Urate

5 mL blood in lithium heparin or plain tube.

Spectrophotometry.

Female: 0.15-0.40 mmol/L

Male: 0.20-0.45 mmol/L.

Diagnosis and monitoring of gout and pregnancy-induced hypertension.

Monitoring of therapy in malignancies where there is a high rate of cell destruction and uric acid production.

Assists in the diagnosis of SIADH.

The likelihood of gout is low if the serum urate concentration is repeatedly below 0.42 mmol/L. The risk of developing gout is three times greater if the serum urate concentration is consistently above 0.42 mmol/L. However, a raised serum urate level alone is insufficient to diagnose gout.

Impaired renal function, pregnancy-induced hypertension, diuretics, fasting, hyperlactataemia, hyperketonaemia and low dose salicylates can all produce increased urate levels.

Hypouricaemia is seen in patients with a low purine intake, in SIADH, with hypouricaemic drugs (eg, allopurinol) and in the rare condition of xanthinuria.