Determination of bacterial growth activity and antibiotic sensitivity by

Abstract

A catalase method and apparatus are disclosed for direct measurement of bacterial growth activity in the presence and absence of antibiotics, and for the determination of antibiotic sensitivity directly from clinical specimens within one and one-half to four or five hours if the agent is a catalase producer. If not, antibiotic sensitivity is measured by light obscuration. The total bacterial counts of normal flora and artifacts in the growth medium do not affect the tests. Preferably, a transducer or other pressure-measuring technique determines the positive pressure produced by the catalytic decomposition of peroxide. Aerosolization of pathogenic organisms is avoided by combining hydrogen peroxide with a quaternary compound which kills the bacteria and at the same time frees additional catalase to yield total catalase titers which are very reproducible and accurate. The method and apparatus easily detect Staphylococcus, Pseudomonas, Proteus, E. coli, and other catalase-producing bacteria. The method and apparatus can be used to determine bacterial growth activity in many liquids for example, cutting oils, water used for drinking, pharmaceuticals, swimming pools, cooling towers and for other purposes as well as with body fluids both qualitatively and quantitatively.