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Increased galactose occurs when there is a deficiency of one of the three enzymes that metabolize galactose, a sugar derived from milk (see diagram below). The first step in this metabolic pathway converts galactose to galactose-1-phosphate (Gal-1-P). This is mediated by the enzyme galactokinase (GALK). GALK deficiency produces cataracts if untreated. The second step in the pathway exchanges the Gal-1-P for the glucose-1-phosphate (G-1-P) of uridine diphosphate glucose (UDPG) to form uridine diphosphate galactose (UDPGal) and release G-1-P. This step is mediated by the Gal-1-P uridyltransferase (GALT) enzyme, and a deficiency in this enzyme produces galactosemia, the most frequent and most severe disorder of galactose metabolism. Galactosemia is a severe disease in neonates with liver disease, coagulopathy and high risk for neonatal septicemia (generally E.Coli).
The third enzyme in the process, uridine diphosphate galactose ­4-epimerase (GALE) reconverts UDPGal to UDPG. A deficiency of this enzyme is probably benign.

History and Examination
The infant and parent(s) must be seen immediately following notification by telephone from the newborn screening laboratory. A METABOLIC PHYSICIAN MUST BE CONSULTED..

History
The infant may have a normal history. This is especially true if he/she has GALK or GALE deficiency rather than galactosemia (GALT deficiency) or a mild variant of galactosemia. However, a history that includes one, or more, of the following features is consistent with galactosemia: -
Lethargy, poor feeding, jaundice, liver disease, coagulopathy or septicemia

Examination
The infant may appear to be well. However, by two or three days of age, many of these infants will become jaundiced (often severely so), feed poorly, lose weight and be lethargic.
The most striking laboratory finding is positive urine non-glucose reducing substance. Thus, clinitest will be positive, at least 2+, and often 4+, and clinistix or glucostix will be negative or only trace. Liver function testing will reveal markedly increased alkaline phosphatase and at least mildly increased AST & ALT. Notably, a coagulation screen will reveal evidence of an impending coagulopathy with markedly increased PT and PTT.

ANY signs of illness must be considered a medical emergency.

If the child appears well it is still essential to refer to the metabolic center to ensure that the child and family receive the necessary treatment and guidance to prevent any morbidity.
Contact the metabolic physician for markedly elevated GAL

Discussion with parents for markedly elevated GAL

ENSURE THAT THE REPEAT NEWBORN SCREENING SAMPLE IS SENT TO THE STATE LABORATORY AND THE RESULT OBTAINED ASAP

NOTE: It is important to specify what feed (e.g. breast, formula, or soy formula etc..) the infant is taking when sending the repeat specimen.

(Go to NNSGRC for the state labs)

 

Instructions
Results: