After a patient with a high risk of sepsis spikes a fever or develops other symptoms, a delay in hours, let alone days, to place the patient on the right drug can dramatically increase mortality rates.
The mortality rate for sepsis rises by 8% every hour it goes untreated. And the overall toll of sepsis on human life and health care costs is staggering – a 30% mortality rate and a cost upwards of $27 billion per year, the most expensive hospital inpatient cost in the United States. While improved vigilance and preventive medical practices are critical in the fight against sepsis, a glaring area of need is diagnostics. Diagnostics are the bottleneck to timely and appropriate therapy. If doctors had better information faster, more patients with sepsis would be saved – and the massive cost burden on our health system would be reduced.
To understand how the current standard of care for sepsis diagnostics can be improved – it is important to understand the current workflow. I have conducted a number of studies in this space and one of my clients has allowed me to share the specifics of their findings, which are consistent with other studies I’ve performed. This study was a retrospective analysis of historical blood culture laboratory information system (LIS) data from 7 U.S. hospital laboratories and one hospital network laboratory. These labs perform testing for a total of 10 hospitals and 4 outpatient clinics. In addition, each respondent was interviewed to confirm the process flow in the lab and the specific methods used. A total of 428 patient samples were analyzed from the time of sample collection to final identification (ID) of the pathogen and antimicrobial susceptibility testing (AST). Workflow reported in the LIS for all samples included sample collection time, central receipt, blood culture initiation, Gram stain (GS) result, final ID, and AST.
The results focused on the time elapsed before clinicians had information that could impact care of a potential sepsis patient, not isolated performance of a given test. And the results were a sobering reminder of the hours and often days lost before clinicians have the complete set of information they need to determine the best course of treatment. The average time to final species identification was more than 2.5 days. Advances in post-blood culture diagnostics are clear in this analysis – in the 22% of cases where rapid molecular tests produced an “initial” ID, the average time to initial ID result was more than 1.5 days – but when every hour counts in sepsis management, these results still have significant limitations.
The primary culprit of these multi-day delays is clear: blood culture. Of the hundreds of positive samples, the average time from sample collection to blood culture positivity was 29 hours.
Even with the easiest and fastest pathogens to be diagnosed by blood culture, there were no circumstances, regardless of hospital type or technology used, where the average time for detection occurred in less than 12 hours.
The conclusion from this real laboratory analysis is that to provide the best care for septic patients, diagnostics must advance beyond blood culture-based methods. The current delay in pathogen identification results leaves clinicians with two very bad options – miss patients with potentially deadly infections or significantly over-treat a patient population and drive drug resistance and the growth of superbugs. Both are bad for patients and both cost the healthcare system billions of dollars.
For our hospitals to provide the best care and reduce the most unnecessary costs, the next generation of sepsis management requires rapid diagnostics that are independent of blood culture. These tests, which eliminate lengthy blood culture delays and time-consuming handoffs, have the potential to provide identification results within 3 hours, up to 10 times faster than the current standard.
One of the leaders in this emerging market is T2 Biosystems, which has an FDA-cleared test for the detection of Candida bloodstream infections that provides direct from whole blood results in 3-to-5 hours, as well as a bacteria panel submitted to the FDA. The initial results from hospitals’ clinical use are demonstrating the expected clinical value of avoiding blood culture; for example, Henry Ford Health System reported that patients were put on appropriate therapy over half a day faster with the use of T2Candida and experienced a 7 day length of stay reduction in the ICU.
And many others are moving into this space. Roche Diagnostic’s CE Marked Septifast detects bacteria and fungi directly from whole blood and newcomers like London-based DNAe are leveraging novel technologies to detect sepsis-causing pathogens.
As with any leap forward in care, challenges remain for hospitals to adopt direct-from-blood diagnostics. These tests require an additional cost to the lab, but the benefit – in cost and improved patient outcomes -- is to the entire hospital. In addition, these important advances can present a burden to the workflow of labs currently performing a high volume of blood cultures. Therefore, adoption will require support not only from the lab, but also from other stakeholders, including hospital leadership.
The cost savings from improved patient care - reduced length of stay, fewer antimicrobials, and even reduced mortality - must be factored in to the economic analysis. If a hospital takes a siloed view of the laboratory budget versus overall cost impact to that hospital, technology adoptions will be stunted to the detriment of patients, and ironically, the hospitals’ bottom line. However, if there is a widespread adoption of new diagnostics by hospital laboratories it will mark a new era in sepsis management, one that should bring much needed improvements in patient care and reductions in mortality.
By Larry Worden
As a professional with 40 years of experience in the field of medial/scientific marketing research and consulting, my primary focus in on vitro diagnostics. Although no longer involved in the day-to-day management of Market Diagnostics International (MDxL), the company I co-founded in 2006, I maintain an ownership interest and have exclusive access to MDxL’s industry databases to serve the needs of my IVD Logix clients.