I don't know how your son is being treated, but in my case for even latent TB I should be on at least two, usually four these days, antibiotics because it is such a resistant bug. The big problem is that doctors seem afraid to give a high dose--there are many reasons why that are arguable--but if they give a long dose that is too low, the bacteria become more resistant. This is what they did with my throat infection the second time. For me, even 1000 mg of Penicillin is not strong enough to put my recurring infection back in the box, let alone kill it altogether. The doc in the ER who treated me for my pelvic/UTI infection gave me stronger drugs.
In the case of TB, it enters the body usually through the lungs though it can come in other ways and be harder to trace. It looks for any small scars you may have anywhere in your body, liver, spleen, anywhere, and it settles in them and forms a waxy coating over itself to protect itself from attack. This coating also keeps it somewhat dormant while your immune system is constantly attacking it. It then begins to form a calcified coating over itself, making it even harder, if not impossible to treat. Calcified lymph nodes can be removed surgically, then decalcified and biopsied to determine what kind of infection exactly resides inside. But the ENT has to be very very very good because if looking at some salivary glands the infection doesn't form gnaulomas (people think TB or other similar infection=granuloma always, but exists in lympocytic infiltrates. For me, the lymph nodes are calcified in various parts of my body near pain and vitiligo sites and were mapped on a full spine xray as well as gallium scan, which showed areas of infection.
Perhaps you could persuade your doc to give your son a gallium scan if it is safe for him, to determine where the hot spots still are, if any. It is also a good baseline for spreading, especially if he may have cancer risk which we all seem to have. The gallium picks up any infection. This might help you make a case for stronger or continuation of antibiotics. Also, if he has some calcified/inflamed lymph nodes, you might talk about a thorough needle biopsy or in some cases removal.
Hopefully, docs will realize that if the infection does affect the lymph nodes, it can cause a problem even after calcification--which is also a precancer stage--and removal and proper evaluation to find the right bacteria and the right antibiotic treatment can help.
I would fight for better whole body evaluation and treatment. That gallium scan really made my docs not only believe that I was ill all over, but to know where I'm really having trouble. If it spreads, they will see it on the next one. The xray was good too, though a good reader may see that stuff on the gallium scan too, because you can see bone.
I'm so glad you found a good place and are doing this because I think it will really help him. You are a good mom!
--Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us. Bill Watterson (1958-) cartoonist "Calvin and Hobbes"
Ills--Sjogrens-Lupus-like AI Disease, Hashis, Vitiligo, spinal stenosis/fusion with plate, salivary/lymphectomies, Diabetes, NAFLD, COPD, RLS, neuropathy, trigonitis, hystero, diffuse brain atrophy, GI nightmare
Meds--Plaquenil, Evoxac, Metformin, Synthroid, HCTZ, Estradiol patch, Prosed, Detrol, Klonopin, Ultram, Vicodin, Restasis, Albuterol, steroid injections and pred prn