Validation of a Novel, Rapid Sepsis Diagnostic for Emergency Department Use.

OBJECTIVES: To assess the in vitro IntelliSep test, a microfluidic assay that quantifies the state of immune activation by evaluating the biophysical properties of leukocytes, as a rapid diagnostic for sepsis. DESIGN: Prospective cohort study. SETTING: Five emergency departments (EDs) in Louisiana, Missouri, North Carolina, and Washington. PATIENTS: Adult patients presenting to the ED with signs (two of four Systemic Inflammatory Response Syndrome criteria, where one must be temperature or WBC count) or suspicion (provider-ordered culture) of infection. INTERVENTIONS: All patients underwent testing with the IntelliSep using ethylene diamine tetraacetic acid-anticoagulated whole blood followed by retrospective adjudication for sepsis by sepsis-3 criteria by a blinded panel of physicians. MEASUREMENTS AND MAIN RESULTS: Of 599 patients enrolled, 572 patients were included in the final analysis. The result of the IntelliSep test is reported as the IntelliSep Index (ISI), ranging from 0.1 to 10.0, divided into three interpretation bands for the risk of sepsis: band 1 (low) to band 3 (high). The median turnaround time for ISI results was 7.2 minutes. The ISI resulted band 1 in 252 (44.1%), band 2 in 160 (28.0%), and band 3 in 160 (28.0%). Sepsis occurred in 26.6% (152 of 572 patients). Sepsis prevalence was 11.1% (95% CI, 7.5-15.7%) in band 1, 28.1% (95% CI, 21.3-35.8%) in band 2, and 49.4% (95% CI, 41.4-57.4%) in band 3. The Positive Percent Agreement of band 1 was 81.6% and the Negative Percent Agreement of band 3 was 80.7%, with an area under the receiver operating characteristic curve of 0.74. Compared with band 1, band 3 correlated with adverse clinical outcomes, including mortality, and resource utilization. CONCLUSIONS: Increasing ISI interpretation band is associated with increasing probability of sepsis in patients presenting to the ED with suspected infection.

Retrospective identification of infection in the emergency department: A significant challenge in sepsis clinical trials.

BACKGROUND: This study examined three methods for retrospectively identifying infection in emergency department (ED) patients: modified objective definitions of infection (MODI) from the CDC/NHSN, physician adjudication determination of infection, and ED treating physician behavior. METHODS: This study used a subset of data from a prospective sepsis trial. We used Fleiss's Kappa to compare agreement between two physicians retrospectively adjudicating infection based on the patient's medical record, modified infection definition from the CDC/NHSN, and ED treating physician behavior. RESULTS: Overall, there was similar agreement between physician adjudication of infection and MODI criteria (Kappa=0.59) compared to having two physicians independently identify infection through retrospective chart review (Kappa=0.58). ED treating physician behavior was a poorer proxy for infection when compared to the MODI criteria (0.41) and physician adjudication (Kappa = 0.50). CONCLUSIONS: Retrospective identification of infection poses a significant challenge in sepsis clinical trials. Using modified definitions of infection provides a standardized, less time consuming, and equally effective means of identifying infection compared to having multiple physicians adjudicate a patient's chart.

Assessment of a Cellular Host Response Test as a Sepsis Diagnostic for Those With Suspected Infection in the Emergency Department.

OBJECTIVES: Sepsis is a common cause of morbidity and mortality. A reliable, rapid, and early indicator can help improve efficiency of care and outcomes. To assess the IntelliSep test, a novel in vitro diagnostic that quantifies the state of immune activation by measuring the biophysical properties of leukocytes, as a rapid diagnostic for sepsis and a measure of severity of illness, as defined by Sequential Organ Failure Assessment and Acute Physiology and Chronic Health Evaluation-II scores and the need for hospitalization. DESIGN SETTING SUBJECTS: Adult patients presenting to two emergency departments in Baton Rouge, LA, with signs of infection (two of four systemic inflammatory response syndrome criteria, with at least one being aberration of temperature or WBC count) or suspicion of infection (a clinician order for culture of a body fluid), were prospectively enrolled. Sepsis status, per Sepsis-3 criteria, was determined through a 3-tiered retrospective and blinded adjudication process consisting of objective review, site-level clinician review, and final determination by independent physician adjudicators. MEASUREMENTS AND MAIN RESULTS: Of 266 patients in the final analysis, those with sepsis had higher IntelliSep Index (median = 6.9; interquartile range, 6.1-7.6) than those adjudicated as not septic (median = 4.7; interquartile range, 3.7-5.9; p < 0.001), with an area under the receiver operating characteristic curve of 0.89 and 0.83 when compared with unanimous and forced adjudication standards, respectively. Patients with higher IntelliSep Index had higher Sequential Organ Failure Assessment (3 [interquartile range, 1-5] vs 1 [interquartile range, 0-2]; p < 0.001) and Acute Physiology and Chronic Health Evaluation-II (7 [interquartile range, 3.5-11.5] vs 5 [interquartile range, 2-9]; p < 0.05) and were more likely to be admitted to the hospital (83.6% vs 48.3%; p < 0.001) compared with those with lower IntelliSep Index. CONCLUSIONS: In patients presenting to the emergency department with signs or suspicion of infection, the IntelliSep Index is a promising tool for the rapid diagnosis and risk stratification for sepsis.