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.

Think before use: Sterility checking of culture plates

“…As per the present study, it was suggested to prepare the culture media and utilize the plates freshly. Maintaining the plates in low temperature sometimes enhance the growth of psychrophilic organisms [9,[16][17]. Thus each and every laboratory has to analyze and validate the shelf life of the prepared agar plates, otherwise dryness leads to the plates useless.…”

“…The quality of the culture media preparation without contaminations is primarily depend on the quality of the raw materials including petri dishes, chemicals used for media preparation, additive like whole egg, blood, serum etc. and, water [17]. If these parameters are analyzed properly means, then the chance of getting contamination may reduce to 50%.…”

Culture media for clinical bacteriology in low- and middle-income countries: challenges, best practices for preparation and recommendations for improved access

“…According to references[8,13,23,24,29,[56][57][58][59].Abbreviations: ATCC = American type culture collection, EQA = external quality assessment, QC = quality control…”