1 mL blood in a heparin tube preferred. Preferably send on ice to the laboratory immediately as some amino acids are labile.
A brief clinical history is essential.
If free homocystine or cystine is required sample MUST go on ice immediately to lab.
For routine analysis a sample sent immediately at room temperature to the laboratory is acceptable. Samples need to be spun, separated and frozen within an hour of collection.
The reference interval will be provided with the result.
Uncertainty of measurement: 7 - 11%
Test is available urgently if required contact laboratory on x22016 or via LabLink
Water Acquity Amino Acid analyser
Pre-column derivatisation with reverse phase separation
NO CHANGE:
Urine cystine quantitation is used for the diagnosis and monitoring of cystinuria. For cystinosis, see White Cell Cystine. Cystinuria is the result of defective transport of cystine and the dibasic amino acids lysine, arginine and ornithine through the epithelial brush border of the renal tubules and small intestine. Because of low cystine solubility patients present with urolithiasis and its complications. They are otherwise asymptomatic.
PLEASE ALSO ADD:
Stone screening for Cystinuria and other causes is available using the urine metabolic screening test.
For further information contact laboratory: ext 22016 or via Lablink
or, contact the Metabolic Physician-on-call: 09 367 0000
Specimen must arrive on ice for free homocystine or cystine requests.
Other requests preferably on ice, separate 0.2ml plasma and freeze specimen immediately. Accept ambient samples up to 4 hours post collection but please note on form.
Send frozen to LabPlus (-70 o C if possible).