Association of the early absolute CD64-expressing neutrophil count and sepsis outcome

To evaluate the early absolute CD64/CD15/CD45 neutrophil count as a marker of prognosis of sepsis outcome the absolute CD64/CD15/CD45 count was measured by flow cytometry in 65 patients with confirmed or suspected Gram-negative sepsis and organ dysfunction. Serum interleukin(IL)-8 and interferon-gamma (IFNγ) were measured by an enzyme immunoassay. An absolute count lower than 2500 cells/mm³ could early discriminate non-survivors with sensitivity 82.9% (OR 3.46, 95%CIs 1.10-10.95, p 0.042). After forward step-wise Cox- regression analysis, it was found that acute coagulopathy, acute renal injury, and an early absolute CD64/CD15/CD45 count lower than 2500/mm³ were independently associated with unfavorable outcome. The OR for death among patients with an absolute CD64/CD15/CD45 neutrophil count greater than 2500/mm³ and circulating IL-8 greater than 95 pg/ml was 0.44; this was significantly increased to 7.44 among patients with an absolute CD64/CD15/CD45 neutrophil count lower than 2500/mm³ (p 0.045 by the Breslow-Day's test; p 0.046 by the Tarone's test). An absolute CD64/CD15/CD45 count below 2500/mm³ can be a useful prognosticator of sepsis outcome and a probable indicator of sepsis immunosuppression.