Quality control for microbiological culture media. Is it enough to follow the NCCLS M22-A2 procedures?

Abstract

Stringent quality control protocols must be used in order to guaranty that a particular medium is able to recover all sort of organism that may be present in clinical samples. Our aim was to evaluate an alternative protocol that would allow us to detect medium failure to yield quantitative growth of selected pathogens, and compare with the document M22-A2 from NCCLS. The detection limit of Haemophilus influenzae was significantly different depending on media source. We conclude that for some fastidious microorganisms, quantitative verification of the growth capacity of the culture medium is advised.