Survival and function of phagocytes in blood culture media

The survival and function of human phagocytes in sterile aerobic and anaero bic blood culture media were investigated using neutrophil morphology, whit e blood cell count in a haemoanalyser, flow cytometry, oxidative burst resp onse, and bactericidal effect in Colorbact(R) and Septi-Chek(R) blood cultu re media and Bact/Alert(R) When comparing agitation to stationary incubatio n no difference in phagocytic activity was found. The methods showed the sa me trends demonstrating that the phagocytes' viability and activity were pr olonged by oxygen and shortened by anaerobic conditions and sodium polyetha nol sulfonate (SPS). Best preserved activity and viability were found in th e aerobic media containing less than 0.5 g/l SPS, in which significant phag ocyte oxidative burst and bactericidal activity were found up to 4 days aft er inoculation. Considering that the majority of bacteremias are due to aer obic or facultatively anaerobic bacteria, the present data suggest that mos t bacteria may be recovered by the use of one aerobic bottle with SPS conce ntration below 0.5 g/l to protect meningococci and other SPS-sensitive bact eria and one above 0.5 g/l to stop phagocytic activity, plus one anaerobic bottle with SPS below 0.5 g/l.