Risk Factors for 30-Day Mortality in Patients with Bacteremic Pneumonia Caused by Escherichia coli and Klebsiella pneumoniae: A Retrospective Study

Abstract

Chuwen Zhao,1,2,* Yunwei Zheng,1,* Yaping Hang,1 Yanhui Chen,1 Yanhua Liu,1 Junqi Zhu,1,2 Youling Fang,1,2 Jianqiu Xiong,3 Longhua Hu1 1Department of Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China; 2School of Public Health, Nanchang University, Nanchang, Jiangxi, People’s Republic of China; 3Department of Nursing, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China*These authors contributed equally to this workCorrespondence: Longhua Hu, Department of Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Mingde Road No. 1, Nanchang, Jiangxi, 330006, People’s Republic of China, Email [email protected] Jianqiu Xiong, Department of Nursing, the Second Affiliated Hospital of Nanchang University, Mingde Road No. 1, Nanchang, Jiangxi, 330006, People’s Republic of China, Email [email protected]: Escherichia coli and Klebsiella pneumoniae are prevalent Gram-negative microorganisms responsible for pneumonia, as well as the primary Enterobacteriaceae pathogens causing bacteremic pneumonia. The objective of this research is to analyze the risk factors associated with bacteremic pneumonia caused by these pathogens and develop a predictive model.Patients and Methods: This retrospective investigation encompassed a cohort of 252 patients diagnosed with Escherichia coli or Klebsiella pneumoniae-induced bacteremic pneumonia between 2018 and 2022. The primary endpoint was 30-day mortality, which was analyzed using multifactorial logistic regression, nomogram construction, and Bootstrap validation.Results: Among the 252 patients diagnosed with Escherichia coli and Klebsiella pneumoniae, 65 succumbed to the disease while 187 survived. The overall 30-day mortality was found to be 25.8%. A multifactorial logistic regression analysis revealed that diastolic blood pressure, cerebrovascular diseases/transient ischemic attacks (TIA), immunosuppression, blood urea nitrogen, Pitt score, and CURB-65 score were statistically significant factors. The Nomogram model demonstrated an AUC of 0.954, which closely aligns with the Bootstrap-derived mean AUC of 0.953 (95% CI: 0.952– 0.954).Conclusion: In patients with bacteremic pneumonia caused by Escherichia coli and Klebsiella pneumoniae, Low diastolic blood pressure (≤ 61 mmHg), pre-existing cerebrovascular disease/ transient ischemic attacks (TIA), immunosuppression status, elevated blood urea nitrogen levels (≥ 8.39 mmol/L), high Pitt score (≥ 3), and a high CURB-65 score (≥ 2) are all independent risk factors for Escherichia coli and Klebsiella pneumoniae bacteremic pneumonia, among which the first three warrant particular attention.Keywords: Klebsiella pneumoniae, Escherichia coli, bacteremic pneumonia, 30-day mortality, nomogram

Keywords

• klebsiella pneumoniae
• escherichia coli
• bacteremic pneumonia
• 30-day mortality
• nomogram.