Uridine Diphosphate-Galactose 4' Epimerase, Blood

Casandra

Casandra Test Code MC54734Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID GALECPT Code 82542

Uridine Diphosphate-Galactose 4' Epimerase, Blood

Clinical Use

Use

This test is used for the diagnosis of uridine diphosphate-galactose 4' epimerase deficiency, a rare metabolic disorder classified under the umbrella of galactosemia. The condition is characterized by a deficiency in one of the key enzymes that convert galactose to glucose, culminating in various health problems including liver and kidney dysfunction. The test measures enzyme activity in red blood cells to diagnose the deficiency. For patients with deficiency symptoms, such as those affecting liver, kidney, and the development of cataracts, the test can confirm the diagnosis and guide diet-related treatments to improve symptoms and prevent developmental delays.

Special Instructions

Patient's age is required for test interpretation. For patients in New York, informed consent for genetic testing is required. The Biochemical Genetics Patient Information form (T602) is recommended to aid in result interpretation but is not mandatory. This test is not suitable for monitoring dietary compliance in GALE-deficient patients, nor for detecting GALK, GALT, or GALM deficiencies—alternative tests are recommended for these conditions.

Limitations

This test will not detect galactokinase (GALK) deficiency, galactose-1-phosphate uridyltransferase (GALT) deficiency, or galactose mutarotase (GALM) deficiency. It is not appropriate for monitoring dietary compliance for patients with GALE deficiency; instead, Gal1P levels should be used for monitoring. Additionally, results of enzymatic testing performed in erythrocytes are invalid following transfusion. The test's performance characteristics were determined consistent with CLIA requirements, but it is not cleared or approved by the FDA.

Test Details

New York Approved