Critical cases of coronavirus disease 2019 (COVID‐19) are associated with a high risk of mortality. It remains unclear why patients with the same critical condition have different outcomes. We aimed to explore relevant factors that may affect the prognosis of critical COVID‐19 patients. Six critical COVID‐19 inpatients were included in our study. The six patients were divided into two groups based on whether they had a good or poor prognosis. We collected peripheral blood samples at admission and the time point of exacerbation to compare differences in the phenotypes and functions of major populations of immune cells between the groups. On admission, compared to patients with poor prognoses, those with good prognoses had significantly higher counts of monocytes (P < .05), macrophages (P < .05), higher frequency of CD3⁺CD4⁺CD45RO⁺CXCR3⁺ subsets (P < .05), higher frequency of CD14⁺CD11C⁺HLA‐DR⁺ subset of dendritic cells (P < .05), and a lower count of neutrophils (P < .05). At the time point of exacerbation, the proportions of naïve CD4⁺ T cells (P < .05), Tregs, and Th2 cells in the poor prognosis group were relatively higher than those in the good prognosis group, and CD4⁺ memory T cells were relatively lower (P < .05). According to our results, the poor prognosis group showed a worse immune response than the good prognosis group at the time of admission and at exacerbation. Dysregulation of the immune response affects the outcome of critical COVID‐19 patients.

中文翻译：

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免疫反应失调会影响危重 COVID-19 患者的预后。


2019 年冠状病毒病 (COVID-19) 危重病例与高死亡风险相关。目前尚不清楚为什么相同危重的患者会有不同的结果。我们的目的是探讨可能影响危重COVID-19患者预后的相关因素。我们的研究纳入了 6 名危重 COVID-19 住院患者。根据预后良好或不良，这六名患者被分为两组。我们在入院时和恶化时间点收集了外周血样本，以比较各组之间主要免疫细胞群的表型和功能的差异。入院时，与预后不良的患者相比，预后良好的患者的单核细胞计数 ( P < .05)、巨噬细胞计数 ( P < .05) 显着更高，CD3 ⁺ CD4 ⁺ CD45RO ⁺ CXCR3 ⁺亚群的频率更高 ( P < .05)，CD14 ⁺ CD11C ⁺ HLA-DR ⁺树突细胞亚群的频率较高 ( P < .05)，中性粒细胞计数较低 ( P < .05)。恶化时点，预后不良组中naïve CD4 ⁺ T细胞（ P < .05）、Tregs、Th2细胞比例相对高于预后良好组，CD4 ⁺记忆T细胞比例相对较高相对较低 ( P < .05)。根据我们的结果，预后不良组在入院时和病情恶化时表现出比预后良好组更差的免疫反应。免疫反应失调会影响危重 COVID-19 患者的预后。