Uric acid is not tested for on a DOT-regulated test. Labs conducting DOT testing can only perform the validity tests outlined in § 40.91 of the DOT regulations and apply the criteria for a "substituted" sample outlined in § 40.93 of the DOT regs:
http://www.dot.gov/ost/dapc/NEW_DOCS...IFR_200411.pdf
http://www.dot.gov/ost/dapc/NEW_DOCS...IFR_200411.pdf
These are the most current regs on the books.

Source: U.S. Department of Transportation / Office of the Secretary of Transportation