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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)
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