PURPOSE:Sepsis is an acute inflammatory response to an infection, leading to systemic illness and organ dysfunction. Mechanisms that lead to death in sepsis include alterations in vascular wall function, which contribute to organ dysfunction. Maintenance and repair of the vasculature is partially mediated through recruitment of endothelial progenitor cells (EPCs) from the bone marrow. However, the role of EPCs as a biomarker for organ dysfunction, a major determinant of mortality, in sepsis is unknown. We sought to determine the predictive value of quantitative EPC measures for the development of sepsis-related organ dysfunction (measured by organ-specific Sepsis-related Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation (APACHE) II score) and mortality.
METHODS:Patients who met the diagnostic criteria for sepsis, severe sepsis, and septic shock were enrolled and peripheral blood was obtained within 72 hours of meeting criteria for this disorder (baseline) and on days 7, 14, and 28. EPCs were identified as CD45(-)CD34(+)VEGFr2(+)CD133(-) using a multi-color fluorescence activated cell sorting (FACS) analysis.
RESULTS:We enrolled 27 patients with sepsis and sepsis-related organ dysfunction. The mean age of our patients was 44.4 years with 55.5% being male. The majority of our patients were African-American with a sepsis-related diagnosis of pneumonia. We found that increased circulating EPCs positively correlated with shock as assessed by higher cardiovascular SOFA scores (p = 0.001). Increased number of EPCs were also significantly associated with decreased 28-day survival (p = 0.01). Although there was a trend towards increasing number of EPCs correlating with total SOFA scores (p=0.09), significant associations were not found between circulating EPCs and APACHE II scores (r2= 0.01, p=0.59), ICU or hospital length of stay (p=0.65 and p=0.50 respectively).
CONCLUSION:Although, increased number of EPCs positively correlated with increasing shock and mortality, further studies are needed to further define the role of EPCs in sepsis patients and to delineate the prognostic implications of these cells.
CLINICAL IMPLICATIONS:EPCs may be a valuable marker to predict clinical outcome in patients with sepsis.
DISCLOSURE:Sushma Cribbs, None.