1. < MAC & Bronchiectasis

NTMs in sputum samples: is it really reliable for therapy monitoring?

Posted by mary80 @mary80, Nov 8 9:04am

I've learned that Mycobacteria are ubiquitous and can be detected even in healthy people, that's why two positive samples as well as clinical and radiological criteria are required to establish a disease diagnosis.
But if so I wonder why sputum monitoring is used to evaluate response to treatment and to take therapeutic decisions.

I'll give you a pratical example: a patient with a confirmed diagnosis of mycobacteriosis who is undergoing therapy (big 3), starts taking monthly tests to check for negativity. The first 4 sputum results are negative. CT scan has improved but the fifth sample is positive again and doctors decide to add Amikacin.

Do you think this approach is correct?

How do you determine that the fifth sample has clinical significance? If it remains an isolate relief, couldn't it simply be transient, like what could be found in healthy people?
On the other hand I wonder if it's really so common to find mycobacteria in healty people. Many people with bronchiectasis undergo periodic sputum checks and never test positive for mycobacteria throughout their lives (most of them).

Thanks for any of your contributes.

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mokie | @mokie | Nov 10 10:17pm

Does anyone know a trick for getting a sputum sample? (Or could someone help me find the answer if it has already been posted somewhere. I'm not great with technology.)

I am having trouble getting a sputum sample for my doctor. I was diagnosed in around 2015 with NTM, and developed cavities and nodules. To monitor my condition, the doctor needs more sputum samples. 1 sample showed no MAC following months of treatment with amikacin, ethambutol, rifabutin, and clofazimine, and the 2nd sputum also has no MAC showing, but it was given after I nebulized saline, so doc didn't know if that would be a true reading (saline may kill micro- bacterium). I don't cough stuff up until after I nebulize, and sputum produced that way may give a false reading.
Best regards to all of you battling this illness!

Mokie

REPLY
2 replies
reneemc | @reneemc | Nov 11 11:03am
In reply to @mokie "Does anyone know a trick for getting a sputum sample? (Or could someone help me find..." + (show)
@mokie

Does anyone know a trick for getting a sputum sample? (Or could someone help me find the answer if it has already been posted somewhere. I'm not great with technology.)

I am having trouble getting a sputum sample for my doctor. I was diagnosed in around 2015 with NTM, and developed cavities and nodules. To monitor my condition, the doctor needs more sputum samples. 1 sample showed no MAC following months of treatment with amikacin, ethambutol, rifabutin, and clofazimine, and the 2nd sputum also has no MAC showing, but it was given after I nebulized saline, so doc didn't know if that would be a true reading (saline may kill micro- bacterium). I don't cough stuff up until after I nebulize, and sputum produced that way may give a false reading.
Best regards to all of you battling this illness!

Mokie

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The saline can alter the sputum test results?

REPLY
scoop | @scoop | Nov 11 11:36am
In reply to @mokie "Does anyone know a trick for getting a sputum sample? (Or could someone help me find..." + (show)
@mokie

Does anyone know a trick for getting a sputum sample? (Or could someone help me find the answer if it has already been posted somewhere. I'm not great with technology.)

I am having trouble getting a sputum sample for my doctor. I was diagnosed in around 2015 with NTM, and developed cavities and nodules. To monitor my condition, the doctor needs more sputum samples. 1 sample showed no MAC following months of treatment with amikacin, ethambutol, rifabutin, and clofazimine, and the 2nd sputum also has no MAC showing, but it was given after I nebulized saline, so doc didn't know if that would be a true reading (saline may kill micro- bacterium). I don't cough stuff up until after I nebulize, and sputum produced that way may give a false reading.
Best regards to all of you battling this illness!

Mokie

Jump to this post

@mokie @reneemc An induced sputum sample is done in office if someone has a difficult time producing a sputum sample. 7%+ saline is generally used. So I would think that the hyper saline does not change the sputum significantly. My understanding for monitoring MAC et al., comes down to not only frequent sputum samples but also radiology (CT scans) and clinical symptoms.

7% saline by itself does not kill pathogens but it creates an environment that makes it harder for bacteria to thrive. Inhaled saline helps with clearance, which reduces bacterial load. The bacteria are sneaky and can form biofilms making them resistant to antibiotics. So the more bacteria you can get rid of frequently the better.

REPLY
1 reply
mokie | @mokie | Nov 11 6:08pm
In reply to @scoop "@mokie @reneemc An induced sputum sample is done in office if someone has a difficult time..." + (show)
@scoop

@mokie @reneemc An induced sputum sample is done in office if someone has a difficult time producing a sputum sample. 7%+ saline is generally used. So I would think that the hyper saline does not change the sputum significantly. My understanding for monitoring MAC et al., comes down to not only frequent sputum samples but also radiology (CT scans) and clinical symptoms.

7% saline by itself does not kill pathogens but it creates an environment that makes it harder for bacteria to thrive. Inhaled saline helps with clearance, which reduces bacterial load. The bacteria are sneaky and can form biofilms making them resistant to antibiotics. So the more bacteria you can get rid of frequently the better.

Jump to this post

Thank you so much @reneemc

It makes sense that if they use 7% saline (which is what I am on) to produce sputum, the sample produced is legitimate.

I am grateful to you for taking the time to help!

Mokie

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