CHICAGO--(BUSINESS WIRE)--Fitch Ratings has upgraded the rating on approximately $183.6 million of bonds issued by the State of Ohio on behalf of Summa Health System (Summa) to 'A-' from 'BBB+'. The Rating Outlook is revised to Stable from Positive. SECURITY Bond payments are secured by a pledge of the accounts and general intangibles of the obligated group. KEY RATING DRIVERS SOLID LIQUIDITY: The upgrade to 'A-' reflects Summa's solid liquidity, light debt burden and solid coverage metrics. Wi