Quality control limits for microdilution susceptibility tests with norfloxacin

Abstract

A multilaboratory study was designed to define quality control limits for microdilution susceptibility tests with norfloxacin. The following limits were proposed: for Escherichia coli ATCC 25922, 0.03 to 0.125 .mu.g/ml; for Pseudomonas aeruginosa ATCC 27853, 1.0 to 4.0 .mu.g/ml; for Staphylococcus aureus ATCC 29213, 0.5 to 2.0 .mu.g/ml; and for Streptococcus faecalis ATCC 29212, 2.0 to 8.0 .mu.g/ml. The latter represents a change in the previously recommended control limits.