Monthly Archives: June 2015

“In a world of its own…”

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Dermatophyte mycology I have always found a bit of a mystery, and even as a clinical microbiologist it has never really ignited my passion. All those microconidia and macroconidia are completely lost on me. I am comforted however by the fact that there are people within my laboratory who are excited by this subject and take pride in being good at it.

The thing which intrigues me about this area of microbiology is how long it takes to get a culture result from the skin scrapings and nail clippings….Nothing to do with the lab staff of course, that is just the way it is for this branch of microbiology, which has not changed much in decades.

Two weeks, three weeks and counting, with no real sign of this turnaround time coming down. (Maldi-tof of filamentous fungi may help a little in the future with regards to this.)

Having said this, I have never ever had a complaint from a clinician about the length of time it takes to produce a mycology result from a skin scraping or nail clipping, and this in itself says a few things to me about mycological culture and its clinical implications. In a smallish proportion of cases the culture result does have an impact on diagnosis and subsequent management of the patient, but this cohort of patients is small and generally as a group are not “sick” in the more traditional sense of the word.

As Bacteriology Automation systems begin to become commonplace, dermatophyte mycology is starting to become an increasingly isolated sub-speciality, requiring a different skill set from most of the other samples.

I sometimes wonder if all the skin scrapings and nail clippings in the country (what a thought!) should be packaged up and processed at the one laboratory. To be frank, a day transporting the samples makes little difference when your average turnaround time is three weeks…..

But then again, maybe not. I go back to my first paragraph, “some people are excited by this area”, and all clinical microbiology laboratories need people that are impassioned by their work…..

Michael

“Metafer: A Metaphor for the future….”

With the advent of automated bacteriology systems, it won’t be long before the majority of us are looking at digital images of agar plates as opposed to holding the plate in our hand.

But what about Gram stains, ZN stains etc?

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A few weeks ago, whilst wandering around the exhibition hall at the ECCMID conference in Copenhagen, I stumbled across this piece of apparatus, called Metafer. This system can automatically feed stains onto the microscope platform, then create digital images at different magnifications and from different areas of the slide. It will even automatically add oil when required…

Not only that, but the company is also developing interpretative software for preliminary analysis of the stain. This seems to be most advanced at present for AFBs on ZN stains and the software will collate anything suspicious looking for an AFB on  the slide and then display them as thumbnails on the screen for further checking/interpretation.

Such a system can now be interfaced with the advanced automation systems so that the digital images of the Gram stains can be viewed alongside the plate images.

The objectivity and standardisation of such a system is very appealing, along with the fact that the images can be stored indefinitely. Digital scanning and imaging of slides also has uses within the laboratory beyond microbiology.

I have no personal experience with using the Metafer platform or with the company that has developed it. There are probably other similar systems out there as well. However I imagine such systems will become commonplace over the next decade or so, and traditional “analogue” microscopes will soon die out…

Michael