Mucolipidosis II/III Plasma Screen
|Disease names||Mucolipidosis II/ I-Cell disease
Mucolipidosis IIIA/ Pseudo-Hurler Polydystrophy
|Clinical info||Mucolipidosis II (ML II), also known as I-Cell disease, and Mucolipidosis IIIA (ML IIIA), also known as Pseudo-Hurler Polydystrophy, are lysosomal storage disorders caused by a deficiency of N-acetylglucosamine-1-phosphotransferase (NAPT). ML II is associated with a more severe course including growth failure and failure to thrive, severe developmental delay, coarse facial features, skeletal anomalies and frequent upper respiratory infections. ML II is often lethal in childhood. ML IIIA is associated with a similar, but milder course with a wider spectrum of features and severity. In ML II and ML IIIA, lysosomal hydrolase enzymes are not properly targeted to the lysosome. Therefore, the enzyme activity of multiple lysosomal hydrolases is increased in plasma and other body fluids.|
|Methodology||The activity of 3 lysosomal hydrolases are measured in plasma. The assay uses 4-methylumbelliferyl substrates to measure the activities of hexosaminidase, beta-glucuronidase, and alpha-fucosidase. Prenatal diagnosis and carrier testing via enzyme analysis are not available.|
Mucolipidosis II/III Dried Blood Spot Screen is also available and includes acid sphingomyelinase, alpha-iduronidase, beta-glucosidase, and alpha-mannosidase.
Molecular analysis of the gene for ML II/III (GNPTAB) is also available for identification of the causative mutation within a family, carrier status and prenatal diagnosis.
Enzyme activity can be measured in plasma. Please send 5-10 ml of whole blood in a green top (sodium heparin) tube OR plasma can removed from spun down sample and sent frozen.
Whole blood should be sent overnight at ambient temperature. Plamsa can be removed once the sample has been drawn and sent frozen on dry ice. Do not freeze whole blood.
|Turnaround time||10 days|
|CPT Codes||82657 (X2)|
Whole blood or plasma sample: $400
The Biochemical Lab provides diagnostic and screening tests for a variety of inherited metabolic disorders.