Contribution of acquired meticillin-resistant Staphylococcus aureus bacteraemia to overall mortality in a general...

Area of Science:

• Infectious Diseases
• Critical Care Medicine
• Epidemiology

Background:

• Meticillin-resistant Staphylococcus aureus (MRSA) is a significant cause of hospital-acquired infections.
• Intensive care unit (ICU) patients, particularly those with prolonged stays, are at higher risk for healthcare-associated infections like MRSA bacteraemia.

Purpose of the Study:

• To determine the incidence and impact of MRSA bacteraemia acquired in the ICU.
• To assess the attributable mortality associated with ICU-acquired MRSA bacteraemia.
• To evaluate the relationship between length of stay and MRSA bacteraemia incidence.

Main Methods:

• Retrospective analysis of 77 patients with MRSA bacteraemia occurring >= 5 days post-ICU admission over 11 years.
• Case-control study matching MRSA bacteraemia patients with uninfected controls based on diagnosis and APACHE II score.
• Calculation of incidence rates, mortality, relative risk, and attributable mortality.

Main Results:

• MRSA bacteraemia acquired >= 5 days post-ICU admission occurred in 77 patients.
• The overall mortality for these 77 patients was 57.1%.
• MRSA bacteraemia was associated with a significantly higher mortality (53.6%) compared to matched controls (31.8%), indicating an additional absolute mortality of 21.8%.

Conclusions:

• ICU-acquired MRSA bacteraemia significantly increases patient mortality.
• Preventing initial MRSA colonization and infection in long-stay ICU patients is essential.
• The incidence of MRSA bacteraemia rises with increased length of ICU stay.