Contributed Commentary by David Ludvigson
May 16, 2018 | Sepsis is not particularly well known among the public, but its toll is staggering: one in three people who dies in a hospital in the United States has sepsis, according to the U.S. Centers for Disease Control and Prevention. In this country alone, 1.5 million people get sepsis each year and 250,000 of them die from it.
In the diagnostic community, sepsis is an enemy we know all too well. It has a number of causes — often triggered by lung, kidney, or urinary tract infections — and its symptoms are non-specific, making it very difficult to diagnose. To make matters worse, every hour of delayed treatment increases mortality by 8%. The pressure to diagnose sepsis quickly and accurately is intense.
While great effort is going into developing sepsis diagnostics that do a better job of identifying the pathogen responsible, little attention has been paid to another area that stands to have a significant impact on sepsis care: triage. Just as there is a need to determine what’s causing a patient’s sepsis, there is an equally pressing and distinct need to figure out whether or not a patient has sepsis. This simple verdict is enough to get treatment started, regardless of the underlying cause, and can dramatically improve a patient’s chances of surviving sepsis.
Triage diagnostics that would rapidly identify patients with sepsis would be an important new tool in the fight against this health threat — even more so if they could be performed at the point of care.
Today’s Tests
Sepsis occurs when an overwhelming inflammatory response is triggered, typically by an infection. If the overreaction cannot be de-escalated, the condition is likely to be fatal. Early indicators of sepsis are as non-specific as they come: high heart and respiratory rates, with a fever or abnormally low temperature. As the condition worsens, patients typically have reduced urine output, abdominal pain, and difficulty breathing. The final stage, septic shock, is marked by extremely low blood pressure that is not improved with the administration of fluids. These symptoms make it difficult to distinguish sepsis from a host of other medical conditions, including other complications of infections.
Current sepsis tests often focus on lactate levels, which can be informative but are non-specific indicators of sepsis. Rapid point-of-care testing for biological markers other than lactate is not available. The best tests for sepsis right now are blood cultures performed in clinical labs. However, the turnaround time for these tests can be at least a day; newer molecular tests, while faster, still require several hours. Such delays put too many patients’ lives at risk by allowing cases to progress from the early, more treatable stages to the advanced, often irreversible stages of sepsis.
Triage Testing
Patients and the healthcare community alike would benefit from a shift to thinking of sepsis testing as a two-stage process: first, a simple and rapid test with additional information about the patient’s condition and the possible onset of sepsis; and second, a test or set of tests focused on identifying the underlying root cause of the patient’s condition.
When sepsis treatment — typically antibiotics and fluids — is administered early, patient outcomes are significantly improved. An early triage test that signals the presence or absence of sepsis would be enough to begin this life-saving treatment. For best results, however, that information is needed in a very short critical care window, just 30 minutes from the first signs. The ideal triage test would have to generate results in 10 or 15 minutes in order to make a difference.
If such a test were portable, the approach to sepsis treatment could change radically. For instance, using this test where the patient is — whether that’s in a nursing home, a remote location, or a hospital — would allow first responders and emergency teams to begin treatment, rather than waiting until the patient gets to a healthcare facility and is diagnosed by a clinical laboratory. Patients could begin treatment hours or even days earlier, when damage is least severe and the condition has the best chance of being reversed.
Today, this kind of rapid, portable triage test for sepsis is in development. Currently in clinical trials, the test measures three sepsis-related biomarkers (lactate, procalcitonin, and C-reactive protein) for better specificity and sensitivity than current point-of-care lactate tests offer.
What’s Next
Triage testing promises to do for sepsis patients what fast administration of clot-busting drugs has done for stroke patients: halt progression of the condition with early intervention to save lives. It would empower first responder teams to start treatment while saving the more laborious, time-intensive strain identification sepsis testing for clinical labs to hone treatment selection. At long last, we may finally have an opportunity to better address one of the costliest threats to patient health.
David Ludvigson is President and CEO of Nanomix, a company implementing mobile, rapid diagnostic testing for critical disease states using a proprietary handheld platform. He can be reached at DLudvigson@nano.com.