Respiratory Testing

By Jim Poggi

The game keeps changing. Are you?

You may be asking yourself, “Why is Poggi offering a review of flu/respiratory tests in March? Most respiratory seasons peak by now.” While the timing is unusual, I have a couple of good reasons. First, your customer experience is fresh on their minds: Did the solution you provided work effectively? Were they satisfied with test results and workflow? Did they wish they had EMR connectivity? Were there unexpected back orders?

Second, the number of choices in respiratory testing has increased dramatically in the past few years and picking the right solution can be confusing. Asking the right questions of your customers in the coming months should solidify your recommendations during the summer when our suppliers offer special customer incentives to be ready for the peak season in the fall and winter. I intend to give you a few thoughts to mull over as you prepare to consult for your customers in the coming season. 

Range of choices
Less than 10 years ago, influenza and strep were the common waived respiratory testing choices in primary care. There were no molecular tests practical for our customers, no lateral flow test readers, no connectivity options and a narrow field of available tests, test methods and manufacturers.

Now the range of choices in methods, level of automation, connectivity and supplier options has dramatically increased. To put it into perspective, for flu tests alone there are currently 18 waived lateral flow flu kit choices with seven different reader options, including private label variations. On the molecular side of things, there are eight waived molecular tests on the market, with a total of 24 waived or moderate complexity molecular choices! Molecular instrumentation adds options for scalability and connectivity. But, even in the lateral flow flu test kit world, there are sophisticated reader options including connectivity and result reporting for flu incidence surveillance available to customers. The range of available respiratory tests has expanded to include RSV and pneumonia assays along with several other bacteria and viruses, notably human metapneumovirus, adenovirus and multiple species of parainfluenza and coronavirus.

So, how do you effectively evaluate the available choices and properly consult with your clients to provide the optimal solution for them? This article will summarize general test methodologies, with some focus on special features your customers may find valuable. In addition, it will offer additional considerations that will make a difference to certain customers. It will describe how PAMA (remember PAMA?) has leveled the Medicare reimbursement for molecular flu tests are raised the reimbursement level in the former lower reimbursement states. Finally, it includes my thoughts on “how and when do we know we have tested enough causes of respiratory illness”?

Product landscape

General Methodology	Waived?	Time to Result	Reader	LIS/EMR Connectivity	Special Features*
Rapid lateral flow	Yes; most	<15 min.	Some	A few	Anonymous result surveillance reporting
Rapid Molecular	Yes; about one third of available methods	15-30 min.	Yes; some are very sophisticated	Nearly all	Scalability; very wide range of available tests; anonymous result surveillance reporting
Immunofluorescence	No	1-4 hours	Yes	Yes	Direct and indirect methods are available

*Special features and overall respiratory test menu vary by manufacturer and model.  Be sure to consult with your respiratory kit manufacturer for ALL the pertinent details.

Additional customer considerations include overall test kit performance (sensitivity and specificity), scalability and desired respiratory test menu.

Overall kit performance
Rapid lateral flu kit performance has been improved by the requirements imposed by the CDC in 2017 regarding sensitivity and specificity for both flu A and B. As a result, if a good swab is collected (not always a great assumption), performance of lateral flow assays for flu is solid overall, and typically improves when a reader is used. For strep, molecular assays typically offer a “no need to confirm negative results” benefit that improves confidence in results as well as speeding up reporting of negative results. These benefits strongly support antibiotic stewardship. For RSV testing, since it is so important to avoid false negatives, the highest “negative predictive value” is an important consideration and molecular methods have the advantage here.

Scalability and work flow
From a work flow perspective, lateral flow has traditionally been faster since early readers had “one sample at a time” constraints. However, many readers offer batch testing capabilities that make them effective work flow solutions in practices where multiple samples need to be tested at the same time. In addition, most manufacturers now offer multiple respiratory method choices from lateral flow, lateral flow with readers and molecular options. So, it is possible to solve many individual customer needs with a single supplier’s solutions. Finally, some suppliers offer a choice of single test and multiple test analyzers which give the customer choices if they believe their testing volume will grow.

How PAMA helped
When the molecular flu Medicare CPT code was subject to individual carrier payment decisions, several carriers had rates below the average. With the current unified Medicare reimbursement under PAMA all states offer the same reimbursement for molecular influenza, CPT code 87502/QW.

Test to know
As the number of available respiratory tests continues to increase, your customers will need to decide which tests to offer to aid in diagnosis and effective patient treatment. The most common thought process tends to be for clinicians to require tests that allow them to quickly and effectively diagnose and treat the patient condition. Since many respiratory infections tend to be self-limiting in otherwise healthy patients, you can expect your customers to have varying opinions about the importance of offering some of the newer assays where treatment options are usually limited to supportive treatment.

So, do your homework now and learn from your customers’ input and experience during the past two seasons. Use this input as well as guidance from your respiratory testing suppliers to be fully prepared for the coming respiratory season. Respiratory testing is changing. Are you?