Influenza Point-of-Care Tests Influence Patient Outcomes

Point-of-care testing for influenza in ambulatory care settings was shown to influence physicians’ prescribing and testing decisions, particularly for children in emergency departments, according to research published in Clinical Infectious Diseases.

A systematic review of influenza point-of-care testing vs normal ambulatory settings was conducted to determine their effect on patient outcomes. Of 12,928 citations screened, 7 randomized studies and 6 nonrandomized studies were included, with most of the evidence coming from pediatric emergency departments.

In the randomized studies, the risk for bias was moderate, and point-of-care testing had no effect on admissions (estimated risk ratio [RR], 0.93; 95% CI, 0.61-1.42; I²=34%), returning for care (RR, 1.00; 95% CI, 0.77-1.29; I²=7%), or antibiotic prescribing (RR, 0.97; 95% CI, 0.82-1.15; I²=70%), but did increase the prescribing of antivirals (RR, 2.65; 95% CI, 1.95-3.60; I²=0%). Point-of-care testing reduced orders for complete blood counts (RR, 0.80; 95% CI, 0.69-0.92; I²=0%), blood cultures (RR, 0.82; 95% CI, 0.68-0.99; I²=0%), and chest radiography (RR, 0.81; 95% CI, 0.68-0.96; I²=32%), but not urinalysis (RR, 0.91; 95% CI, 0.78-1.07; I²=20%). The time in emergency department did not change. The risk for bias was higher in the nonrandomized studies, and fewer studies reported these outcomes; in some, the findings were reversed or attenuated, such as fewer antibiotic prescriptions and less urinalysis in tested patients.

According to study investigators, this review employed a comprehensive search strategy and likely did not miss any large bodies of work that would change the interpretations of the results. However, there was little evidence from primary care, and most of the evidence came from low-sensitivity rapid antigen detecting tests. The study authors also noted that better tests would increase physicians’ confidence to act on the results and provide fewer false negatives.

Overall, the investigators concluded that “[point-of-care tests] for influenza have a role in children with influenza-like illnesses, particularly in emergency departments and during influenza epidemics,” but they also cautioned that “[t]ests are not a substitute for clinical assessment.”

The researchers also advised that further studies of point-of-care testing in both adults and children are needed, and that there is a knowledge gap concerning primary care settings. Future work should also include clinical course and mortality and morbidity measures, and also explore appropriate contexts for point-of-care testing use and implementation.

Reference

Lee JJ, Verbakel JY, Goyder CR, et al. The clinical utility of point-of-care tests for influenza in ambulatory care: A systematic review and meta-analysis [published online October 4, 2018]. Clin Infect Dis. doi: 10.1093/cid/ciy837