Navigating an Evolving Microbial Landscape: Emerging Antimicrobial Resistance Trends and Precision Stewardship in Tianjin Tertiary Hospitals (2021-2023)

Yong-Li Wan¹Tao Han²Qiang Sun³Dong-Hao Wang²Jun Li^1*Li-Jie Wang⁴Min Peng⁵Yin Li⁶Qing-Guo Feng⁷Chun-Guang Liu⁸Jie Xu⁹Bin Bao¹⁰Mei Su¹¹Zhi-Yong Fei¹²Xu-Liang Wang¹³Xiao-Bo Liu¹⁴

• ¹Chu Hsien-I Memorial Hospital, Tianjin Medical University, Tianjin, China
• ²Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
• ³Tianjin Union Medical Center, Tianjin, China
• ⁴First Teaching Hospital of Tianjin University of Traditionnl Chinese Medicine, Tianjin, China
• ⁵Tianjin Medical University General Hospital, Tianjin, China
• ⁶Tianjin First Center Hospital, Tianjin, China
• ⁷Tianjin Fifth Central Hospital, Tianjin, China
• ⁸Tianjin Baodi Hospital, Tianjin, China
• ⁹TEDA Hospital, Tianjin, China
• ¹⁰Tianjin Xiqing Hospital, Tianjin, China
• ¹¹Tianjin Hongqiao Hospital, Tianjin, China
• ¹²Haibin People's Hospital of Tianjin Binhai New Area, Tianjin, China
• ¹³Tianjin Jinnan Hospital, Tianjin, China
• ¹⁴PKUCare CNOOC Hospital, Tianjin, China

Objective: To evaluate microbial distribution and antimicrobial resistance (AMR) patterns in clinical isolates from 13 tertiary hospitals and one secondary hospital in Tianjin (2021–2023) to inform precision-driven antimicrobial stewardship and infection control interventions. Methods: In this retrospective, multicenter study, we collected routine diagnostic specimens—including sputum, fecal samples, secretions, blood, and drainage fluids. Data were processed per standardized protocols (CARSS, CHINET) and interpreted using current CLSI-M100 breakpoints. Statistical analyses were performed with SPSS 20.0 (significance set at two‐tailed P < 0.05). Results: Sputum specimens increased from 39.1% to 43.0%, while urine samples and secretions declined. Klebsiella pneumoniae prevalence rose from 18.3% to 20.3%, whereas Escherichia coli remained stable. E. coli maintained excellent susceptibility to carbapenems and amikacin (≤2% resistance); notably, ceftazidime/avibactam resistance declined from 7.2% to 3.4% (P = 0.005) amid a significant increase in cefepime resistance (24.4% to 29.6%, P < 0.001). K. pneumoniae exhibited parallel trends, with escalating resistance to β-lactam/β-lactamase inhibitor agents. In Pseudomonas aeruginosa, aminoglycoside, and carbapenem profiles remained stable, while ceftazidime/avibactam sensitivity markedly improved, suggesting shifts in underlying resistance mechanisms. Acinetobacter baumannii showed enhanced susceptibility to aminoglycosides, β-lactam inhibitors, and fluoroquinolones; however, carbapenem-resistant isolates continued to exhibit near-universal resistance. Among gram-positive pathogens, methicillin-resistant Staphylococcus aureus sustained near-universal β-lactam resistance with improved rifampicin sensitivity, while glycopeptides and linezolid remained fully active. Enterococcus faecalis demonstrated reduced ampicillin resistance, contrasting with E. faecium’s near-pan-resistance to β-lactams and fluoroquinolones. Conclusion: Evolving, species-specific AMR patterns in Tianjin hospitals highlight the urgent need for real-time, regionally stratified surveillance and molecularly informed stewardship strategies to guide targeted antimicrobial interventions and improve clinical outcomes.