Every minute counts when it comes to diagnosing and treating sepsis, an infection in the bloodstream that can turn deadly, fast.
Christiana Care Pathology and Laboratory Services has strengthened its arsenal in the fight against sepsis with a new protocol alert and some exciting new technology.
Sepsis is the body’s extreme response to a bacterial, fungal, viral or yeast infection. The release of chemicals into the bloodstream to fight the infection causes widespread inflammation that, if left untreated, can slow blood flow and damage organs. In the later stages, sepsis can progress to life-threatening severe sepsis or septic shock.
Severe sepsis claims the lives of more than 250,000 people a year in the United States. For every hour that appropriate treatment is delayed, sepsis-associated mortality increases by 7.5 percent. Early and accurate identification of sepsis is critical to survival.
“Our laboratory scientists are working closely with Christiana Care doctors and nurses to reduce mortality from sepsis and improve outcomes,” said Cheryl Katz, MS, MLS(ASCP)SH, vice president, Pathology and Laboratory Services. “This collaboration has spurred innovation in many areas, including our nationally recognized, award-winning Sepsis Alert protocol, but we continue to challenge ourselves to performance excellence when it comes to fighting this costly and potentially life-threatening condition.”
Tracking sepsis in the lab
There is a long list of tests that the lab uses to indicate sepsis, including blood cell counts, coagulation studies, lactic acid screening, liver enzymes, and C-reactive protein and procalcitonin (PCT) levels. A new protocol and new technologies enhance these capabilities.
Bands are immature white blood cells, which appear to increase at the onset of a blood infection. A Band Alert to the Emergency Department signals a high band count (> 20%) in a patient’s blood culture, which could be a potential early marker for sepsis.
“There have been some highly publicized cases reported in the literature where patients with unremarked elevated band counts have died from sepsis,” explained General Lab Manager Sherry Mertz, MT(ASCP). “Our laboratory worked with physicians in the Emergency Department and the Hematology Lab to devise a meaningful set of criteria for reporting when a patient’s band count is elevated, based on current guidelines and best practice recommendations.“
The guidelines are supported by work done by Marci Drees, M.D., MS, FACP, DTMH, infection prevention officer and hospital epidemiologist at Christiana Care and a Value Institute scholar, and her colleagues, published in The American Journal of Medicine in November 2012.
New lab tests are aiding the fight against sepsis at Christiana Care.
This testing allows us to more quickly identify what is causing the infection, whether it will respond to antibiotic therapy and which antibiotics would be most effective.
Procalcitonin (PCT) testing shortens the time to about an hour for results that formerly took three or four days. PCT levels become elevated in the blood when a bacterial infection is present. This can be an early indicator of sepsis. PCT testing can also differentiate from a non-infection inflammatory response, which would not respond to antibiotic therapy.
In the ICU, PCT levels are monitored regularly to guide timely de-escalation of antibiotic therapy. “This means the patient is on antibiotics only as long as necessary, which reduces their risk for dangerous antibiotic-resistant infections and allows them to go home sooner, which helps lower costs associated with a longer hospital stay,” Mertz said.
Verigene testing can detect and identify clinically significant, harmful bacteria in positive blood cultures in a fraction of the time it takes traditional methods — up to 48 hours faster. Verigene can also identify some of the resistant markers to commonly prescribed antibiotics.
“This testing allows us to more quickly identify what is causing the infection, whether it will respond to antibiotic therapy and which antibiotics would be most effective,” explained Microbiology Lab Manager Sarojini Misra, MS, SM(ASCP), SM(AAM). “With this information the doctor can target the treatment to the specific infection in the individual patient.”
Beating the clock against sepsis
“Sepsis is a time-sensitive disease that moves along a spectrum of evolving symptoms,” said Ryan Arnold, M.D., director of Emergency Medicine Research and clinical investigator at the Value Institute. “A patient’s condition could start out as a very mild disease but then progress to a life-threatening one very quickly without timely and appropriate treatment.”
Dr. Arnold says the ability to identify sepsis early and accurately combined with prompt treatment with IV fluids and targeted antibiotics is critical to saving lives.
“When you are dealing with sepsis it is not a slam dunk,” he said. “There is a whole field of diagnostics in development looking for more definitive methods to confirm the presence of infection and guide decisions on how many and what antibiotics to prescribe. With these technologies we are moving closer and closer to more personalized medicine, where we are not using algorithms but rather patient specific data to determine the correct treatment.”
Dr. Arnold is collaborating with Katz and her team on an observational study of heparin-binding protein (HBP) as a potential new biomarker in the blood to identify patients at risk for developing severe sepsis or septic shock. Christiana Care is currently the only U.S. institution collecting data for this study.
The results of Dr. Arnold’s previous work with investigators in Sweden recently were accepted for publication in Critical Care Medicine. He continues this work with colleagues at Christiana Care, collecting data on HBP levels in sepsis patients admitted from the Emergency Department at Christiana Hospital.
“Our focus is on patients whose clinical condition is challenged, but who have not progressed to severe infection to determine if HPB is an accurate predictor of those at risk for deterioration,” Dr. Arnold explained.
“Without the collaboration of our team members in the lab who donated their time to run the tests for us, we never could have progressed this far in our study,” he said. Research collaborations like these, he says, are needed to uncover more and more clues to cracking the code for sepsis.