Preferred Sample Type
Suitable Specimen Types
- Li Hep Plasma
Specimen Transport
Send sample frozen to referral laboratory.
Sample Processing in Laboratory
Usual
Sample Preparation
Centrifuge sample and store frozen.
Turnaround Time
2 weeksSample Stability
-20 ºC
I Cell Screen
General Information
The I-cell screen measures the activity of the enzyme Arylsulphatase A, which is greatly increased in Mucolipidoses type II (I-cell disease) and type III (pseudo-Hurler polydystrophy). These disorders are both caused by a deficiency of an enzmye called N-acetylglucosamine-1-phosphotransferase. This enzyme phophorylates mannose residues on the carboyhydrate chain of lysosomal enzymes allowing their uptake into the lysosome. The failure to phosphorylate the mannose residues in these diseases leads to the secretion of these enzymes into the intercellular fluid and blood. As a consequence the activity of a wide range of lysosomal enzymes is deficient in some tissues whilst their concentration in plasma is grossly elevated.
Patient Preparation
None
Notes
Grossly haemolysed specimens may make interpretation difficult.
Reference Range
Provided by reference laboratory.