Figure 1.

Excessive uric acid in the blood (hyperuricemia) can originate from endogenous or exogenous sources. Various nutrients (purin-rich such as red meat or sugar-rich beverages) have been shown to be environmental (exogenous) factors participating in hyperuricemia; similarly intrinsic (endogenous) determinants from the host, like genetic defects affecting urate excretion, can also participate to hyperuricemia. Metabolism of elevated DNA concentration resulting from infections (exogenous) or cell cytotoxicity (endogenous) is also suspected to generate high levels of urate.