Abstract: Objective To investigate the clinical efficacy of spleen polypeptide injection combined with imipenem and cilastatin sodium in the treatment of severe community acquired pneumonia (SCAP) and the effects on the levels of C-reactive protein (CRP), interleukin (IL)-6, IL-8 and T lymphocyte subpopulation in the elderly patients. Methods From January 2018 to January 2020, a total of 92 elderly patients with SCAP were randomly divided into the observation group and the control group, with 46 cases in each group. The control group was treated with imipenem and cilastatin sodium, and the observation group was treated with spleen polypeptide injection on the basis of the control group for 14 days. The levels of CRP, IL-6, IL-8 and T lymphocyte subpopulation (CD3⁺, CD4⁺, CD4⁺/CD8⁺) and APACHE Ⅱ scores of the two groups were compared before and after treatment. The clinical effects and the length of stay, 28-day mortality and adverse rections were recorded. Results The total effective rate of the observation group was 95.7% (44/46), which was significantly higher than that of the control group (80.4%, 37/46)(P<0.05). After treatment, the levels of CRP, IL-6 and IL-8 were significantly lower, the levels of CD3⁺, CD4⁺ and CD4⁺/CD8⁺ in peripheral blood were significantly higher, and the scores of APACHE Ⅱ were significantly decreased in both groups, especially in the observation group (P<0.05). Compared with the control group, the length of hospitalization in the observation group was significantly shorter (P<0.05). There was no significant difference in 28-day mortality and the rate of adverse reactions between the two groups (P>0.05). Conclusions Spleen polypeptide injection combined with imipenem and cilastatin sodium has a satisfactory overall efficacy in the treatment of the elderly patients with SCAP. The mechanism may be related with down-regulating CRP, IL-6 and IL-8 in vivo and maintaining the balance and stability of T lymphocyte subpopulation in peripheral blood.

Key words: severe community-acquired pneumonia, aged, imipenem and cilastatin sodium, spleen polypeptide injection, inflammatory factor, immune function