Unfortunately, a great number of the factory bred gouramis are riddled with TB, they seem more susceptible to it then a lot of other families. Normally, as with many "diseases", the immune system keeps it in check, however, if the fish gets stressed, it can break out and in some cases overwhelm and destroy the fish.
There are other causes for erruptive ulceration, as always, it is difficult to be sure with careful observation, the pictures are really not clear/close enough, (it would require special techniques anyway). Broad spectrum anti-bacterial agents and good conditions will often help the fish get these bacterial agents under control without the need to escalate to Kanamycin or similar.
In cases where TB is a possibility, you should avoid contact with the water if you have any cuts or scratches, and in any case, wash well afterwards. Fish TB can be contracted by humans, but it is uncommon, so paranoia is not required. If you do get unexplained illness, or similar erruptive lesions on you skin, particulaly the hands and arms, (and not just spots!!! - things that stay open without help for a week or more!!!), it is worth showing your doctor and mention that infection with Mycobacterium marinum is a possibility, the regular test for human TB does not necessarily detect that, (human TB is caused by Mycobacterium tuberculosis).