Quantitative Assessment of Significant Hematological Parameters Deviation from Healthy State for Sepsis Clinical...

Sepsis, a life-threatening condition, requires improved diagnostics and severity assessment. Based on long-term clinical observation, Hemoglobin (Hb), lymphocyte percentage (Lymph%), and platelet distribution width (PDW) change significantly during sepsis. This study aimed to evaluate these three Complete Blood Count (CBC) parameters for distinguishing sepsis patients from healthy individuals and to develop a novel quantitative metric based on their combined deviation from a healthy state to assess sepsis severity. This retrospective case-control study included 496 sepsis patients (diagnosed according to Sepsis-3 criteria upon admission) and 1136 healthy controls. Initial Hb, Lymph%, and PDW were z-score standardized. The healthy cohort's 3D centroid was calculated and each sepsis patient's Euclidean distance from this centroid was computed. Group differences and correlation with SOFA scores were analyzed. 3D scatter plots visualized these relationships. Hb, Lymph%, and PDW differed significantly between sepsis patients and controls (p < 0.001), with sepsis showing lower Hb/Lymph% and higher PDW. The calculated Euclidean distance from the healthy centroid was significantly greater in sepsis patients (p < 0.001). This distance strongly correlated with SOFA scores (r = 0.45, p < 0.001) and was larger in patients with higher disease severity. 3D visualization confirmed group separation, with color intensity reflecting this distance and correlating with increasing deviation from the healthy centroid. The Euclidean distance of key CBC parameters from a healthy cohort's centroid effectively quantifies deviation from a healthy state and correlates with disease severity. This approach using routine CBC data offers a promising, simple tool for sepsis severity assessment and monitoring.