Bill's answer is correct. If it says inmate than they were a patient at the hospital. But it is not limited to TB. They were there because of longterm illness, weather it be physical or mental.
The ones that were nuns ran the place. St. John's is still there but is no longer a true hospital. People in the neighborhood fought for the Emergency room to stay open. But now pretty much a medical center. There are no long term patients there.