Active surveillance cultures for multidrug-resistant Gram-negative organisms in the intensive care unit: is it necessary to conduct them weekly?

Abstract

Aim: Multidrug-resistant Gram-negative bacteria (MDR-GNB) pose a major threat to public health due to the limited treatment options and their frequent association with healthcare-associated infections. Active surveillance culture (ASC), a component of infection prevention strategies, remains controversial. This study evaluated the effectiveness of ASC performed weekly versus only upon ICU admission and discharge for detecting MDR-GNB.

Materials and methods: In a prospective study, two monitoring strategies were compared over a period of 18 months in six intensive care units. Phase 1 involved conducting ASC weekly, while Phase 2 entailed conducting ASC exclusively at the time of ICU admission and discharge.

Results: A total of 233 MDR-GNB infections were documented: 130 (11.38/1,000 patient-days) in Phase 1 and 103 (8.47/1,000 patient-days) in Phase 2. This reflects a statistically significant decrease in infection rates in Phase 2 (IRR: 1.34; 95% CI: 1.04-1.74). No significant differences were observed in species-specific infection rates between the two phases.

Conclusions: Reducing ASC frequency from weekly to only ICU admission and discharge did not increase MDR-GNB infection rates. The implementation of comprehensive infection prevention and control measures proved sufficient for the management of bacterial infections.