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Latent tuberculosis while on aza

Prior to azathioprine exposure my Mantoux test was negative.
Today , two years after I am positive tested.
Has anyone experienced same situation and how has dealt with it ?
It's so overwhelming :(

my little penguin

Staff member
Latent tb
Needs to be treated by infectious disease doctor
They do a chest X-ray
Then isoniazid daily for 9 months
Simple as that
The isoniazid treats the latent tb
So at the end of 9 months no longer an issue
Thank you so much for the reply.
Is it possible to stay on azathioprine for my Crohn's while taking isoniazid ?
I was just about to switch to biologics.
G.i. told me to continue aza , until next week and wait for the quantifieron results.

my little penguin

Staff member
You can have false positives
So that is why they are waiting on the blood test
Most start biolgics after 1-2 months on isoniazid
Woth 8 weeks off biolgics as optimum time frame per the literature

Not sure on Aza ...
Quantiferon came backnegative.
My g.i. suggests that the positive Mantoux is due to BCG vaccination.
Pneumonologists on the other hand are really thoughtful about if I'm really suffering from Crohn's or from intestinal paratuberculosis 🙄🙄🙄🙄🙄
This is so frustrating.
They want me on a nine month regimen of isoniazid instead of the 3 month scheme (combo of isoniazid plus 2 antibiotics.)
I ve already had a right hemicolectomy and been on azathioprine for almost 2 years.
This is like a nightmare 🤐🤐🤐

my little penguin

Staff member
One negative test does not negate a positive one
They should have explained that
If you treat them if or when you need a biologic they can treat you safely provide the isoniazid protocol was completed
That's right the lung x-ray was also negative.
I have some doubts because the day the nurse's assistant measured my Mantoux I didn't feel the enduration , just the redness which is still apparent on my arm.
Now they think that it is possible not to have Crohn's.
The pneumonologists want me to undergo a colonoscopy and take biopsies suspecting that I suffer from intestinal tuberculosis and not Crohn's.
They said that if I fail humira , as long as I failed also azathioprine this could be the answer.
I feel a little hope inside my heart that I might get cured , but I'm afraid that I am only going to be disappointed

my little penguin

Staff member
Lots of folks who have Crohns
Eventually test postive for latent tb
Mainly due to the immunosuppressants/biologics
Please get a second opinion
Oh gosh, I ve been to 4 different pneumonologists so far.
They aren't even capable of telling me with responsibility whether I got latent Tb or not.
So far I got a negative quantiferon , but they say that it's sensitivity of accuracy of the negative results falls down by about 50% for those who are immunosuppressed , so it's not much of a reliable testing for the docs.
I repeated the Mantoux test , no induration at all , just measured again a redness of 15 mm cause I'm a special case as I am immunosuppressed, otherwise they wouldn't pay attention to the redness.
And as I wrote the other time there were no findings in the x-ray.
Today I am still taking isoniazid and I'm waiting for two more weeks to eventually be on humira.
They also said that the 9 month isoniazid treatment doesn't mean that I'm going for sure to get rid of those damn mycobacteriums for sure :/
Such a mess ! 😜😜😜😜

my little penguin

Staff member
Please see infectious disease doc
Quantiferon gold
Has markers
It tells you if immunosuppressed patients
Give a response or not based on those markers
So you can have a negative quantiferon test
But as long as It shows your body would show a response of exposed then it’s a valid test
If it shows your body won’t mount a response no matter what then an invalid test

So they can tell you if you have latent by or not
Good luck


Staff member
I think the confusion may be because you can have TB in your GI tract...that may be what they are referring to. And on biopsies, I believe TB and Crohn's look similar but there are differences.

We have always used the blood test - Quantiferon gold - after consulting several infectious disease doctors. My daughters have positive skin tests because they had the BCG vaccination. They always have a negative Quantiferon Gold test and negative chest x-rays and have never been treated for latent TB.
Good luck with your treatment. If you do have Crohn's, isoniazid has been shown in some studies to have a small benefit. So it may help with Crohn's as well as the TB.

I am wondering if it makes sense to have the BCG vaccine before starting Aza. It seems logical to have it, since Aza increases your chance of getting TB, so you may as well get some extra protection.

I ask because I may be starting Aza soon for the first time, and I've never had the BCG.
Thank you
I had the BCG vaccination during my childhood.
Discuss about any required vaccination with your doctor and make sure to get the labs for hepatitis , hiv etc before starting azathioprine
They are aware of my BCG and they didn't take it into consideration.
I'm just looking forward to be on the proper treatment for my Crohn's.
Azathioprine never put me in deep remission.
It's really important for me to achieve mucosal healing, I have already had a right hemicolectomy and a psoas abscess drained at 21.
Before this , I was suffering from pain alone in silence because no gastroenterologist ever mentioned the possibility of having ibd , until that emerged surgery who changed my life.
Now , I'm only 23 and I want to live a normal life.
Really hope that they will cure ibd in the future.


Staff member
Hang in there December's flower. I'm sorry they have given you so much trouble over this. If you had the BCG vaccine, then the skin test is useless. It will give you a positive result.

So you have had a positive skin test and NOTHING else is positive? The blood test is negative, the chest x-rays are negative? And they're still treating you for latent TB?

