Hyperuricemia is a classic feature of gout. Gout occurs nearly half of the time without hyperuricemia and most people with raised uric acid levels never develop gout. The usefulness of measuring uric acid levels is limited. Hyperuricemia is defined as a plasma urate level greater than 420 "μ"mol/L (7.0 mg/dL) in males and 360 "μ"mol/L (6.0 mg/dL) in females. Other blood tests commonly performed are white blood cell count, electrolytes, renal function, and erythrocyte sedimentation rate(ESR). Both the white blood cells and ESR may be elevated due to gout in the absence of infection. A white blood cell count as high as 40.0×10/L (40,000/mm) has been documented in people with gout.