119 - Procalcitonin to Guide Antibiotic Therapy for Respiratory Infection: A Systematic Review of Systematic Reviews

Background: Antimicrobial resistance is an international calamity; closely linked to antibiotic use. Safely reducing antibiotic course length and overall use are imperative. Procalcitonin (PCT) is a biomarker expressed in serum in response to bacterial infection. Systematic reviews (SRs) evaluating PCT as an adjunct to guide antibiotic therapy have been performed but its use remains contentious. The aim of this SR of SRs was to evaluate the extent to which PCT impacts the likelihood of antibiotic initiation and antibiotic duration in cases of respiratory infection.

Methods: A systematic search of databases using an a priori strategy was conducted. SRs which reported an outcome related to antibiotic initiation and/or duration in the context of respiratory infection were included. Data extraction was performed by the first author and checked independently by a second author. The quality of SRs was assessed by two authors independently using ROBIS criteria. Disagreements were resolved by consensus with a third author. Results are presented narratively and in tabular format (Table 1 and Table 2).

Results: 13 SRs were included (see PRISMA diagram). The number of respiratory patients included in these SRs ranged from 308 to 6708 (median = 3457). There was a consistent finding of a statistically significant reduction in antibiotic initiation in the PCT study group compared to the control group (Table 1). SRs that meta-analysed antibiotic duration (n = 9) as a difference in days showed a median reduction of 2.15 days (reduction range 0.80 to 3.83 days) with PCT use.PRISMA Diagram
Table 1: Summary of odds ratios/ risk ratios in antibiotic initiation with the use of PCT
Table 2: Summary of difference in antimicrobial duration with use of PCT


Conclusion: PCT use leads to a reduction in antibiotic initiation for respiratory diseases. It also results in a decrease in antibiotic duration, but this finding was not consistently statistically significant. There are no data presented in the SRs about the impact of this on antimicrobial resistance.