My daughter had the same results because of the BCG vaccine - they did the skin test and of course it was positive. But nothing else was positive so we were sent to an infectious disease doctor. We saw about 3 infectious disease specialists, ALL of whom agreed she did not have TB and did not need treatment.

She started Humira a couple months later...no issues.

Hopefully, Humira will be your miracle!
Yes , I had the skin test twice in fact , because I wasn't persuaded about the latent tb story.
They said that because I'm immunosuppressed I can catch the Tb even in the metro.
They claimed that my vaccination was a really long time ago , 15 years approximately , so it wouldn't justify the positives.
Quantiferon gold is negative and so does the X ray , but they say that it might be false negative due to the immunosuppression.
I'm still taking 3 pills of isoniazid once a day.
I am planning to visit an infectious disease doctor when I ll come back home to Athens cause I'm on holiday at the moment and most good doctors have also closed for summer until September

my little penguin

Staff member
Definitely see Infectious Disease
Quantiferon has a three part test
One is for the latent tb
Ther other two whether you can mount any response on the test to rule out false negatives

Hope it gets straightened out soon
Hi again just a quick update...
I tried to reach an infectious disease doctor but I didn't have any good chance with it is there wasn't any available appointment for the next 3 months...
So, I am just staying on isoniazid...
Visited my gastroenterologist yesterday to start humira, as I am on isoniazid for more than 34 days...
He now says that I need in total two months on isoniazid 😮😮😮😮, because they are afraid of the tb.
The Tb incidents in my country are rising high due to the refugees.
He shocked me !
The medical care practice, even if it's about Crohn's is so different across the world...
I thought the guidelines are Same
for all the doctors.
I really can't understand as a patient the necessity of waiting two months instead of 3 weeks before taking anti tnf in my case.
I can't see the point.
It is important that all the TB is eradicated before you start anti-TNF agents.

The anti-TNF agents will make it harder for your immune system to fight off any remaining TB.
TB can quite easily kill you if you are on anti-TNF.

TB is a tough bacteria to kill and I am not surprised at all that your doctor wants you to wait two months after starting isoniazid. Some guidelines suggest 3 months.

Are you on any other antibiotics as well as the isoniazid? This is usually given in combination with rifampin and a quinolone or macrolide antibiotic.

Are you on Azathioprine or any other Crohn's medication?

How are your Crohn's type symptoms at the moment?

Are you having regular blood tests for isoniazid induced liver damage? This is sometimes but not always recommended. Isoniazid can be quite toxic to the liver.
I am currently on azathioprine 200mg along with only isoniazid , isoniazid prescribed for 9 months.
Last colonoscopy in June showed disease recurrence on the anastomosis side , 8 apthus ulcers.
I am having all the blood tests on a monthly basis.
At first they said I just needed three weeks of chemoprophylaxis that's why I'm upset.

my little penguin

Staff member
8 weeks of isoniazid unfortunately is the norm prior to starting a biologic .
And then completely the full 9 months .

I am sorry you have to go through this

But they are being cautious for a reason
Tb mixed with anti tnf can be deadly

Lynda Lynda

I already "fired" my first Pulmonologist. Today I saw my second Pulmonologist and I don't have much confidence in him. I have Crohn's and take Humira and am newly diagnosed with latent TB. I have had two positive QuantiFERON blood tests, one ordered by my Gastroenterologist and one ordered by my PCP. Today I had a chest x-ray and a routine blood draw ordered by my new Pulmonologist. New Pulmologist wants to treat me with Riflamin ( ? ) once a day for 4 months, I don't know the dosage yet. He did not educate me one bit about Latent TB. I caught him by surprise when I asked him a question about medications used to treat latent TB. I also mentioned my Humira and he seemed unconcerned. I made an appointment to see my Gastroenterologist to discuss my latent TB treatment and my Humira. I surely wouldn't start gulping down antibiotics without having all the information I need so that I can properly advocate for myself. In the USA, what would be the most recommended and trusted treatment plan for adults for latent TB in 2021 ? All the postings here are 3 years old. Thank You for any information you can offer me.

my little penguin

Staff member
You need an infectious disease specialist at a university hospital.
They can tell you the latest treatments and handle latent tb cases as well as other diseases

Lynda Lynda

You need an infectious disease specialist at a university hospital.
They can tell you the latest treatments and handle latent tb cases as well as other diseases
Thank You. There is a University Medical Center here in my City and it is an in-network Hospital with my Health Insurance Company, so I should be able to find the kind of Specialist I need to effectively treat my Latent TB.

Lynda Lynda

My new Pulmonologist : Prescribed Rifampin 300mg twice a day for 4 months. My current Gastroenterologist : His Family Nurse Practioner ordered the QuantiFERON blood test a short while ago and it came back positive. I saw him recently. He tells me to continue taking my weekly Humira Injections while I am taking the Rifampin. He is not familiar whatsoever with Rifampin. My Pulmonologist is disinterested in my Crohn's Treatment and my Gastroenterologist is disinterested in my Latent TB treatment. Because I have an important blood draw tomorrow, I will start taking the Rifampin this Friday. This is what I am going to do. My energy has been totally depleted by trying to deal with my many doctors, their staff and my Health Insurance Company regarding several different issues. The stress is overwhelming me and affecting my mental health. I can do no more. I'm so tired. Take Care.
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