Detection of experimental bacteremia and fungemia by examination of buffy coat prepared by a micromethod.

Rabbits received intravenous injections of bacteria or fungi, and a comparison was made of the abilities of broth cultures, plating after dilution either in saline solution or in distilled water containing Triton X-100, and buffy coat examinations to detect the organisms in heart blood. The most sensitive method was broth culture. By microscopy or subculture of buffy coat cells prepared by centrifugation of blood in microhematocrit tubes, organisms were rapidly and regularly detected when their viable counts increased to 300--1,000/ml as detected by plating. By micromodification, buffy coat examination is technically easy to perform, and the method is only slightly less sensitive than when a larger amount of blood is used. Thus, it would be ideal for rapid provisional diagnosis of sepsis in patients, e.g., neonates, when the use of only a small blood sample is preferred.