Neutropenic sepsis is associated with distinct clinical and biological characteristics: a cohort study of severe sepsis

Immunocompromised patients who develop sepsis while neutropenic are at high risk for morbidity and mortality; however, it is unknown if neutropenic sepsis is associated with distinct clinical and biological characteristics. We conducted a prospective cohort study of patients admitted to the medical intensive care unit of an academic medical center with severe sepsis. Patients were followed for the development of acute respiratory distress syndrome (ARDS), acute kidney injury (AKI), and mortality. Plasma proteins, representing the host inflammatory response, anti-inflammatory response, and endothelial leak were measured in 30 % of subjects. Clinical characteristics and plasma protein concentrations of patients with neutropenia at enrollment were compared to patients without neutropenia. Of 797 subjects enrolled, 103 (13 %) were neutropenic at ICU admission. The neutropenic subjects were more often in shock, admitted from the hospital ward, had higher APACHE III scores, and more likely bacteremic. Neutropenia was an independent risk factor for AKI (RR 1.28; 95 % CI 1.04, 1.57; p = 0.03), but not ARDS (RR 0.90; 95 % CI 0.70, 1.17; p = 0.42) or 30-day mortality (RR 1.05; 95 % CI 0.85, 1.31; p = 0.65). Neutropenic subjects had higher plasma interleukin (IL)-6 (457 vs. 249 pg/ml; p = 0.03), IL-8 (581 vs. 94 pg/ml; p