In The News: PCR Tests Don’t Predict Response to Antibiotics in Coughing Kids

A recent story by Medscape looked at a research study on the recent practice of using polymerase chain reaction (PCR) testing to identify patients with acute cough who have bacterial infections amenable to antibiotic treatment. The findings show that, even when throat swabs reveal bacteria in children with respiratory infections, antibiotics make little difference in rate of recovery.

Study authors found the PCR tests could detect bacteria but could not identify which infections warranted antibiotic treatment. Whether given amoxicillin or placebo, testing did not determine how soon children got better or the pathogen present. The results point to clinicians refraining from using PCR tests until benefits from usage are more evident.

The study used data from a placebo-controlled trial of more than 400 children aged 6 months to 12 years who had acute lower respiratory tract infections (LRTIs) in the United Kingdom. Specifically, it included children who had had a cough for less than 21 days, as well as other lower respiratory tract symptoms, such as shortness of breath, sputum, or pain. Children with coughs that were deemed to be noninfectious in origin or that were almost certainly linked to a virus were excluded.

The authors reported no clear demonstrated effect of antibiotics on duration or severity of symptoms, according to microbiological subgroups. Without such clear evidence between microbiological findings in the upper tract and the impact of antibiotics, they went on to suggest a limited role for microbiological point of care tests for children with uncomplicated LRTI in primary care.

PIDS member Rebecca Same, quoted in the article, was not surprised by the findings, “We already know that these children don’t need antibiotics. So this test does not really help…one way or another and could be harmful because it could convince people to give antibiotics for something that is not fundamentally a bacterial infection.”