CYSTINE IN WHITE BLOOD CELLS
BIOCHEMICAL ANALYSIS

Description:

This protocol allows for the determination of the cystine levels in white blood cell extracts. Cellular cystine is elevated in cystinosis. The measurement of white blood cell cystine is useful in the diagnosis and management of these individuals. White blood cells are isolated as described previously in this manual. In keeping with historical literature, the concentration is expressed as micromoles of half cystine/mg cell protein. The concentration of the cystine is determined by amino acid analysis using the ninhydrin reaction.

Specimen Requirements:

Send 7-10 ml of heparinized blood (green top tube) on wet ice in an insulated container by overnight carrier. Sample must arrive at our location within 48 hrs.

Normal Range:

White Blood Cells: < 0.2 nmoles 1/2 cys/mg protein
Cystinosis: 4.0-13.2 nmol 1/2 cys/mg protein

Turnaround Time:

8 days

CPT Codes and Prices:

82131, 84155

Shipping Information

Forms:

>> Biochemical Requisition

Test Codes:

4627