Pathogenic characteristics of elderly patients with urinary tract infection / 中华传染病杂志

ABSTRACT

Objective:To analyze the pathogenic distribution characteristics of elderly inpatients with urinary tract infection (UTI).Methods:Retrospective analysis of the clinical data and pathogen detection of 809 patients with UTI aged ≥60 years admitted to The First Affiliated Hospital of China Medical University from January 2019 to January 2023 was performed.The differences in the pathogen distribution of patients with UTI were compared between groups of 60 to 79 years old and ≥80 years old. The chi-square test was used for statistical analysis.Multivariate logistic regression analysis was used to analyze the risk factors for bacterial production of extended spectrum β lactamase (ESBL).Results:A total of 914 strains of pathogens were isolated from 809 patients, including 584 strains isolated from 60 to 79 years old patients, 330 strains isolated from ≥80 years old patients, and 62 patients had mixed infections with bacteria and fungi. In the group of patients ≥80 years old, there were 144(43.64%) Gram-negative bacteria. Escherichia coli (16.67%(55/330)), Klebsiella pneumoniae (9.70%(32/330)) and Proteus mirabilis (3.03%(10/330)) were the main members in Enterobacteriaceae. Pseudomonas aeruginosa (5.76%(19/330)) and Acinetobacter baumannii (4.55%(15/330)) were main members of non-fermentive bacteria. There were 104 strains (31.52%) of Gram-positive bacteria detected in the group of patients ≥80 years old, mainly Enterococcus faecium (21.21%(70/330)), and 63 strains (19.09%) of fungi were detected, mainly Candida albicans (9.09%(30/330)). Compared with the group of 60 to 79 years old, the detection rate of Escherichia coli was lower ( χ2=35.78, P<0.001), but Enterococcus faecium ( χ2=4.91, P=0.027) and fungi ( χ2=10.03, P=0.002) were higher in the group of patients ≥80 years old. Among the 375 strains of Enterobacteriaceae, 190 strains (50.67%) were ESBL positive, including 127 strains of Escherichia coli, 46 strains of Klebsiella pneumoniae and 17 strains of Proteus mirabilis. Multivariate logistic analysis found that the use of antibiotic before hospitalization (odds ratio ( OR)=18.528, 95% confidence interval (95% CI) 3.893 to 88.171, P<0.001), complicated with pulmonary infection ( OR=4.182, 95% CI 1.387 to 12.611, P=0.011) were independent risk factors for bacterial production of ESBL. Conclusions:The pathogens of elderly patients (aged≥80 years old) with UTI are mainly Gram-negative bacteria, and the detection rates of Enterococcus and fungi are also high. A considerable number of patients have mixed bacterial and fungal infections. The use of antibiotic before hospitalization and complicated with pulmonary infection are independent risk factors for bacterial production of ESBL.