Altered uric acid levels and disease states.

Altered serum uric acid concentrations, both above and below normal levels, have been linked to a number of disease states. An abnormally high uric acid level has been correlated with gout, hypertension, cardiovascular disease, and renal disease, whereas a reduced uric acid concentration has been linked to multiple sclerosis, Parkinson's disease, Alzheimer's disease, and optic neuritis. Historically, uric acid has been considered a marker of these disease states. Recent studies, however, have provided evidence that uric acid may actually play a role in the development or progression of such diseases. As a result, the manipulation of uric acid concentrations is now either included in, or being investigated for, the treatment of a variety of disease states.