Staphylococcus epidermidis infections linked to ICU septic shocks

Bloodstream infections caused by Staphylococcus epidermidis (SE-BSI) may lead to septic shock in patients admitted to intensive care unit (ICU), according to a study.

For the study, researchers looked at a retrospective cohort in two medical ICUs. SE-BSIs were defined as two or more independent SE-positive blood cultures of the same strain, identified within 48 hours and without concurrent infection.

Fifty-nine patients (median age 67 years, 58 percent men) were included in the analysis. The median Simplified Acute Physiology Score (SAPS) II was 59 points, and 33 patients (56 percent) were immunocompromised.

A total of 37 patients (63 percent) required norepinephrine initiation or increase at the onset of SE-BSI, while 22 (37 percent) did not require vasopressors.

Of note, patients who required norepinephrine initiation or increase had significantly greater concomitant arterial lactate levels (2.8 vs 1.5 mmol/L; p<0.01), lower mean blood pressure (49 vs 61 mm Hg; p=0.01), and higher mortality (46 percent vs 14 percent at day 28; p=0.01) compared with those who did not require vasopressors.

With regard to antibiotics, patients who required norepinephrine initiation or increase had lower susceptibility rates towards linezolid and vancomycin than those who did not require vasopressors (71 percent vs 100 percent).

At the time of SE-BSI, all but one patient had central venous access device, mostly inserted into the jugular vein.