A pilot study of a novel molecular host response assay to diagnose infection in patients after high-risk gastro-intestinal surgery

Abstract

PURPOSE: SeptiCyte LAB measures the expression of four host-response RNAs in peripheral blood to distinguish sepsis from sterile inflammation. This study evaluates whether sequential monitoring of this assay has diagnostic utility in patients after esophageal surgery. MATERIALS AND METHODS: Patients who developed a complication within 30 days following esophageal surgery and a random sample of 100 patients having an uncomplicated course. SeptiCyte LAB scores (ranging 0-10 reflecting increasing likelihood of infection) were compared to post-hoc physician adjudication of infection likelihood. RESULTS: Among 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). In a direct comparison of patients developing a confirmed infectious (n = 34) and non-infectious complication (n = 12), addition of SeptiCyte LAB to CRP improved diagnostic discrimination of infectious complications (AUC 0.88 (95%CI 0.77-0.99)) compared to CRP alone (AUC 0.76 (95%CI 0.61-0.91); p = .04). CONCLUSIONS: Sequential measurement of SeptiCyte LAB may have diagnostic value in the monitoring of surgical patients at high risk of postoperative infection, but its clinical performance in this setting needs to be validated.