City or Suburb, Resistance Flows: Wastewater-Borne ESKAPE and AMR Genes in Malaysian Hospitals.

BACKGROUND/OBJECTIVES: Hospital wastewater has become a major hotspot for the spread of antimicrobial resistance and the accumulation of antibiotic-resistant genes. We focused on ESKAPE pathogens isolated from hospital wastewater and their antibiotic profiles, which are known to cause nosocomial infections in hospitals. Screening for antibiotic resistant genes in isolates and quantifying antibiotic residues in hospital wastewaters, which may reflect the amount of usage of antibiotics in Klang Valley city hospitals in Malaysia. METHODS: Hospital wastewater treatment plants from Klang Valley city were selected based on the study criteria. ESKAPE pathogens were isolated and identified using 16S rRNA PCR, and antibiotic sensitivity testing was performed. Antibiotic resistant gene screenings were performed using quantitative PCR, and quantification of antibiotic residues in the effluent samples was performed using liquid chromatography-mass spectrometry (LC-MS). RESULTS: Klebsiella pneumoniae with Multiple Antibiotics Resistance Index (MARi) ranging from low (0.29) to very high resistance (0.71) dominantly isolated among ESKAPE pathogens followed by Enterococcus faecium ranging from low (0.29) to critical resistance (1.0) from hospital wastewater in Klang Valley city. The ermB gene was the predominant antibiotic resistance gene identified in Klang Valley city hospitals and suburban hospitals, representing 45.5% of isolated E. faecium from suburban hospitals and 69% from city hospitals. Although the detection of antibiotic residues was minimal, vancomycin and ciprofloxacin were detected from the wastewater. CONCLUSIONS: These findings call for improved wastewater management and antibiotic stewardship to mitigate the spread of resistant pathogens from healthcare facilities into the environment.