Utility of the NEUT-RI and NEUT-GI Parameters of Sysmex XN 2000 in Acute Intestinal Bacterial Infections

Abstract Bacterial infections constitute a predominant factor contributing to morbidity and mortality; effective management of patients necessitates an accurate and timely diagnosis. To evaluate, in the early diagnosis of intestinal bacterial infection, the quantitative variations in the values of two parameters related to the functional state and the performance of neutrophils, called NEUT-RI (neutrophil-reactivity intensity) and NEUT-GI (neutrophil-granularity intensity), correlating them with white blood cells (WBCs), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and procalcitonin (PCT). A total of 57 intestinal bacterial infection–positive patients were retrospectively compared with 65 healthy subjects (control group). The identification of pathogens in fecal material samples was conducted through a molecular method, real-time multiplex PCR (FilmArray GI Panel BioFire, Biomerieux). WBC, NEUT-RI, and NEUT-GI were analyzed using the Sysmex XN 2000 hematology analyzer (Sysmex, Kobe, Japan). The Test-1 Alifax instrument was used to determine the ESR, while CRP and PCT were determined on the Beckman DxC AU 700 and Biomerieux VIDAS 3 instruments. Statistical evaluation was conducted employing Jamovi software. NEUT-RI and NEUT-GI were higher in subjects with intestinal bacterial infection, compared with healthy subjects: p < 0.001 and p = 0.002, respectively; in distinguishing subjects with infection from healthy subjects, NEUT-RI and NEUT-GI achieved both significant but moderate accuracy, with receiver operating characteristic area under the curve of 0.788 for NEUT-RI and 0.669 for NEUT-GI. The parameters NEUT-RI and NEUT-GI allow us to measure the activation state of neutrophils, which are key actors in the innate immune response. Based on the case series examined, they appear to support the diagnosis of bacterial intestinal infection with moderate efficacy.