Latent Tuberculosis and Isoniazid Prophylaxis.

[ZachR]

Wanted to ask if there are people here who were tested positive for LTB and underwent isoniazid prophylaxis and how did it feel?

I was tested negative for TB using a skin test, but later they did a fancy and very specific test called ELISPOT which came out positive where my doctor concluded that in his words 'you might be latently TB infected or have been exposed to TB'. That was in Feb this year and since then he has been pushing me to start a 9-month isoniazid monotherapy. However, I read the neurological side effects of the drug that are even more common in HIV-coinfection due to HIV's negative effect on the nerves and I am now very hesitant whether to start or not as there is a chance that I develop brain fog and neuropathy for 9months.. So, what is your experience and what do you recommend?

[Expat1]

I took it many years ago.  It is a very strong drug.  You really cannot drink alcohol as it screws up your liver if you do.   You need to take it with B vitamins (6 or 2) I forget.  Anyway, it is difficult to complete all 9 months. 

But is certainly beats getting TB.

There are 2 newer treatments a 1 month and a 3 month options.   They are called 1H and 3H.  I would go for that as 9 months is a very long time.   

I read somewhere that the chance of a latent TB infection turning into active TB was lifetime 10% in non HIV population but it is 10% per year if  HIV+.

Also even if treated for for latent TB, it can still reactivate.

I have a friend who just got over Pulmonary TB and he is still being tested for extra- pulmonary TB.

TB can affect other organs besides the lungs.

Here in Thailand, TB is the leading OI for people living with HIV/AIDs. And leading cause of death. 

It is also a really big pill.  Hope that helped.

Also the one pill a day for latent sure beats the 4,5, or 6 pills for active disease (which will also include the Isoniazid anyway) and for a lot longer.

[Expat1]

here is a good presentation on it:

https://www.who.int/tb/areas-of-work/tb-hiv/dooley_why_scale_up_short-course_rifamycin-based_regimens_ltbi_croi2018.pdf

And the treatments are called 1HP and 3HP.

[ZachR]

Thank you... the presentation is amazing!
The issue is that Biktarvy can't be administered with rifampin, rifapentine and the derivatives as they interact and reduce TAF and BIC levels. Otherwise..., even if it would be more toxic, I'd surely prefer a one-month regimen..
On the other hand, if one develops active TB they'll have to take 3 more drugs and get much more damaged... This is all profoundly depressing... really...

What was the prophylactic dose you took? And what were the side affects and did they resolve upon completion?

[Expat1]

300 mg per day for 9 months.   

If I had a few drinks the liver would cause a whole lot of pain. 

Not pleasant.

I would see about a replacement regiment for the one month and do the 1HP or 3HP if I had to do it all over again.

The 3 drug or 4 drug options have lots of very powerful drugs and some nasty side  effects (like possibly going deaf) etc.

Atripla seems to be the usual recommended ART with these drugs.  One advantage is that the Efavirenz should help metabolize the INH.  But I am not a doctor.  One month of Atripla plus the 1HP program seem doable (as I have taken both).  I didn't get bitchy crazy till about month 6 on Atripla.  And a month of strange tedious dreams seems not so bad as compared to 9 months of them.

[Expat1]

You need to take Pyridoxine 25 to 50 mg. With INH treatment.  That's the B vitamin.

[ZachR]

Thank you very much. I saw that the prophylactic dose is 5mg/kg for adults and 300mg max. In this scenario, for me it is around 4mg/kg, which is one of the lowest doses possible and least likely to cause major side effects. If I am a slow acetylator though, even this dose would be enough to cause side effects, so hope I am for once, a rapid acetylator. I don't think they will check my acetylation status, but, at the end of the day, I think the benefit seriously would outweigh the risk, given that I experience no major ill effects.

[ms3053]

When I tested Poz, I also had TB- I took the meds for 9 months. It wasn't all that bad. I did it and it helped.

[harleymc]

Going without alcohol for nine months is not a hardship.