method for slow growing mycobacteria

Dear all,

We have a question about susceptibility loincs with the method “method for slow growing mycobacteria”

E.g. for isoniazide and minocycline etcetera

For these agents we can both find loinc codes with this method type but also loinctypes with the general MIC method

As far as I know the gold standard for slow growing mycobacteria is MIC

Now for minocycline I can somehow imagine that you might want to make a distinction between the normal MIC being measured for general bacteria or for rapid growth mycobacteria and the MIC measured in special mycobacteria laboratories for slow growth.

So can we use the following as a rule of thumb?

If an MIC is being measured for slow growing mycobacteria we have to chose loinc codes with “method for slow growing mycobacteria” eg 55156-4 for minocycline

And if an MIC is measured for rapid growing mycobacteria we simply use the standard code for MIC for general bacteria, eg 335-0 for minocycline

Even then, I wonder, wouldn’t it be possible to choose for the general code (eg 335-0) whenever an MIC is performed, regardless of slow or rapid growth?

In another segment of the laboratory report one can see the name of the species and thus it should be possible to infer that is concerns either rapid or slow growing bacteria.

Kind regards, Bram Lestrade

I just noticed this has been addressed before :slight_smile:


Hello Bram,

The key in a local system is whether there are different LIS entries for antibiotics used in typical MIC vs Slow growing MIC OR the system has the capability to use the order and antibiotic to store the different LOINC choices.

If there’s only one local code for Amikacin, whether it’s MIC, Kirby Bauer, Slow growing, etc then the site would need to use the methodless susceptibility term.

I’m very glad to see the past entries of the Forum are helpful!

Have a great day,


Lab LOINC Committee Chair