Usefulness of procalcitonin for diagnosing complicating sepsis in patients with cardiogenic shock.

OBJECTIVE: Patients in cardiogenic shock (CS) often present with signs of systemic inflammation that mimic infection, especially in the setting of multiple organ failure (MOF). To clarify the usefulness of procalcitonin (PCT) for diagnosing complicating sepsis in patients with CS, especially in the presence of MOF we compared PCT concentrations in patients with CS with and without MOF to those in patients with septic shock (SS).

DESIGN AND SETTING: Retrospective analysis in the cardiovascular ICU at a university hospital.

PATIENTS: 40 patients with CS, 15 patients with SS, and 11 noncritically ill patients without infection.

MEASUREMENTS AND RESULTS: Infection was excluded by clinical and microbiological examination in all CS patients at the time of blood sampling. Nevertheless 35% exhibited CRP concentrations higher than 10 mg/dl and 25% PCT concentrations higher than 2 ng/ml. Median PCT concentrations were higher in CS patients than in controls but lower than in patients with SS. CS patients with MOF at the time of blood sampling exhibited higher PCT concentrations than patients without organ failure. In the pooled population of patients with CS and SS PCT had a higher area under the receiver operating characteristic curve (0.86 vs. 0.83) than CRP and a PCT concentration of 10 ng/ml or higher had greater specificity for sepsis than a PCT concentration of 2 ng/ml or higher but lower negative predictive value.

CONCLUSIONS: PCT concentrations above 2 ng/ml are frequently found in CS patients with MOF and do not necessarily indicate infection. PCT was slightly better than CRP for diagnosing sepsis in our study, but a PCT concentration of 10 ng/ml or higher seems to be more appropriate for diagnosing this complication in CS patients than 2 ng/ml.