Spatial distribution and co-detection of antimicrobial resistance genes and ESKAPEE pathogens in hospital sink environments

Background Hospital sink environments are potential reservoirs for antimicrobial resistance genes and opportunistic pathogens yet their spatial distribution and co-detection patterns remain incompletely characterized. Methods A total of 216 environmental swab samples were collected from six predefined locations (the bottom of the basin, the inner wall of the faucet, the faucet, and 0.5 m, 1.0 m, and 2.0 m from the basin) across four hospital wards (respiratory ward, ICU ward, burn ward, and infection ward). All samples were analyzed using multiplex nucleic acid mass spectrometry to simultaneously detect 23 targets, encompassing six major antibiotic resistance gene classes and extended ESKAPEE pathogen groups. Results Among 216 samples (54 per ward), bla TEM exhibited the highest detection rate (88.9–100%), followed by bla VIM (>75% at all locations). P. aeruginosa and Enterobacter were the most prevalent pathogens (detection rates: 35.2-74.1% and 40.7-74.1%, respectively). Several targets showed significant spatial enrichment after FDR adjustment, including bla SHV , KP-bla KPC , EA-bla KPC , bla NDM-5 , and mecA . After Benjamini-Hochberg FDR correction, no co-detection pair reached statistical significance; the strongest signals before correction were bla TEM -E. cloacae (50.5%) and bla SHV -P. aeruginosa (16.2%). ESBL genes showed significantly higher mean detection ratios at sink-proximal locations than at distal locations ( p < 0.001). Conclusions Antimicrobial resistance genes and ESKAPEE pathogens are widely distributed in hospital sink environments, with a sink-proximal enrichment and a spatial gradient across sampling locations. Although no co-detection pair remained significant after FDR correction, the strongest signals ( bla TEM – E. cloacae and bla SHV – P. aeruginosa ) may warrant further investigation in larger studies. These findings provide spatially resolved evidence for identifying high-risk loci (the inner wall of the faucet) to support targeted infection control interventions in high-acuity wards.