I would stay quiet about it.

In the meantime, if they do find out about it, have a response ready.

Yes, I did have some credit problems in the past, however, I have since taking some major steps to improving my credit, etc. etc. "

In this day and age who doesn't have credit problems. However, since it is important in your field, have a specific response ready and make sure you convey the steps you have already taken to improve your credit situation.