If one person asks if another person is in our clinic and being treated, is it a HIPAA violation for a clinic nurse to acknowledge that the person is in fact there and being treated? The person asking was a co-worker of the person being treated but did not come in with the patient, nor did they say they were a co-worker, this is just known information by the nurse (we live in a very small town). And then the nurse offered to take the co-worker back to see the patient. Before entering the room, the nurse did knock and ask the patient if it was OK for the co-worker to come in but were the patient's rights violated by even admitting they were there and being treated?

This comes under the tiniest parts of HIPAA, which is mostly about transmission of data between medical facilities. Of course the nurse should have said 'Have a seat and I will see what I am at liberty to find out,' and talked to the patient before bringing the co-worker to the back. Presuming that the nurse suspected that the situation wasn't the sort of one that a patient would want to keep secret, and that this entailed suddenly leaving work and concerned people, and that the patient did indeed allow the co-worker in, I think it's a simple matter of making sure that there is policy in place for the future.

Yes it would be considered a violation. If reported, the nurse's supervisor should reprimand her at the least. If the patient complained, it could cause problems for the facility.

Basically, if you are a caregiver and someone asks you about a patient, you should not give ANY information without checking to make sure they are authorized to receive info.