Plasma interleukin-8 (IL-8) interleukin-10 (IL-10), and E-selectin concentrations were studied in 39 neutropenic and 30 non-neutropenic bacteremic patients; 54 nonbacteremic patients were analyzed as controls. Interleukin-8 concentrations were significantly higher in neutropenic than in non-neutropenic bacteremic patients (median 475 vs. 0 pg/ml, p < 0.0001). Median IL-8 and IL-10 levels were higher in bacteremic than in non-bacteremic patients (330 vs. 0 pg/ml, p < 0.0001 and 20 vs. 0 pg/ml, p = 0.04, respectively). In contrast, concentrations of IL-10 were similar in neutropenic and non-neutropenic patients. Median levels of E-selectin were not increased in any of the patient groups. Neutropenic bacteremic patients showed significantly lower concentrations of E-selectin than did non-neutropenic bacteremic patients (p < 0.0001). In conclusion, neutropenic bacteremic patients had significantly higher concentrations of IL-8 than non-neutropenic bacteremic patients. Levels of IL-10 were higher in bacteremic than in nonbacteremic patients, but neutropenic and non-neutropenic patients had similar levels of IL-10. Increased levels of E-selectin were not found in any of the patient groups, although neutropenic patients with bacteremia had lower concentrations than did non-neutropenic patients.