Put It on the Board, 11/14

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For Ebola cases, weighing broader, faster diagnostics

November 2014—Amid initial confusion over Ebola-related safety protocols for health professionals providing direct patient care, laboratory professionals report hearing a consistent message from the CDC on proper specimen handling. The pressing question for laboratories is how best to approach testing with potential Ebola patients given the dual imperatives of preventing exposure and offering faster diagnostic answers.

Pathologists tell CAP TODAY that a smart strategy on Ebola has to involve getting clinicians, lab professionals, and administrators on the same page. That multidisciplinary approach to the disease was taken at University of Chicago Medicine, which in October saw one case of suspected Ebola at its medical center. The patient tested negative.

Dr. Beavis

Kathleen G. Beavis, MD, is interim director of the academic medical center’s laboratories and medical director of the microbiology and immunology laboratories. In early discussions with other U. of C. stakeholders, Dr. Beavis pushed hard to make a wider menu of tests available to patients suspected of Ebola while they awaited definitive results from the Centers for Disease Control and Prevention.

Dr. Beavis says she was “not satisfied” with a protocol that would mean waiting the 12 to 48 hours it could take to get a conclusive Ebola result before offering “broader diagnostics.” By September, she and her colleagues were able to persuade administrators and others to pursue a different strategy. When a patient who meets criteria for potential Ebola virus disease arrives, a special room near the isolation area is set up with instrumentation including BioFire’s FilmArray to run the company’s rapid respiratory, gastrointestinal, and blood culture identification panels. Thin-smear malaria testing also will be done when appropriate.

A similar approach was taken at Emory University Hospital, which by early November had successfully treated four Ebola patients. The hospital created “a self-contained POC laboratory” within its quarantine facility, which involved use of the FilmArray to “detect a panel of viral, bacterial, fungal, or parasitic pathogens” (Hill CE, et al. Lab Med. 2014; 45: e109–e111).

Dr. Beavis hopes this kind of protocol will yield better care for patients.

“It is much likelier the patient has one of the bacterial causes of diarrhea, for example, than Ebola. Let’s get that diagnosed. . . . This is our challenge as pathologists, and as physicians—to offer the broadest range of diagnostic testing that we can,” says Dr. Beavis, a member of the CAP’s Microbiology Resource Committee.

Another member of that committee, Benjamin Pinsky, MD, PhD, directs the clinical virology laboratory at Stanford Healthcare and Stanford Children’s Health. He says the notion of offering additional testing options for potential Ebola patients is “something we’ve been thinking about.”

“We will be offering malaria testing by rapid antigen, as well as thin smears,” he says. “That will be available. But at this point, we are not planning to perform respiratory virus testing with the anticipation that if the physicians believe the patient is sick enough, then they will just empirically treat them with Tamiflu.”

The CDC does not advise the exclusive use of POC testing while awaiting Ebola test results, says Nancy E. Cornish, MD, a medical officer in the agency’s Division of Laboratory Science and Standards.

Dr. Cornish

“There are a lot of things that need to be taken into consideration before deciding how you’re going to handle these specimens,” she tells CAP TODAY. “Laboratorians are well equipped to sit down and look at their laboratory, look at their instrumentation, and determine how they are going to handle this kind of testing.”

Dr. Cornish says the CDC’s lab-specific guidance on Ebola has remained consistent, unlike the shift seen in the agency’s recommendations on personal protective equipment to be donned by health professionals in direct contact with patients. In October, the CAP published an Ebola update on its website that consolidates the agency’s advice on handling specimens that have or may have Ebola. The document, along with several pertinent links to other CDC guidance, is at http://j.mp/capebola.

Suspected Ebola specimens must be sent to the CDC or one of about 30 labs that are part of the agency’s Laboratory Response Network for testing with the Department of Defense’s EZ1 real-time RT-PCR assay. A negative result with that test rules out Ebola, but a positive requires confirmation at the CDC using two additional RT-PCR assays: the CDC Ebola virus NP real-time RT-PCR and the CDC Ebola virus VP40 real-time RT-PCR. While the instrument time for that first rule-out test is between four and six hours, Dr. Cornish says, actual TAT varies depending on where the testing is done and how long it takes to transport the specimen there. Dr. Cornish advised laboratory professionals to consult with their state’s public health laboratory to determine how quickly results can be available.

In late October, hospital labs got an option for faster results when the Food and Drug Administration gave emergency use authorization to a commercial Ebola test with an instrument time of about one hour. The Biothreat-E assay also runs on the FilmArray platform and was already being used at Emory. The emergency authorization makes it available to moderate- and high-complexity CLIA labs, and the test is priced at $185 per kit. The FilmArray instrument, already in place at more than 300 American hospitals, costs $39,500.

That one-hour turnaround time can make an impact that goes beyond clinical care, says Matt Scullion, vice president of sales and marketing at BioFire Defense, a division of BioMérieux.

“If you have to wait 12 to 48 hours to get answers back from the CDC lab, rather than have the results ready in one hour, that’s time, stress, and patient care being held up because you don’t have the diagnostics,” Scullion says. “From a public, psychological perspective, knowing the answer in an hour… makes a huge difference.”