After years of centralization in the clinical testing realm, the field is in the midst of a shift toward decentralization. This trend supports the goals of diagnostic stewardship and getting the right test to the right patient at the right time.
While point-of-care testing has been an option for some clinical situations for many years—rapid flu or rapid strep tests performed at primary care offices are good examples—the need for the full spectrum of testing options was starkly revealed during the COVID-19 pandemic. There was an obvious need for high-quality molecular tests that could be run in hospital laboratories and in reference laboratories. But with all of these clinical laboratories overwhelmed with testing demand, there was an equally clear need for point-of-care options, particularly at-home testing that made it possible for people to get a fairly accurate reading of whether they were contagious so they could take appropriate isolation measures to keep others safe.
For some healthcare situations, this is the model that will serve the entire clinical laboratory community best going forward: a hub-and-spoke approach that allows for all the benefits of centralized testing as well as the advantages made possible through decentralized testing.
While clinical lab testing is well established, it’s in point-of-care testing where innovation is needed most. Decentralized testing options must have accuracy approaching that of standard clinical lab tests, but they will also require the speed and ease of use that patients and healthcare professionals have come to expect from the era of rapid antigen tests.
Point-of-care testing in the past
To understand where point-of-care testing needs to evolve, it is worth looking at how it has been implemented in the past. Based on prior examples, it is understandable that many members of the clinical laboratory community may be skeptical that decentralized testing could ever produce truly reliable and useful results.
Perhaps the best-known examples of point-of-care testing involve the rapid antigen tests that have been used for influenza and group A streptococci. These lateral flow tests became popular among primary care physicians and urgent care clinics for their speed, often delivering results in 10 to 15 minutes. But within the clinical lab community, these tests became known for their lack of sensitivity, with a high rate of false negatives that sent many contagious patients home believing they didn’t need to worry about spreading infection. In several meta-analyses of these tests, sensitivity for rapid influenza A and B testing was 67.5% at best and 51% at worst.1 Sensitivity was lower for influenza B than influenza A, and lower for adults than children.
Due to sensitivity issues, many physicians regularly sent negative test samples to clinical laboratories for confirmatory molecular testing, as recommended by the U.S. Centers for Disease Control and Prevention.1 But even that was deemed inadvisable by the Infectious Diseases Society of America (IDSA), which in 2019 published new guidelines for flu testing in which they recommended against the use of rapid antigen tests.2 Instead, the IDSA now recommends the use of rapid molecular tests, which can generate results in an hour or less—still providing same-day answers for patients and physicians but with extremely high accuracy.
Respiratory testing should be first
While decentralized testing will be useful for a broad range of healthcare needs, it is likely that the first area where it will make a major impact is in respiratory infections. For a number of reasons, this will be the perfect test case to evaluate the utility of this model.
Respiratory testing capacity has always been unpredictable due to its seasonal nature. In summertime, testing ebbs for flu and respiratory syncytial virus (RSV). But in the winter, hospital labs can be overwhelmed by demand for these tests, leaving little bandwidth to manage all of the other clinical tests that have to be run. A reliable point-of-care test for the most common causes of respiratory infections would make it possible to offload much of the peak respiratory testing demand to pharmacies or urgent care clinics, freeing up the hospital laboratory staff to focus on testing for seriously ill patients. When flu, COVID-19, or RSV are at unusually high levels, hospitals might even set up tents or screening stations outside where patients could be given a point-of-care test, allowing those who are not sick enough to be admitted to get the answers they need while avoiding a testing burden on the central lab.
A decentralized model would also help in this space because respiratory infections are highly transmissible. If patients could get accurate results at home, at an urgent care facility, at a primary care office, or at a pharmacy, they could take appropriate measures to avoid infecting others. Each patient who stays safely at home could represent the end of a transmission chain, rather than the continuation of it. Point-of-care testing could reduce community spread and keep more people healthier.
Finally, respiratory testing has been primed for a decentralized approach thanks to advances from the COVID-19 pandemic. Substantial technology development for rapid molecular platforms—including molecular tests that could be performed by patients in their own homes—has paved the way for increased familiarity with point-of-care tests.
How decentralized testing fits
For optimal results, point-of-care platforms should be integrated into the testing strategy established by a clinical laboratory. Clinical lab teams know best where and how decentralized modes of testing could complement hospital and reference lab testing in their communities, with specific attention paid to the needs of their patient population. For labs serving a large elderly population, for example, perhaps setting up a point-of-care test platform in the local senior center or pharmacy would be most convenient and effective. Clinical labs have tracking data on which customers are submitting requests for testing, and this knowledge will be essential for ensuring that point-of-care testing is rolled out in the best way for the population they serve.
A combination approach could work for healthcare systems such as integrated delivery networks. Hospital labs would continue to run respiratory tests for admitted patients, while point-of-care tests could be used in urgent care and outpatient facilities to expand testing venues without increasing capacity in existing labs. In this case, using the same point-of-care platform in all of these sites would ensure consistency of results no matter where testing is performed.
In addition, point-of-care testing could be deployed for rural communities and remote facilities associated with integrated delivery networks to provide a better standard of care.
What’s next
It is clear that the testing market is shifting, and that decentralized testing options will be important for managing patient health going forward. With that said, though, point-of-care tests have much to accomplish before they can be broadly adopted. Technology development will be important to ensure accuracy on par with traditional molecular assays, ease of use so even lay people can operate the tests, minimal hands-on time to avoid creating a new testing burden outside the lab, and rapid results for optimal utility. Just as importantly, these developers will also have to collect data about how these platforms are used and what errors might arise to continually hone these new tests for mainstream use.
While that innovation happens—and it is happening, driven in large part by what the laboratory community learned from the COVID-19 pandemic—it will be important for clinical laboratories to begin thinking about how they could implement the best point-of-care options for respiratory testing in their own healthcare facilities. Any concerns about reducing revenues within the clinical lab can start to be addressed in the planning phase as leaders find ways to attribute point-of-care testing revenues to the clinical lab overseeing these platforms. Early adopters who figure out the best way to combine centralized and decentralized testing options for their patient populations will help establish efficient and effective models that can eventually be implemented in healthcare systems around the world.
References
1. Green DA, StGeorge K. Rapid Antigen Tests for Influenza: Rationale and Significance of the FDA Reclassification. J Clin Microbiol. 2018;25;56(10):e00711-18. doi:10.1128/JCM.00711-18.
2. Uyeki TM, Bernstein HH, Bradley JS, et al. Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 Update on Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management of Seasonal Influenza. Clin Infect Dis. 2019;5;68(6):e1-e47. doi:10.1093/cid/ciy866.
