The importance of pathogens in sepsis: Staphylococcus aureus story.

Different pathogens cause different outcomes for patients with sepsis. They influence intensive care unit (ICU) mortality, ICU length of stay (ICU LOS) and the need for mechanical ventilation (MV). We undertook a retrospective data-based analysis over a 6-y period. Seventy-eight patients with methicillin-sensitive Staphylococcus aureus (MSSA) and 74 patients with Escherichia coli (EC) sepsis were included in the study. ICU mortality for the MSSA group was 32 (41.0%) vs 26 (35.1%) for the EC group (p = 0.506; OR 1.28, 95% CI 0.67-2.48). There was no significant difference in ICU LOS (MSSA group: median 7.5, interquartile range (IQR) 4-14 days and EC: median 5, IQR 3-13.5 days; p = 0.214). Need for MV in the MSSA group was present in 45 (57.7%) patients vs 43 (58.1%) in the EC group. Univariate analysis did not show that MSSA was independently associated with ICU mortality (p = 0.506). Logistic regression analysis showed that after adjustment for APACHE II, the chance of ICU death doubled in the MSSA group (odds ratio 2.166; 95% confidence interval 1.004-4.858). The odds for ICU admission were 8 times higher in MSSA patients. MSSA sepsis should be considered as an independent factor for ICU mortality after adjustment for APACHE II.