To distinguish patients who have classic galactosemia (at high clinical risk) from those who are compound heterozygotes for a galactosemia mutation and the Duarte variant (at low clinical risk) requires an additional complex GALT isoelectric-focusing procedure to demonstrate the electrophoretic mobility of the variant proteins.
In this issue of Clinical Chemistry, 2 reports push the boundaries of analytical sensitivity and versatility for galactosemia diagnosis with ultra-performance liquid chromatography--tandem mass spectrometry (UPLC-MS/MS) (12, 13).
This study did not focus on the ability of the GALT assay to distinguish variant forms of galactosemia, but rather on the ability to multiplex all 3 enzyme assays in a single test.
With relatively simple enzymological procedures and on-column analytical run times of <30 min per sample with unlimited batch size, these studies taken together have clearly redefined the gold standard for laboratory confirmation of galactosemia diagnosis.
La hiperplasia adrenal congenita y la galactosemia fueron incluidas en enero de 2002 despues de un programa piloto (1999-2000).
Also to this date, 259 children with congenital hypothyroidism, 18 with phenylketonuria, 20 with the maple syrup disease, 30 with congenital adrenal hyperplasia and 10 with galactosemia have been detected, confirmed and treated, for a total of 337 children that were spared of mental retardation, other disabilities and even death.
The diagnostic confirmation of the IMDs PKU, MSD and galactosemia, ate carried out in the High Risk Section of the Central Screening Laboratory.
It is surprising to observe an apparent high frequency of galactosemia 1:9907 in our newborn population.
Newborn (NB)  screening for galactosemia is done primarily to detect clinically devastating galactosemia due to defective function of galactose-1-phosphate uridyltransferase (GALT) (1).
To assess the specificity of galactosemia screening, we compiled NB-screening data in our laboratory from January 1,2001, to March 1,2006, for >1.3 x [10.sup.6] NBs.
A GALT value [less than or equal to] 32 [micro]mol/L is typical in GALT-deficient galactosemia, whereas GALT activity values of 41-120 [micro]mol/L are common with clinically benign mutations.
Before September 2006, the PA DOH defined a positive result for non-GALT-deficient galactosemia as a Gal concentration [greater than or equal to] 1.110 mmol/L ([greater than or equal to] 20 mg/dL).