The Impact of Point-of-Care Polymerase Chain Reaction Testing on Prescribing Practices in Primary Care for Management of Strep A: A Retrospective Before-After Study

Implementation of point-of-care polymerase chain reaction tests was associated with a 44.1% reduction in inappropriate antibiotic prescribing in those with a group A beta-hemolytic Streptococcus-negative result. Laboratory-based diagnostic test results had minimal impact on overall antibiotic prescribing practices in primary care. Background Rapid antigen detection tests (RADTs) are the standard of care (SOC) for testing in patients with suspected group A i(2)-hemolytic Streptococcus (Strep A) infection. Due to lower sensitivity, guidelines recommend confirmatory microbiological culture following negative RADT results. This process is time-consuming, and adherence is often poor, resulting in high rates of inappropriate antibiotic prescribing. We sought to evaluate the impact of switching from RADTs to point-of-care (POC) polymerase chain reaction (PCR) testing on use of antibiotics in primary care, when used as part of an antibiotic stewardship initiative. Methods In this retrospective before-after study, electronic medical records of any patients presenting with suspected acute pharyngitis (June 2018-May 2019) across 15 outpatient primary care clinics were evaluated. Strep A was detected using the cobas Strep A assay (cobas Liat system). Results Analysis of 10 081 eligible patient records showed that POC PCR testing resulted in a 44.1% reduction in antibiotic prescribing for patients with a negative POC PCR test result (10.1% PCR vs 18.0% RADT; P < .0001). Rates of antibiotic prescription varied across clinical sites, ranging between 10.7% and 33.8% and 12.4% and 34.4% during the use of PCR tests and RADTs, respectively. POC PCR had no impact on prescription rates in patients with positive POC test results compared to RADTs (76.2% vs 76.5%, respectively). More than 99% of antibiotics were prescribed during the initial primary care encounter. Conclusions As part of a broader antibiotic stewardship initiative, implementation of POC PCR as SOC in outpatients with acute pharyngitis symptoms reduced the volume of inappropriate antibiotic prescriptions.