Tag Archives: bacterial identification

“The dying art of traditional microbiology”


I had the opportunity to visit a food microbiology laboratory a few weeks ago. It was clearly a good laboratory with excellent quality assurance measures, but it was interesting to visit a microbiology lab that did not have a MALDI-TOF platform in place. The lab still relied very much on traditional identification techniques for identification such as colonial morphology, Gram stain, oxidase, catalase, and of course the API biochemical strips!

This made me reminisce about my training days in microbiology in Glasgow back at the turn of the century, when we still used Kohn’s tubes for Salmonella & Shigella identification, X and V discs were used for Haemophilus influenzae, and the CAMP and Reverse CAMP test were used for Streptococcus agalactiae and Clostridium perfringens respectively.

Nowadays, in most clinical diagnostic microbiology labs, everything just gets “thrown” on to the MALDI-TOF platform and an ID is usually forthcoming. In the rare occasions that a “Maldi” ID is not obtainable, one can always send the isolate for 16s/18s RNA sequencing.

It is a changed world, and all the mystery has disappeared..

There are of course very good reasons for clinical microbiology labs to move to MALDI-TOF identification. It is fast, mostly accurate and cost-efficient when utilised in a mid to large sized laboratory. It is also probably safer in terms of risk of laboratory-acquired infections.

But it is a little bit dull, tedious even. I do miss the old-fashioned methods, their variety and their idiosyncrasies. It also gave staff a good grounding in the basic principles of microbiology and bacterial identification. Most new staff that start in medical microbiology laboratories these days will be unfamiliar with anything else apart from MALDI-TOF.

Traditional diagnostic microbiology is a dying art, and the labs that still practice it are becoming fewer by the year. 

I am by no means a luddite, and I am all for progress, but I don’t think the recent technological advances have necessarily made us better microbiologists, or made the job more enjoyable…