A-151 Evaluation of Monocyte Distribution Width as an Early Marker for Diagnosis of Sepsis
Authors: Park J , Kang J , Choi Y , Choi H , Shin M 
Published: September 2023

Abstract

Background
Since sepsis has a high mortality rate, early diagnosis and treatment can increase the survival rate and improve prognosis. However, it is difficult to diagnose sepsis accurately in actual clinical practice. Determination of Procalcitonin or C-reactive protein (CRP) levels, which are conventionally used for diagnosing sepsis, are time-consuming. Recent studies have shown that monocyte distribution width (MDW), which is observed simultaneously during the complete blood count (CBC)/diff test in Beckman Coulter DxH900, is a potential marker for the early detection of patients with or developing sepsis. This study evaluated MDW for early detection of sepsis in patients visiting the emergency department.

Methods
This study enrolled a total of 1167 patients (&gt;18 and ≤80 years of age) who visited the emergency department of a single institution from August 4, 2020 to March 31, 2021, whose initial evaluation included CBC with differential tests and other blood tests (CRP and Procalcitonin). Samples for CBC and MDW were collected in K3-EDTA tubes and analyzed in a UniCel DxH 900 analyzer (Beckman Coulter, Inc., USA). Sepsis was diagnosed according to the sepsis-3 definition through a medical record review. All patients were grouped into no sepsis, sepsis, and septic shock. The diagnostic performance of MDW and other biomarkers for the detection of sepsis was evaluated through statistical analysis. The subgroup analysis for diagnostic performance was performed in subjects with malignancy or without malignancy. All statistical analyses were carried out using Analyze-it, and P &lt; 0.05 was considered statistically significant.

Results
Of the 1167 patients enrolled, 156 patients (13.4%) were diagnosed with sepsis (135 (11.6%) sepsis and 21 (1.8%) septic shock). Among sepsis patients, those with positive culture results were 46.8%, and the rest either had negative culture results (43.6%) or did not proceed with culture testing (9.6%). The MDWs of the no sepsis group, sepsis group, and septic shock group were 19.70, 27.20, and 31.10, respectively, CRPs were 1.82 mg/dL, 8.84 mg/dL, and 20.44 mg/dL, and Procalcitonins were 0.19 ng/mL, 1.72 ng/mL, and 18.20 ng/mL (median, P &lt; 0.0001). All biomarkers showed a higher value in the sepsis group compared to the no sepsis group. Median MDW showed an increasing trend in patients with malignancy and without malignancy. The AUC of MDW, WBC, CRP, and Procalcitonin for the prediction of sepsis were 0.869, 0.604, 0.773, and 0.868, respectively (P &lt; 0.0001), thus MDW and Procalcitonin showed similar diagnostic performance. At the cutoff of MDW (21.5), the sensitivity was 91.0% and the negative predictive value (NPV) was 98%. The diagnostic performance of MDW showed similar results in cancer patients and cancer-negative patients (AUC 0.873 vs 0.869).

Conclusions
MDW, which is automatically measured in Beckman Coulter DxH900 hematology analyzer without the requirement of additional reagents during CBC/diff test, has high accuracy in detecting patients with sepsis and could be a reliable tool for early detection of patients with sepsis in the emergency department compared to results of culture or other biomarkers which take longer time to get the result. Furthermore, high NPV may help clinicians rule out sepsis.