with survival. VWF level > 332.6 units/dl correlated with COVID-19 severity (odds ratio [OR]: 2.77 [95% confidence interval (C.I): 1.1 – 6.99], p value: 0.031) and in-hospital death (OR [95% CI]: 29.28 [5.2 – 165], p value < 0.001). Conclusions: Reticulo-endothelial activation markers increased incrementally with worsening COVID-19 severity. Baseline endothelial activation marker (VWF), and not macrophage activation markers, independently correlated with COVID-19 severity and death.

背景：COVID-19 中网状内皮细胞活化的特征可以指导治疗。目的：评估整个​​ COVID-19 严重程度患者的网状内皮细胞活化及其与疾病严重程度和死亡的相关性。方法：对连续住院的 COVID-19 患者进行了研究，每个疾病严重程度类别中的患者数量相似。研究了基线血清铁蛋白、sCD163（巨噬细胞活化标志物）和血浆血管性血友病因子（VWF）抗原（内皮活化标志物）水平。还研究了临床参数和血浆 D-二聚体水平。研究参数与 COVID-19 的严重程度和生存率相关。结果：143 名患者（104 种情况 [80%]，年龄 54 [42-65] 岁，中位数 [四分位距]）在症状发作后 4 (3-7) 天出现。在基线时，34 名患者患有轻度疾病，36 名患有中度疾病，36 名患有严重疾病，37 名患有危重疾病。随着 COVID-19 严重程度的增加，铁蛋白、sCD163、VWF 和 D-二聚体水平在基线时显着增加，然而，139 名患者的 sCD163 水平正常。在网状内皮标志物中，VWF 水平与 COVID-19 严重程度和生存率独立相关。VWF 水平 > 332.6 单位/dl 与 COVID-19 严重程度相关（优势比 [OR]：2.77 [95% 置信区间 (CI)：1.1 – 6.99]，p 值：0.031）和院内死亡（OR [95% CI]：29.28 [5.2 - 165]，139 名患者的 sCD163 水平正常。在网状内皮标志物中，VWF 水平与 COVID-19 严重程度和生存率独立相关。VWF 水平 > 332.6 单位/dl 与 COVID-19 严重程度相关（优势比 [OR]：2.77 [95% 置信区间 (CI)：1.1 – 6.99]，p 值：0.031）和院内死亡（OR [95% CI]：29.28 [5.2 - 165]，139 名患者的 sCD163 水平正常。在网状内皮标志物中，VWF 水平与 COVID-19 严重程度和生存率独立相关。VWF 水平 > 332.6 单位/dl 与 COVID-19 严重程度相关（优势比 [OR]：2.77 [95% 置信区间 (CI)：1.1 – 6.99]，p 值：0.031）和院内死亡（OR [95% CI]：29.28 [5.2 - 165]，p值 < 0.001)。结论：随着 COVID-19 严重程度的恶化，网状内皮细胞激活标志物逐渐增加。基线内皮活化标志物 (VWF)，而非巨噬细胞活化标志物，与 COVID-19 的严重程度和死亡独立相关。