Test ID KD2T Krabbe Disease Second-Tier Newborn Screen, Blood Spot
Necessary Information
1. Birth weight (grams)
2. Time of birth (24-hour time)
3. Gestational age (weeks)
Specimen Required
Supplies: Card-Blood Spot Collection (Filter Paper) (T493)
Container/Tube:
Preferred: Blood Spot Collection Card
Acceptable: PerkinElmer 226 filter paper, Munktell filter paper, Whatman Protein Saver 903 paper, local newborn screening card, or blood collected in tubes containing heparin or EDTA and dried on filter paper.
Specimen Volume: 3 Blood spots
Collection Instructions:
1. Completely fill at least 3 circles on the filter paper card (approximated 100-microliters blood per circle).
2. Let blood dry on filter paper at ambient temperature in a horizontal position for a minimum of 3 hours.
3. Do not expose specimen to heat or direct sunlight.
4. Do not stack wet specimens.
5. Keep specimen dry.
Additional Information:
1. For collection instructions, see Blood Spot Collection Instructions.
2. For collection instructions in Spanish, see Blood Spot Collection Card-Spanish Instructions (T777).
3. For collection instructions in Chinese, see Blood Spot Collection Card-Chinese Instructions (T800).
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).
Useful For
Second-tier testing of newborns with an abnormal screening result for Krabbe disease
Follow-up testing after an abnormal newborn screening result for Krabbe disease
Genetics Test Information
This test is used as a second-tier newborn screen for Krabbe disease (galactocerebrosidase deficiency) and includes both psychosine measurement and DNA analysis for the 30-kb deletion.
Highlights
Krabbe disease (globoid cell leukodystrophy) is an autosomal recessive lysosomal storage disorder caused by an enzyme deficiency of galactocerebrosidase (GALC).
Although Krabbe disease is clinically variable, the most common and severe form of the disorder is early infantile onset that presents with rapid neurological regression and results in early death.
Second-tier testing reduces the number of false-positive results reported out.
Elevations in psychosine or the presence of a homozygous 30 kilobase deletion of the GALC gene support a diagnosis of Krabbe disease.
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)/Polymerase Chain Reaction with Gel Electrophoresis
Reporting Name
Krabbe Disease 2ND Tier NBS, BSSpecimen Type
Whole bloodSpecimen Minimum Volume
2 Blood spots
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole blood | Ambient (preferred) | 96 days | FILTER PAPER |
Frozen | 96 days | FILTER PAPER | |
Refrigerated | 96 days | FILTER PAPER |
Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday through Saturday
Report Available
2 to 3 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82542
81401
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
KD2T | Krabbe Disease 2ND Tier NBS, BS | 62309-0 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
48536 | Interpretation | 62309-0 |
48535 | Reviewed By | 18771-6 |
BG704 | Birth Weight (grams, XXXX) | 8339-4 |
BG705 | Time of Birth (24hr Time, XX:XX) | 57715-5 |
BG706 | Gestational Age (weeks, XX.X) | 76516-4 |
NY State Approved
YesSpecial Instructions
Testing Algorithm
If the patient has abnormal newborn screening result for Krabbe disease, immediate action should be taken. Refer to the appropriate ACMG Newborn Screening ACT Sheet.(1)