OBJECTIVE To investigate the clinical characteristics of carbapenem-resistant Pseudomonas aeruginosa （CRPA） infections in elderly patients and summarize their risk factors.

METHODS Clinical data of 282 elderly inpatients with P. aeruginosa infections treated at Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from Jan. 2023 to Dec. 2023 were retrospectively collected. The patients were divided into a resistant group （n=50） and a susceptible group （n=232） based on the presence or absence of carbapenem resistance. The clinical characteristics of CRPA infections were analyzed, and multivariate logistic regression was employed to identify risk factors for hospital-associated CRPA infections in elderly patients.

RESULTS Among the 282 specimens, 50 CRPA strains were detected, with a detection rate of 17.73%. CRPA was predominantly found in the surgical ICU （30.00%） and mainly isolated from respiratory tract specimens. CRPA exhibited high resistance rates to antimicrobial agents, with the highest resistance observed against imipenem （94.00%, 47/50）. Comorbid neurological diseases （OR=3.087）, history of fluoroquinolone use （OR=2.493） and history of carbapenem use （OR=2.790） were identified as risk factors for CRPA infections in elderly patients （P＜0.05）.

CONCLUSIONS Comorbid neurological diseases, history of fluoroquinolone use and carbapenem use are risk factors for CRPA infections in elderly patients. Increased attention should be given to patients with these risk factors.