Rapid tests might decrease the rate of antibiotic prescriptions, solidifying their role in stewardship programs. But they seem to have little or no impact on the dispensing of these medications to treat sore throat, according to the authors of a study in the Cochrane Database of Systematic Review.
Rapid tests for group A streptococcus evolved during the 1980s as point-of-care devices designed to help physicians manage patients with sore throat. While dozens of diagnostic accuracy studies have taken place, few have examined patient-relevant outcomes, said Jérémie F. Cohen, MD, PhD, senior researcher at Necker Hospital for Sick Children, an associate professor at the Université de Paris, France, and the study’s corresponding author.
He and his colleagues set out to evaluate the impact of rapid tests on antibiotic use, based on evidence from randomized trials. “We hypothesized that rapid tests could help to reduce antibiotic prescription rates, which is critical in the context of the fight against antimicrobial resistance,” said Cohen. The authors defined antibiotic prescriptions as medicines prescribed by healthcare providers, whereas antibiotic dispensing included medicines accessible in pharmacies.
Combing through clinical trial registries and databases, Cohen and his colleagues identified five randomized controlled trials covering 2,545 participants with sore throat in primary care settings. Two trials originated from the United Kingdom, three others came from Canada, Greece, and Spain. The studies either combined rapid tests in conjunction with a clinical scoring system, gave physicians an option of using the tests in combination with a scoring system, or in one case, just used the tests.
Rapid tests were associated with a 25% absolute decrease in antibiotic prescription rates. However, there was no significant impact on antibiotic dispensing. This could in part be due to less available data on dispensing. While all five studies addressed antibiotic prescriptions, only the two U.K. studies addressed antibiotic dispensing.
Cohen cited two reasons for the absence of effect on antibiotic dispensing:
- The U.K.’s frequent practice of “delayed antibiotic prescriptions” in which prescriptions are written in advance and should be filled only if a patient’s condition persists or worsens.
- Missing data (about 25%) on the dispensing outcome.
“Evidence regarding antibiotic dispensing was limited to the two U.K. trials that were in fact conducted as part of the same overarching study (the PRISM study),” explained Cohen.
For clinical labs, Cohen suggested, the biggest takeaway is rapid tests have the potential to substantially reduce antibiotic prescribing in patients with a sore throat. “Because of their low cost and low technical complexity, we believe they could play a critical role in antibiotic stewardship programs, including those in low-resource settings,” he said.
Little or no difference may exist between patients managed on clinical grounds alone and those managed with rapid testing. However, the evidence remains unclear. “More studies are needed to assess the efficacy and safety of rapid test‐guided antibiotic prescribing, notably to evaluate patient‐centered outcomes and variability across subgroups,” the authors suggested.
More specifically, future trials should explore differences in impact across age groups (children versus adults) and settings (office-based versus hospital-based physicians), Cohen said. “We also encourage future trials to investigate not only the effect of rapid tests on antibiotic use but also other patient-relevant outcomes such as the duration of symptoms of sore throat and fever, quality of life measures, and patient satisfaction,” he said. In addition, researchers should compare rapid tests for group A strep to point-of-care tests for other biomarkers that might be used to assess patients with sore throat, such as C-reactive protein.
A new generation of molecular point-of-care tests for detecting group A strep is now on the market. “Beyond their accuracy, their impact should be evaluated,” Cohen suggested.