A pilot study of a novel molecular host response assay to diagnose infection in patients after high-risk gastro-intestinal surgery
AimSeptiCyte LAB measures the expression of four host-response RNAs in blood to distinguish sepsis from sterile inflammation. Sequential monitoring of this assay may have diagnostic utility in patients at high risk for postoperative infectious complications.\n\nMethodsIn this pilot study we studied esophagectomy patients who had developed a complication within 30 days following surgery as well as a random sample of 100 uncomplicated postoperative patients. PAXgene blood samples were collected postoperatively and whenever a complication occurred. SeptiCyte scores (ranging 0-10 with increasing likelihood of infection) were compared to post-hoc physician adjudication of infection likelihood using strict definitions.\n\nResultsAmong 370 esophagectomy patients, 120 (32%) subjects developed a complication requiring ICU (re)admission, 63 (53%) of whom could be analyzed. Immediate postoperative SeptiCyte LAB scores were highly variable, yet similar for patients having a complicated and uncomplicated postoperative course (median score of 2.4 (IQR 1.6-3.3) versus 2.2 (IQR 1.3-3), respectively). Scores increased as complications developed, but this rise was higher for 34 subjects having confirmed infection (median difference 4.7 (IQR 4.1-5.8)) then for 12 subjects with a non-infectious complication (2.1 (IQR 0.4-3.6); p<0.0001). When 17 cases with undetermined infectious status were excluded, addition of SeptiCyte LAB to CRP resulted in improved diagnostic discrimination (AUC 0.88 (95%CI 0.77-0.99)) compared to CRP alone (AUC 0.76 (95%CI 0.61-0.91); p=0.04).\n\nConclusionsSequential measurement of SeptiCyte LAB may have clinical utility in surgical patients at high risk of postoperative infection, but its diagnostic performance in this setting needs to be further evaluated.