Incidence and significance of a positive troponin test in bacteremic patients without acute coronary syndrome

BACKGROUND: Since the introduction of troponin for the diagnosis of myocardial infarction, several studies have shown additional conditions in which troponin is elevated, including sepsis. The objective of this study was to determine the incidence of an elevated troponin in patients with bacteremia and its significance. METHODS: This was a prospective, noninterventional study. Patients with a positive blood culture were included. Cardiac troponin I (cTnI) was determined within 4 days of blood culture. A repeat electrocardiogram was obtained in a sample of patients with elevated cTnI and in patients with a negative troponin test. Demographic, clinical, and microbiological data were obtained for all patients. RESULTS: A total of 159 bacteremic patients were included. Positive cTnI was detected in 69 patients (43%). Elevated cTnI was associated with a number of underlying diseases, hospitalization ward, severity of the systemic inflammatory condition, and kidney function (P<.05-.001). A repeat electrocardiogram was performed in 39 patients with a positive cTnI and in 28 patients with a negative cTnI. Two of 39 patients (5%) in the positive cTnI group had ischemic changes and 2 patients (5%) had nonspecific changes, whereas only 1 patient (4%) with a negative cTnI had nonspecific changes. Bivariate analysis revealed a statistically significant association for positive cTnI and mortality; however, on multivariate analysis this was no longer significant. CONCLUSION: Forty-three percent of bacteremic patients had an elevated cTnI. Risk factors for elevated cTnI were severity of the underlying infection, renal function, and underlying cardiac disease. Increased cTnI was found to be a dependent risk factor and a surrogate marker for death. (c) 2008 Elsevier Inc. All rights reserved.