Endothelial Injury Signals Track DIC Worsening in Sepsis
Sepsis can move quickly from infection to vascular collapse, and disseminated intravascular coagulation often marks the point where that spiral becomes harder to reverse. In this prospective cohort of 324 patients with sepsis, biomarkers tied to endothelial injury rose alongside disseminated intravascular coagulation progression and, in some cases, short-term mortality. The pattern fits the biology of sepsis-associated coagulopathy: when the endothelium loses its barrier function, procoagulant signaling expands, microvascular flow becomes unstable, and platelet consumption can accelerate in parallel with organ dysfunction.
DIC progression was defined by a ≥1-point increase in the DIC score from day 1 to day 4. By that definition, 33.02% of the cohort progressed, while the 28-day all-cause mortality rate reached 25.00%. Those two outcomes did not unfold in isolation. They likely reflect the same underlying vascular injury, with endothelial disruption driving both clotting activation and impaired tissue perfusion.
Biomarkers of the Glycocalyx and Vascular Leak Rose with Progression
Four markers were measured in serum: heparan sulfate, hyaluronic acid, syndecan-1, and angiopoietin-2. Each of them points to a different piece of the endothelial injury response. Heparan sulfate and hyaluronic acid are components of the endothelial glycocalyx, a surface layer that helps maintain vascular integrity and regulate leukocyte and platelet interactions. Syndecan-1 is also a glycocalyx-associated marker, while angiopoietin-2 reflects endothelial activation and destabilization.
All four biomarkers were significantly elevated in patients who experienced DIC progression. In practical terms, the signal suggests that the clotting disorder in sepsis is not just a laboratory abnormality of coagulation factors and platelets. It is also a vascular disease, with measurable injury at the endothelial surface preceding or accompanying the worsening DIC score.
A single sentence captures the clinical tension: endothelial injury was visible in the blood before the coagulation phenotype fully declared itself at the bedside.
Syndecan-1 and Angiopoietin-2 Carried the Strongest Predictive Weight
After adjustment for platelet count, albumin, fibrinogen, and septic shock, multivariable logistic regression identified hyaluronic acid, syndecan-1, and angiopoietin-2 as independent risk factors for DIC progression. Heparan sulfate lost significance in that adjusted framework, which matters because not every endothelial marker contributed equally once major clinical confounders were accounted for.
The discriminative performance also separated the markers. The AUC was 0.607 for heparan sulfate, 0.599 for hyaluronic acid, 0.735 for syndecan-1, and 0.706 for angiopoietin-2. Those values place syndecan-1 and angiopoietin-2 in the more useful range for risk stratification, while heparan sulfate and hyaluronic acid showed weaker standalone discrimination. The message is not that one biomarker can replace clinical assessment. It is that some endothelial signals are more tightly coupled to the trajectory of coagulation failure than others.
Biologically, that makes sense. Syndecan-1 release marks glycocalyx shedding, which strips away a major antithrombotic surface and exposes the microcirculation to inflammatory and coagulation stress. Angiopoietin-2 destabilizes the endothelium further, increasing permeability and amplifying the vascular leak phenotype that often accompanies severe sepsis.
Platelet Count Showed a U-Shaped Relationship with DIC Progression
Restricted cubic spline analysis revealed a U-shaped association between platelet count and DIC progression, with both low and high levels linked to adverse outcomes. The low-platelet side is familiar in sepsis: consumption, sequestration, and impaired production can all accompany consumptive coagulopathy. The high-platelet side is less intuitive, but it may reflect an earlier inflammatory or prothrombotic state in which platelet activation is already underway even before overt depletion appears.
This is a reminder that a single platelet value does not tell the whole story in sepsis. Platelet count is useful, but it is also a moving target influenced by inflammation, endothelial activation, and thrombin generation. In a disease where clotting and bleeding can coexist, the trajectory of the platelet count may carry more information than the absolute number on a single day.
Mortality Aligned Most Strongly with Syndecan-1 and Angiopoietin-2
Multivariable Cox regression linked syndecan-1 and angiopoietin-2 independently to 28-day mortality. That finding is clinically important because it separates markers of DIC progression from markers of prognosis. Some biomarkers may identify patients whose coagulation score is worsening, while others may better capture the downstream consequences of vascular injury that translate into death within 28 days.
The distinction matters at the bedside. A biomarker that tracks DIC progression can help flag a patient who needs closer coagulation monitoring, while a marker linked to mortality may identify broader physiologic collapse beyond the clotting system. Syndecan-1 and angiopoietin-2 appear to sit closer to the center of that lethal endothelial phenotype.
What This Means for Sepsis Risk Stratification
The study supports a model in which endothelial disruption is not a passive bystander in sepsis-associated coagulopathy. Instead, it appears to be part of the mechanism that propels DIC forward. In that setting, biomarkers such as syndecan-1 and angiopoietin-2 could eventually complement standard laboratory assessment, especially when platelet count, fibrinogen, and clinical signs of shock do not fully capture the pace of deterioration.
There is a practical appeal to this approach. Sepsis patients often change rapidly, and DIC can evolve over a narrow window. Biomarkers that reflect glycocalyx shedding and endothelial activation may provide an earlier read on which patients are most likely to worsen, even before the full DIC picture is obvious.
Still, the findings do not justify immediate biomarker-driven management changes on their own. The cohort was prospective, but validation in independent populations is still needed before these markers can be treated as established decision tools. The study also shows association, not proof that changing endothelial marker levels will improve outcomes. What it does provide is a biologically coherent signal: endothelial injury, coagulation failure, and short-term mortality move together in sepsis, and syndecan-1 and angiopoietin-2 seem to capture that link most strongly.