Increased plasma levels of soluble triggering receptor expressed on myeloid cells 1 and procalcitonin after cardiac surgery and cardiac arrest without infection

Soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) and procalcitonin (PCT) are often considered to be specific markers for infection. We evaluated plasma levels of sTREM-1 and PCT in patients with systemic inflammatory response syndrome but no sepsis. Noninfected patients undergoing elective heart surgery with cardiopulmonary bypass (n = 76) and patients admitted after out-of-hospital cardiac arrest (n = 54) were followed up for 3 days. Patients with severe sepsis (n = 55) and healthy volunteers (n = 31) were included as positive and negative controls, respectively. Plasma levels of PCT were higher in sepsis patients than in patients who survived after cardiac arrest or after heart surgery. In contrast, peak plasma levels of sTREM-1 in heart surgery and in cardiac arrest patients overlapped with those measured in patients with sepsis. Both sTREM-1 and PCT were significantly higher in cardiac arrest patients who died of refractory shock than in those who died of neurological failure or survived without major neurological damage. In the cardiac arrest patients with refractory shock, sTREM-1 and PCT levels were similar to those in the patients with severe sepsis. In conclusion, sTREM-1 and PCT are not specific for infection and can increase markedly in acute inflammation without infection.