%0 Journal Article
%T Quality control guidelines for testing gram-negative control strains with polymyxin B and colistin (polymyxin E) by standardized methods.
%A Jones RN
%A Anderegg TR
%A Swenson JM
%A  
%J J Clin Microbiol
%V 43
%N 2
%D Feb 2005
%M 15695708
%F 11.677
%R 10.1128/JCM.43.2.925-927.2005
%X An eight-laboratory study addressed the urgent need for quality control (QC) ranges for susceptibility determination when testing colistin (polymyxin E) and polymyxin B, two polycationic peptide antimicrobial agents, against multidrug-resistant gram-negative bacilli. For Escherichia coli ATCC 25922l, the QC ranges were as follows: for colistin, 0.25 to 1 microg/ml (11 to 17 mm), and for polymyxin B, 0.25 to 2 microg/ml (13 to 19 mm). For Pseudomonas aeruginosa ATCC 27853, the QC ranges were as follows: for colistin, 0.25 to 2 microg/ml (11 to 17 mm), and for polymyxin B, 0.25 to 2 mug/ml (14 to 18 mm). More than 97% of all reported QC results were within these proposed ranges.