CHICAGO – The largest Catholic health system in Illinois has gained approval from the federal government to run a so-called “accountable care organization,” part of a program aimed at controlling costs and improving quality in Medicare.

Presence Health, formed in 2011 by the merger of Provena Health and Resurrection Health Care, will operate one of the five newly minted ACOs in Illinois announced Thursday by U.S. Health and Human Services Secretary Kathleen Sebelius.

Nationally, 106 new ACOs were announced, bringing the U.S. total to more than 250, officials said. That means 4 million Medicare beneficiaries will be assigned to an ACO.