The Leeds Teaching Hospitals NHS Trust

White cell cystine

White cell cystine

Used in the monitoring and diagnosis of cystinosis. Heterozygotes are phenotypically normal. Homozygotes usually present around 1-2 years old with polyuria, polydypsia, failure to thrive, rickets and Fanconi syndrome (generalised aminoaciduria with phoshaturia and glycosuria). They are treated with Cystagon which reduces lysosomal cystine accumulation and thereby preserves renal function.

Tube Heparin (no gel preferred)
ID 30001
Availability Weekdays
Additional Information Please note Cystinosis is NOT the same disease as cystinuria (a cause of renal stones).
Turn Around 28 days
Send to Specialist Laboratory Medicine
Block 46
St James hospital
Beckett Street
Collection Con Minimum volume: 3 mL

Instructions for lab: Do not separate. Store whole blood at room temperature. Must arrive at Block 46 SJUH within 24 hours of venepuncture to allow white cell preparation (takes 2.5 hours, not available at weekends).

Please discuss with Biochemical Genetics lab prior to rejecting any samples.
Frequency Monthly
Sample REQ Whole blood. Sample must be well mixed at venepuncture to prevent clots and received within 24 hrs of collection between Mon 9am to Fri 2pm. For monitoring a trough sample should be taken.
Ref. Range Notes Normal: up to 0.5.
Heterozygotes: up to 1.0.
Cystinosis patients: usually greater than 2.0.

Units nmol ½ cystine per mg protein
Telepath White cell cystine: CYSW1J
ICE Codes White cell cystine: JCYSW