Rapid Testing For Asthma: A Reality?
My current position working with the Pacific Hepatitis C Network has provided me no shortage of interesting opportunities to learn (seriously, some ridiculously interesting). I “hosted” a conference call that was a training session for how to do the rapid screening test for hepatitis C. It is simple enough that non-healthcare providers, such as my friend and colleague Daryl, who is also a peer navigator, can do the screening on another person.
I intended to start the call recording and then wander off. Instead, I became so intrigued within the first 2 minutes that I wandered off in view of my laptop with my Bluetooth earphones in! It just so happened in my scan of the asthma news, a mere 20 minutes after I ended the meeting, that I saw an article called Rapid Test to Diagnose Asthma.
What is a rapid screening test for asthma?
Most often, rapid screening tests take a small sample of blood or swab of another area of the body (such as a step throat swab) to check for the presence of a virus or disease. These tests can take varying amounts of time to complete. However, they are much quicker (but often less sensitive) than tests done in a lab, such as when you have a blood sample or other specimen “taken away”.
Rapid tests can give preliminary results much more quickly than the usual several days later. For instance, the rapid hep C test I mentioned above provides results to be read after 20 minutes, whereas the rapid flu test takes about 15 minutes. For reference, lab work would usually take 1-3 days in both cases.1. Is it possible that rapid screening testing for asthma can become a reality in the future?
How does a rapid screening test work?
Each rapid screening test works differently. Because the screening test mentioned above for asthma was a blood test, I presume it can be roughly compared to the test I observed for hepatitis C antibodies.2 Recall, the asthma test doesn’t yet exist (at least not in its entirety), so it’s kind of all speculation from us on the outside how it could work.
Our guide to the rapid hep C test was Sofia, from the British Columbia Centre for Disease Control, and her colleague Amelia. It’s really hard for me to describe what the test looks like, so here’s how it was done.
Just like checking blood sugar, the side of the fingertip is pricked. Blood is squeezed out onto a “wand” of sorts and placed in a testing solution. After about 20 minutes, the indicator window shows if the test is positive. Seriously, it’s that simple. I presume most screening tests like this one are pretty close to that simple, too.
The future of diagnosing asthma?
That the rapid screening test for asthma would be done in a completely different way than those used for viruses: by monitoring immune cells under a specialized microscope for movement patterns. This is due to the consideration that the movements of immune cells in people with asthma are slower than that of people without.2 The article continues on to note artificial intelligence will play a key role in monitoring the movement patterns of the cells for 90 minutes.2
Of course, I have many questions about this: is this pattern of cell movement truly specific to asthma? Or is it specific to a specific asthma phenotype, or inflammatory or atopic disease as a whole? Bearing answers to that, would this rapid screening for asthma test be reliable in all or only some populations or subgroups?
Artificial intelligence-based tests aside, I still think we could be a ways off from diagnosing asthma by a rapid blood test like this. Unlike a virus (such as hep C, HIV, and the flu), biomarkers seem to be the gold standard of these rapid tests (not cell dancing or whatnot!). I don’t think we currently have a reliable biomarker. We have a bunch of possible contributors like IgE, eosinophils, genes—and so on—but not a single consistent, reliable indicator. The variables in each person’s asthma, from internal cause to presentation, is what can make asthma so challenging to diagnose.
However, it’s pretty cool to think about. Imagine if we could use a simple blood test—and better yet, a fast one—to help correctly diagnose or rule out asthma! It would sure make a lot of people’s lives easier—from healthcare providers to patients.
Have you ever gotten "moon face" as a side effect of prednisone?