Excluding infection through procalcitonin testing improves outcomes of congestive heart failure patients presenting with acute respiratory symptoms: results from the randomized ProHOSP trial

Background/objectives: We sought to determine whether exclusion of infection and antibiotic stewardship with the infection biomarker procalcitonin improves outcomes in congestive heart failure (CHF) patients presenting to emergency departments with respiratory symptoms and suspicion of respiratory infection.

Methods: We performed a secondary analysis of patients with a past medical history of CHF formerly included in a Swiss multicenter randomized-controlled trial. The trial compared antibiotic stewardship according to a procalcitonin algorithm or state-of-the-art guidelines (controls). The primary endpoint was a 30-day adverse outcome (death, intensive care unit admission); the secondary endpoints included a 30-day antibiotic exposure.

Results: In the 110/233 analyzed patients (47.2%) with low initial procalcitonin (<0.25 μg/L), suggesting the absence of systemic bacterial infection, those randomized to procalcitonin guidance (n=50) had a significantly lower adverse outcome rate compared to controls (n=60): 4% vs. 20% (absolute difference -16.0%, 95% confidence interval (CI) -28.4% to -3.6%, P=0.01), and significantly reduced antibiotic exposure [days] (mean 3.7 ± 4.0 vs. 6.5 ± 4.4, difference -2.8 [95% CI, -4.4 to -1.2], P<0.01). When initial procalcitonin was ≥0.25 μg/L, procalcitonin-guided patients had significantly reduced antibiotic exposure due to early stop of therapy without any difference in adverse outcomes (25.8% vs. 24.6%, difference [95% CI] 1.2% [-14.5% to 16.9%, P=0.88]).

Conclusions: CHF patients presenting to the emergency department with respiratory symptoms and suspicion for respiratory infection had decreased antibiotic exposure and improved outcomes when procalcitonin measurement was used to exclude bacterial infection and guide antibiotic treatment. These data provide further evidence for the potential harmful effects of antibiotic / fluid treatment when used instead of diuretics and heart failure medication in clinically symptomatic CHF patients without underlying infection.