Abstract:【Abstract】 Objective To investigate the clinical efficacy of cefoperazone/sulbactam combined with moxifloxacin in the treatment of COPD complicated with acute lower respiratory tract infection and the effects of serum PCT and CRP levels.Methods We retrospectively analyzed the clinical data of 198 patients with COPD complicated with acute lower respiratory tract infection admitted to The Fifth People's Hospital of Chengdu hospital from January 2017 to February 2018. According to the different dosing regimens, they were divided into observation group and control group (99 cases each). The control group was given a single cefoperazone/sulbactam treatment and the observation group was given cefoperazone/sulbactam combined with moxifloxacin. After a single cefoperazone/sulbactam treatment, the observation group was treated with cefoperazone/sulbactam and moxifloxacin. The therapeutic efficacy, antibacterial efficacy, incidence of adverse reactions, and levels of PCT, CRP, WBC, IL6, CD8+, CD4+/CD8+, and CD3+ before and after treatment were compared between the two groups of patients. Results The total effective rate of treatment in the observation group (8990%) was higher than that of the control group (7677%) (P=0013). After treatment, serum PCT, CRP, WBC, and IL6 levels in both groups were lower than before treatment (P<005). The level of each inflammatory index in the observation group was lower than that in the control group (P<005). After treatment, the levels of CD4+/CD8+ and CD3+ in both groups were higher than before treatment, and the levels of CD8+ were lower than before treatment (P<005). The level of CD4+/CD8+ and CD3+ in the observation group was higher than that in the control group, and the level of CD8+ was lower in the observation group than in the control group (P<005). The bacterial clearance rate of the observation group (9358%) was higher than that of the control group (8468%) (χ2=4475, P=0034). There was no significant difference between the two groups in the total incidence of adverse reactions [(606%)VS (404%)](χ2=0421, P=0516).Conclusion Cefoperazone/sulbactam combined with moxifloxacin has significant clinical efficacy and antibacterial effect on patients with COPD complicated with acute lower respiratory tract infection. It can effectively inhibit serum PCT and CRP levels and improve immune function, and it is safe and reliable.