Pathogen Distribution in Pulmonary Infection in Chinese Patients with Lung Cancer: a Systematic Review and Meta-analysis

Background: The immunity of patients with lung cancer decreases after treatment; thus, they are easily infected with pathogenic bacteria that causes pulmonary infections. Understanding the distribution characteristics of pathogenic bacteria in pulmonary infection in patients with lung cancer after treatment can provide a basis to effectively prevent infection and rationally use antibacterial drugs. However, no meta-analyses have assessed the distribution characteristics of pathogenic bacteria in mainland China. Therefore, our meta-analysis aimed to investigate the pathogen distribution in pulmonary infection in Chinese patients with lung cancer.

Methods: A literature search was conducted to study the pathogen distribution in pulmonary infection in Chinese patients with lung cancer between January 1, 2020 and December 31, 2022, using English and Chinese databases. The relevant data were extracted. The meta-analysis was performed using a random-effects model ( I > 50%) with 95% confidence intervals for forest plots. Data were processed using RevMan 5.3.

Results: Fifteen studies (2,683 strains in 2,129 patients with pulmonary infection were cultured) met the evaluation criteria. The results showed that Gram-negative bacteria had the highest detection rate (63%), followed by Gram-positive bacteria (23%), and fungi (12%). Among the Gram-negative bacteria detected, the distribution of the main pathogenic bacteria was Klebsiella pneumonia (17%), Pseudomonas aeruginosa (14%), Escherichia coli (13%), Acinetobacter baumannii (7%), Enterobacter cloacae (4%), and Hemophilus influenza (4%). Moreover, the prevalence of pulmonary infections after chemotherapy (53%) was significantly higher than that after surgery (10%), P < 0.05.

Conclusions: The prevalence of pulmonary infections after treatment, especially after chemotherapy, is high in Chinese patients with lung cancer, and Gram-negative bacteria are the predominant pathogens. Further studies are needed to monitor the prevalence of pulmonary infections and pathogen distribution in lung cancer patients in mainland China.