Attached is the Death Certificate. She dies at age 32, so assuming she married at age 18, the marriage would be 1923 or after.
I see a John Katitus in the 1940 census as a lodger in the City of Pittsburgh. He is a chef. (don't know if it's him or not.)
I'd be looking in Allegheny County for the marriage.
Any idea on religion? The church may have a record if you can find that.