Abstract: Objective To analyze the clinical complications of patients with influenza pneumonia in different PDCD5 levels and the risk factors of severe influenza patients. Methods 104 patients with influenza treated in our hospital from June 2020 to December 2020 were divided into HP group(PDCD5>10 μg/L, n=38)and LP group(PDCD5≤10 μg/L, n=66). They were divided into mild disease group(n=61)and severe disease group(n=43)according to the severity. The incidence of respiratory failure, cardiac myositis and multiple organ failure(MODS)were analyzed. The general and clinical data of the two groups were compared, and the independent risk factors of severe patients were analyzed with multivariate logistic regression. Results The incidence of respiratory failure, myocarditis and MODS in HP group were higher than those in LP group(P<0.05). Univariate analysis showed that there were significant differences between severe group and mild group in BMI, smoking history, COPD, MMP9, PaO₂/FiO₂, lymphocyte, lymphocyte subsets and PDCD5 level(P<0.05). Multivariate logistic regression analysis showed that low lymphocyte and CD4⁺T cell, high PCT and PDCD5>10 μg/L were independent risk factors for patients with severe influenza(P<0.05). Conclusion Lymphocytes, CD4⁺T lymphocytes, PDCD5 and PCT may affect the disease progression and more attention should be paid to those indexes.

Key words: influenza, programmed cell death molecule 5, lymphocyte subsets, procalcitonin