GALACTOSE-1-PHOSPHATE URIDYLTRANSFERASE (GALT Enzyme), RBC

Specimen Required
Draw blood in a lavender EDTA tube. Send 7.0 mL whole blood (3.0 mL minimum) refrigerated.

Alternate Specimen
Whole blood: Sodium or lithium heparin

Rejection Criteria
Grossly hemolyzed specimens

Methodology
Enzymatic/Liquid Chromatography-Tandem Mass Spectrometry

Stability
Room temperature: Unacceptable; Refrigerated: 5 days; Frozen: Unacceptable

Reference Range
Reference Interval: Greater than or equal to 19.4 U/g Hb
Interpretive Data:
One U/g Hb is equivalent to one umol/hour/gram of hemoglobin (umol/hr/g Hb).
Genotype:   Galactose-1-Phonsphate Uridyltransferase Activity (µmol h-1 gHb-1)  
Classic galactosemia (G/G):   Less than or equal to 0.7  
Duarte galactosemia (D/G):   3.1-7.8  
Classic galactosermia carrier (G/N):   6.5-16.2  
Duarte homozygous (D/D):   6.4-16.5  
Duarte carrier (D/N):   12.0-24.0  
Normal (N/N):   Greater than or equal to 19.4  

Performed
Monday, Wednesday, Friday

Turnaround Time4-7 days
Test CodeGLPHO
CPT-4 Code (s)
82775
LOINC Codes
10970-2

Warde
Medical
Laboratory