​For routine Uric Acid testing: 3 mL plain blood

For patients on Rasburicase: 3 mL lithium heparin blood. To pre-chill tube, keep cold on ice and send immediately. Please alert the Clinical Biochemistry Laboratory when sending these specimens.

Enzymatic Colourimetry

0 – < 1 mth : 59 - 271 µmol/L

1 mth – 3 yrs : 65 - 330 µmol/L

4 – 9 yrs : 106 - 325 µmol/L

10 – 15 yrs : 130 - 413 µmol/L

≥ 16 yrs : M 218 - 578; F 178 - 459 µmol/L

​Mean = 4 hrs, Range: 3 – 5 hrs

​Daily

​Uric acid testing for patients on Rasburicase treatment:

Rasburicase is generally used for the treatment of hyperuricaemia in tumour lysis syndrome. It lowers plasma/serum uric acid levels by metabolising Uric Acid to Allantoin and this process continues ex-vivo post blood collection. Delayed analysis of these specimens may therefore lead to falsely low Uric Acid results, giving an incorrect impression of treatment success. In order to reduce ex-vivo degradation of Uric Acid, specimens should be taken in pre-chilled lithium heparin tubes and sent on ice immediately.