Investigation of pathogen resistance in Chinese cancer patients based on bacterial resistance surveillance in 23...

Infection is a common and often fatal complication in cancer patients. Notably, cancer patients account for up to 21% of all sepsis cases. Furthermore, sepsis is present in 30% of all deaths among those hospitalized with cancer. However, comprehensive antimicrobial resistance (AMR) surveillance data specific to this population are lacking. This gap hinders the effectiveness of antimicrobial stewardship programs (ASPs).

We investigated bacterial distribution and AMR patterns in Chinese cancer patients to inform empirical therapy and ASPs. This multicenter retrospective study collected hospital-wide clinical isolates and drug-susceptibility data from 23 cancer centers during 2016-2023. All procedures followed standardized methods in accordance with national surveillance protocols and Clinical and Laboratory Standards Institute guidelines. Data were subjected to dual validation using WHONET and a domestically developed big-data system.

Gram-negative 75.4% (270,609), Gram-positive 24.6% (88,177) of 358,786 isolates from cancer patients in these oncology centers. Predominant Gram-negative species were Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterobacter cloacae. Escherichia coli exhibited low imipenem resistance (0.9-1.5%) with a recent increase (2021-2023: APC = 16.57%, p < 0.001). Klebsiella pneumoniae showed stable imipenem resistance (1.6-1.9%) but increasing meropenem resistance (0.4-1.6%). Pseudomonas aeruginosa imipenem resistance declined (12.5-7.9%), while meropenem resistance remained stable (7.0-5.2%); while Acinetobacter baumannii carbapenem resistance increased substantially (imipenem: 9.6-18.4%; meropenem: 4.7-18.8%). Leading Gram-positive organisms were Staphylococcus epidermidis, Staphylococcus aureus, Enterococcus faecium, Enterococcus faecalis, and Staphylococcus haemolyticus. Methicillin-resistant Staphylococcus aureus (MRSA) resistance declined over five years, with no resistance to linezolid, vancomycin, or teicoplanin. Enterococcus spp. gradually developed resistance to last-resort antibiotics.

Carbapenem resistance among common Gram-negatives in cancer patients was below national averages. MRSA and enterococcal resistance were also below national levels. These findings underscore the unique resistance epidemiology in oncology, supporting tailored guidelines and dedicated surveillance.