Immunexpress Announces Publication Showing SeptiCyte RAPID® Identifies Septic Patients Most Likely to Have Positive Blood Cultures

Publication highlights strong association between a patient's sepsis risk and likelihood of positive cultures, with SeptiCyte RAPID results just 90 minutes after a blood draw

SEATTLE and BRISBANE, Australia, Feb. 12, 2026 /PRNewswire/ -- Immunexpress, a molecular diagnostics company focused on improving outcomes for patients with suspected sepsis, today announced the publication of a new multi-center study demonstrating that elevated SeptiCyte RAPID^® scores are strongly associated with blood culture positivity in sepsis patients.

The study, "Likelihood of Blood Culture Positivity Using SeptiCyte RAPID" is a post-hoc retrospective analysis of data from three prospective observational cohorts encompassing North America, Europe, and sub-Saharan Africa. The analysis included 506 critically ill and acute care patients, with sepsis independently adjudicated and blinded to SeptiCyte RAPID results.

Key Findings

• Higher SeptiScores^® were strongly associated with blood culture positivity, with >90% of blood culture–positive sepsis patients falling into the highest SeptiScore bands.
• No blood culture–positive sepsis cases were observed in the lowest SeptiScore band, highlighting the test' ability to identify patients at very low likelihood of sepsis.
• Diagnostic performance was strong, with an AUC of 0.91 for distinguishing blood culture–positive sepsis from non-infectious systemic inflammation (SIRS).

Importantly, binary cut-point analyses demonstrated 100% sensitivity at low SeptiScores (<5.0) and 100% specificity at high SeptiScores (>11.4) within this dataset, underscoring the potential clinical utility of SeptiCyte RAPID as an early risk-stratification tool.

Blood cultures remain a cornerstone of sepsis management, yet are frequently negative, delayed, or complicated by contamination. "The study findings suggest that SeptiCyte RAPID, when used alongside clinical assessment, may help clinicians prioritize which patients are most likely to benefit from blood cultures, interpret equivocal results, and potentially reduce unnecessary testing," stated Dr Maik von der Forst, Department of Anesthesiology, Heidelberg University Hospital Germany. "There is a need for tools that guide the use of microbiologic diagnostics in the hospital and especially in resource-constrained healthcare settings, emergency departments and ICUs."

For further information, to incorporate SeptiCyte RAPID into your hospital sepsis management program please contact [email protected].

About SeptiCyte^® RAPID

SeptiCyte^® RAPID is a sample-to-answer, cartridge-based, host response molecular test for sepsis using reverse transcription polymerase chain reaction (RT-PCR) to quantify the relative expression of two host response genes (PLAC8 and PLA2G7) from whole blood. SeptiCyte^® RAPID generates a SeptiScore^® within approximately one hour, reported across four interpretation bands reflecting increasing likelihood of sepsis. SeptiCyte^® RAPID is intended for use in conjunction with clinical assessments, vital signs, and other laboratory findings as an aid in differentiating infection-positive sepsis from non-infectious systemic inflammation.

SeptiCyte^® RAPID runs on the Biocartis Idylla™ platform and is CE Marked in Europe. The test has received FDA clearance in the United States for use in hospitalized patients suspected of sepsis.

About Immunexpress

Immunexpress is a molecular diagnostics company based in Brisbane, Australia, and Seattle, USA, dedicated to improving outcomes for patients with suspected sepsis. The company's SeptiCyte^® technology assesses a patient's dysregulated immune response by quantifying gene expression from whole blood, delivering actionable information during the critical early hours of sepsis evaluation. By enabling earlier and more confident clinical decision-making, Immunexpress aims to improve patient outcomes while helping reduce the economic burden of sepsis on healthcare systems worldwide.

For more information, visit https://immunexpress.com and follow Immunexpress on LinkedIn and X (Twitter).

Media Contacts:

David Schull
Russo Partners, LLC
[email protected] 

Juan Flores 
Russo Partners, LLC
[email protected] 

SOURCE Immunexpress, Inc.