Real-World Experience With Procalcitonin Use for Lower Respiratory Tract Infections

Abstract

Background. Evidence from several randomized controlled trials has shown that procalcitonin (PCT) can be used to safely decrease antibiotic use and guide appropriate duration of antibiotic therapy for lower respiratory tract infections (LRTIs). However, many of these trials were not conducted in the United States, and there is a little data regarding real-world use of PCT. Methods. In 2011, our 650-bed academic medical center implemented PCT testing with education and algorithms for interpretation. A retrospective cohort study was conducted assessing PCT algorithm compliance and outcomes for patients with compliant versus noncompliant therapy from July 2013 to June 2014. Inpatients ≥19 years old with a diagnosis of LRTI based on ICD-9 codes and clinical criteria and ≥1 PCT level were included. Patients were excluded if assigned to a surgical service, received a cytokine stimulating agent, or had a past medical history of cystic fibrosis, small cell lung cancer, or thyroid cancer. Compliance with the initial PCT algorithm was assessed for all patients. Outcomes, including antibiotic utilization, hospital length of stay, in-hospital mortality, 30-day readmission, and antibiotic adverse events were compared for compliant versus noncompliant therapy. Results. A total of 153 patients were included. Mean age was 64 years, 51% were male, and 84% were on a medicine team. The most common diagnosis was chronic obstructive pulmonary disease exacerbation (50%) and pneumonia (43%). Most patients (74%) only had 1 PCT level ordered. Initial algorithm compliance was 44% with noncompliance primarily due to initiation or continuation of antibiotics with a low PCT. For patients with a low initial PCT, algorithm compliance was associated with shorter duration of therapy (1.3 versus 5.9 days, p = 0.0001) and fewer number of antibiotics prescribed (1 versus 2, p = 0.0001). There were no significant differences in clinical outcomes or antibiotic adverse events between groups. Conclusion. In patients with an initially low PCT, algorithm compliance was associated with a significant decrease in antibiotic use without compromising clinical outcomes.