Order Code NCLW Neuronal Ceroid Lipofuscinosis, Two-Enzyme Panel, Leukocytes
Ordering Guidance
This blood test is an appropriate first step for individuals between 0 and 4 years of age who present with symptoms consistent with neuronal ceroid lipofuscinosis.
Shipping Instructions
For optimal isolation of leukocytes, it is recommended the specimen arrive refrigerated within 6 days of collection to be stabilized. Collect specimen Monday through Thursday only and not the day before a holiday. Specimen should be collected and packaged as close to shipping time as possible.
Necessary Information
1. Patient's age is required.
2. Reason for testing is required.
Specimen Required
Container/Tube:
Preferred: Yellow top (ACD solution B)
Acceptable: Yellow top (ACD solution A) or lavender top (EDTA)
Specimen Volume: 6 mL
Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.
Forms
1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. Biochemical Genetics Patient Information (T602)
3. If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.
Useful For
Supporting the biochemical diagnosis of two neuronal ceroid lipofuscinoses, CLN1 and CLN2 in whole blood specimens
This test is not useful for carrier detection.
Special Instructions
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
CLN1 and CLN2, WBCSpecimen Type
Whole Blood ACDSpecimen Minimum Volume
5 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Whole Blood ACD | Refrigerated (preferred) | 6 days |
Ambient | 6 days |
Reject Due To
Gross hemolysis | Reject |
Reference Values
Palmitoyl-protein thioesterase 1: >10.0 nmol/h/mg protein
Tripeptidyl peptidase 1: >20.0 nmol/h/mg protein
An interpretative report will be provided.
Method Description
Leukocytes are incubated with four cocktail mixes: 1) substrate and internal standard (IS) for iduronate 2-sulfatase, heparan N-sulfatase, alpha-N-acetylglucosaminidase, N-acetylgalactosamine-sulfate, beta-galactosidase, arylsulfatase B, beta-glucuronidase, and tripeptidyl peptidase 1; 2) substrate and IS for acetyl-CoA:alpha-glucosaminide N-acetyltransferase; 3) substrate and IS for N-acetylglucosamine-6-sulfatase; and 4) substrate and IS for palmitoyl-protein thioesterase 1 in 96-well plates. Following overnight incubation, the plates are combined and purified by liquid-liquid extraction. The extracts are evaporated, reconstituted with mobile phase, and analyzed by tandem mass spectrometry.(Unpublished Mayo method)
Day(s) Performed
Preanalytical processing: Monday through Saturday
Testing performed: Tuesday
Performing Laboratory

CPT Code Information
82657