TEST CATALOG ORDERING & RESULTS SPECIMEN HANDLING CUSTOMER SERVICE EDUCATION & INSIGHTS
Test Catalog

Test ID: GALK    
Galactokinase, Blood

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

See Galactosemia Testing Algorithm in Special Instructions for additional information.

Specimen Type Describes the specimen type validated for testing

Whole Blood EDTA

Advisory Information

This test is for diagnosis of galactokinase (GALK) deficiency and does not detect either galactose-1-phosphate uridyltransferase (GALT) deficiency, the most common cause of galactosemia, or uridine diphosphate-galactose 4' epimerase (GALE) deficiency. In most cases, GALT deficiency should be ruled out prior to evaluating for GALK deficiency.

-The preferred test to evaluate for possible diagnosis of galactosemia, routine carrier screening, and followup of abnormal newborn screening results is GCT / Galactosemia Reflex, Blood.

-To evaluate GALT deficiency only, order GALT / Galactose-1-Phosphate Uridyltransferase, Blood

-To evaluate for GALE deficiency only, order GALE / UDP-Galactose 4' Epimerase (GALE), Blood

 

This assay is not appropriate for monitoring dietary compliance. If dietary monitoring is needed, order GAL1P / Galactose-1-Phosphate (Gal-1-P), Erythrocytes.

Necessary Information

Biochemical Genetics Patient Information (T602) is recommended, but not required, to be filled out and sent with the specimen to aid in the interpretation of test results.

Specimen Required Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Multiple whole blood tests for galactosemia can be performed on 1 specimen. Prioritize order of testing when submitting specimens. See Galactosemia-Related Test List in Special Instructions for a list of tests that can be ordered together.

 

Container/Tube:

Preferred: Lavender top (EDTA)

Acceptable: Green top (sodium or lithium heparin) or yellow top (ACD)

Specimen Volume: 4 mL

Special Instructions Library of PDFs including pertinent information and forms related to the test

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 in Special Instructions:

-Informed Consent for Genetic Testing (T576)

-Informed Consent for Genetic Testing-Spanish (T826)

2. Biochemical Genetics Patient Information (T602) is recommended, see Special Instructions.

3. If not ordering electronically, complete, print, and send an Inborn Errors of Metabolism Test Request (T798) with the specimen.

Specimen Minimum Volume Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

2 mL

Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject

Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen TypeTemperatureTimeSpecial Container
Whole Blood EDTARefrigerated (preferred)10 days
 Ambient 72 hours