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Comment by boneheadmed | Hacker News Reader

I think that what is termed "totally drug resistant TB" is more a matter of semantics as the article points out. I was in medical training in Southern California about 8 years ago and spent some time with a large county tuberculosis surveillance unit as part of a public health assignment. There were about five cases of then termed "multi-drug resistant TB" whereby the patients were either confined to their homes or an isolation unit in a hospital. They were under mandatory confinement and observation, enforceable by law. I had no idea that such cases existed at the time. I would refer people to this wikipedia article which has good information: http://en.wikipedia.org/wiki/Multi-drug-resistant_tuberculos...

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We've still got MDR-TB. But now we have XDR-TB (extensively drug-resistant TB) and TDR-TB (totally drug-resistant TB). Each less desirable to encounter than the last. TDR-TB seems to be the real deal: http://cid.oxfordjournals.org/content/early/2011/11/24/cid.c...

It's behind a paywall, but the gist is that some of these patients had TB resistant to ALL of the following:

isoniazid, rifampicin, ethambutol, pyrazinamide, and streptomycin (1st-line agents); as well as oﬂoxacin, moxiﬂoxacin, kanamycin, amikacin, capreomycin, para-aminosalicylic acid, and ethionamide (apparently 2nd-line agents).

Interestingly, the report doesn't discuss whether experimental/3rd-line treatments were tried (including my favorite from M2 year, linezolid). So it's possible that there's still something in our armamentarium that hasn't yet been tried (due, perhaps, to prohibitive cost). (And note that TB, and ID in general, is not my area of focus.)

I'm not up on my medical compounds, but how do the resistant strains respond to pre-penicillin compounds such as sulfa drugs and the like. Solfonamide: http://en.wikipedia.org/wiki/Sulfonamide_(medicine)

I've read, years ago, some speculation that these might be used to help beat down if not extinguish, an infection.

Seems that there was some work in this regards in the 1940s, but I don't see much since: http://chestjournal.chestpubs.org/content/8/6/166.abstract

The TB research community must know the state of the art, but I'm having a hard time finding it; I found some pubmed links supporting the use of sulfonamides, but nothing really since the 1940s. Not a lot of info about why these dropped off the map.

In the UK they use linezolid for drug resistant infections of all kinds. I think there have been a few cases of resistance already. In the dept I work they use tazocin as first line (it was considered second line til recently)

Without innovation we will have major problems within 20 years

Ah, very good. Yes the term XDR-TB makes more sense in the absence of knowing if every potential antimicrobial therapy has been exhausted. Always found it interesting that the last line therapy is lobectomy or pneumonectomy. TB is a terrible disease for which we will hopefully always stay a few steps ahead.

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