CHICAGO--(BUSINESS WIRE)--Fitch Ratings has affirmed Universal Health Services Inc.'s (UHS) ratings, including the Issuer Default Rating (IDR) at 'BB+'. A complete list of ratings follows at the end of the release. The ratings apply to approximately $3.1 billion of debt at March 31, 2015. The Rating Outlook is Stable. KEY RATING DRIVERS --UHS has the strongest balance sheet in the for-profit hospital sector, with total debt-to-EBITDA of 1.9x at March 31, 2015. Fitch expects UHS to operate with