Hello!
Dear i agree for css you have to go through different medical tests and Lungs x ray specially. TB is a contagious disease so tests are important as it can spread easily. The medical board only checks your current medical health.The marks of Tb will be visible in the X ray but if you have gone through proper TB treatment (which is very lengthy process)your all other test reports will show that you are fit now. And they will have no objection. I have seen a few such cases among my colleagues. So do not worry and go ahead