Measuring sUA Levels

  • sUA levels are often normal during a flare, so measurements should be made at least 2 weeks post flare.

Consider the following:

  • In the Urano study, sUA levels during the acute attack were normal in 49% of patients. The mean levels of sUA in these patients during the acute gout attack (7.5 +- 1.4 mg/dL or 450 mol/L) were significantly lower than those in the intercritical phase (8.5 +- 0.9 mg/dL or 510 mol/L);p <0.0001) 22
  • sUA may behave as negative reactant, being lowered temporarily during episodes of acute inflammation and stress. There may also be an increased renal excretion of uric acid during acute episodes. 22
  • Clinical laboratories often define hyperuricemia as above the normal sUA range based on population norms, which can range up to 480-510 mol/L, where clinically significant hyperuricemia is an sUA > 360 mol/L. 17
  • In physiologic terms, any level above 360 mol/L is hyperuricemia, since it exceeds the soluble concentration of MSU in body fluid. Hyperuricemia should be considered one of the risk factors for gout. Some individuals may develop gout without sUA and some individuals with elevated sUA do not develop gout. 23
  • There is also a strong association between diet and lifestyle factors and sUA levels which may impact sUA measurements. Multiple measurements may be important to determining a patient's true sUA level. 20

Best time to measure sUA: