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. 1986 Jun;23(6):997–1000. doi: 10.1128/jcm.23.6.997-1000.1986

Influence of technical factor variations on serum inhibition and bactericidal titers.

B F Woolfrey, R T Lally, K R Tait
PMCID: PMC268779  PMID: 3486883

Abstract

The influence of technical factor variations on serum bactericidal and serum inhibitory titers was studied by using Staphylococcus aureus clinical isolates versus oxacillin-spiked human serum. Parallel tests, both with and without the use of beta-lactamase in count plates to inactivate oxacillin carryover, were performed with a conventional macrodilution approach, a carefully controlled macrodilution procedure, and a standard microdilution method. Careful control of technical factor variations diminished the incidence of low serum bactericidal titers and decreased the dispersion of results, a finding corollary to the known influence of technical factor variations on the measurement of MBCs. The incorporation of beta-lactamase into count plates resulted in a shift of serum bactericidal titers to lower values. The microdilution method appeared to be least influenced by technical variations and, with the addition of beta-lactamase to count plates, provided the best results.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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