Procalcitonin-based indication of bacterial infection identifies high risk acute heart failure patients

Bacterial infections in patients hospitalized with acute heart failure are related to worse prognosis, but they can be difficult to diagnose. In this study we evaluated the prevalence, clinical correlates and association with outcomes of significantly elevated procalcitonin levels in patients hospitalized for acute heart failure without clear signs of bacterial infection.

1781 patients from the PROTECT trial were included. Patients with a body temperature >38°C, sepsis or active infection requiring IV antibiotics were excluded. Significant elevation of procalcitonin was considered present when levels exceeded 0.20 ng/mL. In-hospital and post-discharge outcomes were compared between groups of patients with and without elevated procalcitonin levels.

Procalcitonin ≥ 0.20 ng/mL was seen in 6.0% of patients (N=104). This group of patients had lower serum albumin, lower hemoglobin, higher leukocyte count, higher C-reactive protein, higher blood urea nitrogen, higher heart rate and more pulmonary rales. Interestingly, no significant differences were observed between the two groups in terms of severity of heart failure evidenced by left ventricular ejection fraction (LVEF) or B-type natriuretic peptide (BNP) levels. Patients with significantly elevated procalcitonin levels were more often classified as treatment failure or unchanged status, and had an increased risk of 30-day all-cause mortality even after adjustment for established prognosticators; HR=2.3 (95% CI, 1.3-4.2), (P=0.005).

Patients with acute heart failure and significantly elevated procalcitonin levels, indicating probable undiagnosed/untreated bacterial infection, had poorer in-hospital and post-discharge outcomes, despite similar severity of heart failure.