Clinical evaluation of a lysis-centrifugation technique for the detection of septicemia

M. T. Kelly, M. F. Fojtasek, T. M. Abbott, D. C. Hale, J. R. Dizikes, R. Boshard, G. E. Buck, W. J. Martin and J. M. Matsen

A commercially available lysis-centrifugation blood culture system was compared with a two-bottle broth-culture system employing 100 mL of broth and 10 mL of blood per bottle to analyze 1,913 blood specimens. Of 154 clinically significant isolates, 89% were detected by the lysis-centrifugation technique, and 73% were detected by the broth-culture method. Twenty-seven percent of the organisms were detected only by the lysis-centrifugation technique, and 11% were detected only by the broth system. Fifteen polymicrobial cultures were encountered; the lysis-centrifugation technique detected 93% of the organisms in these cultures, while the broth-culture method detected only 20%. Isolated colonies of clinically important organisms were available 30 hours earlier with the lysis-centrifugation technique. These results suggest that the lysis-centrifugation technique may provide a substantial improvement over conventional methods for blood cultures.