Galactosemia is a medical condition resulting from an inability to break down a substance called galactose. Typically found in dairy foods, galactose requires specific enzymes to break it down, and if an enzyme is not present, symptoms of illness arise. Visual symptoms of galactosemia, which typically are seen almost immediately when a newborn drinks breast-milk or other milk, include a swollen stomach, jaundice and slow growth. Blood tests for substances like glucose and amino acids can help diagnose symptoms of galactosemia even before obvious physical issues arise.
As galactosemia is a disease of the metabolic system, the symptoms of galactosemia generally are noted very early on in life. Galactose is an integral component of milks, including breast milks, and formula milks made from cow's milk. Although all cases of galactosemia are as a result of a baby lacking a functional gene for an enzyme that can break down galactose, several different genes are involved.
Absence of the necessary enzymes means that babies who ingest galactose cannot break it down in a normal manner. Instead, the galactose, and molecules made from galactose, collect inside the body and produce damaging effects. Four main areas of the body are most affected, the eyes, the liver, the kidneys and the brain. Liver damage can produce the skin yellowing of jaundice and the medical finding of an enlargement of the liver. Fluid also collects in the stomach, and babies do not put on as much weight as is normal for children of their age.
Blood tests can identify the presence of galactosemia if it is suspected. Low blood glucose is one of the symptoms of galactosemia, as is the presence of amino acids in the bloodstream. Amino acids are the building blocks of proteins, and their presence in blood or in urine is a significant medical finding. Urine ketones, which are molecules that are made when a body breaks down its own tissues, are also a sign of the disease. Hospital laboratories may also be able to analyze the baby's blood for the presence or absence of the enzymes involved.
A lethargic baby, who refuses to feed and who is more irritable than normal, may be at risk of galactosemia. As they age, if the condition is not controlled adequately, the children may suffer from a slower than usual physical development, and may even have intellectual difficulties. Damage to the eye can produce cataracts; as the person is genetically unable to metabolize galactose, these problems can arise if milk products are eaten anytime during the individual's lifetime.