URATE - plasma or serum

---

Specimen: 5 mL blood in lithium heparin or plain tube.

Method: Spectrophotometry.

Reference Interval:

Male:	0.20-0.45 mmol/L
Female:	0.15-0.40 mmol/L

Application: 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.

Interpretation: 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.

Reference: Whelton MD et al. In: Burtis C and Ashwood ER eds. Tietz Textbook of Clinical Chemistry. 2nd ed. WB Saunders 1994.

---