Mixed MAC infection; Bronchiectasis exacerbation
My husband Bruce, the MAC man, had a CT scan last week. Last one was in December 2021 when his lungs had improved from June 2021. This latest CT indicates multiple cavitary lesions where before he only had one.
Five monthly sputum culture results to date were 3 with no MAC, 1 with MAC, latest with no MAC.
Doctors did drug sensitivity analysis on the positive sputum culture and discovered that at least one of the big 3, Rifampin, didn't work. It is being switched out for Azithromycin, which didn't pass susceptibility testing early on.
Doctors suspect a mixed MAC infection and also that Bruce's Bronchiectasis is flaring. For the latter he is on a 14 day regimen of Amoxicillin.
Is this an unusual track to take for MAC? I know it's a hard bacteria to eradicate especially with Bronchiectasis but it seems like with all the daily antibiotics plus nebulized Arikayce, the poor guy should be getting some relief.
Observations, advice, comments welcome.
Thank you all for your MAC expertise.
Melissa
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Hi Melissa. I am so sorry to hear that Bruce is having such a hard time managing his MAC. Do you have a copy of that susceptibility test and know what meds are listed? When he is on these antibiotics, is it long term?
Hi Terri,
The antibiotics are supposed to be long term, 12 to 18 months, although a number of changes and modifications have been made since he started treatment in September 2021. A work in progress.
We do have a copy of the susceptibility tests. Not all of the drugs that Bruce is taking were tested. Oddly Rifampin has the same sensitivity number both times.
The first round of testing was done on a culture from August 2021 and the second on one from March 2022, when he tested positive again for MAC after 3 negatives.
The list includes some drugs with factors of S (Susceptible), I (Intermediate), R (Resistant) :
Drug Test 8/9/21 Test 3/19/22
*Amikacin 16 32
Ciproflaxin 8 >8
Clarithromycin 16 I 2 S
Linezolid 32 R 32 R
Moxifloxacin 4 R 4 R
Rifabutin <=0.25 0.5
*Rifampin 4 4
Streptomycin 64 32
Bruce is on the two starred drugs, Rifampin and Amikacin, the latter of which he takes in a nebulized form (Arikayce). He is also taking Clofazimine and Ethambutol.
Earlier in the week he began the 14 day course of Amoxicillin/Clavulanate (Augmentin) to reduce the suspected Bronchiectasis flare.
Thoughts?
Melissa