In many states throughout the world, infants routinely undergo newborn screening (NBS) for<unk> . This allows a diagnosis to be made while the person is still an infant. Infants affected by<unk>  typically present with symptoms of lethargy, vomiting, diarrhea, failure to thrive, and jaundice. None of these symptoms are specific to<unk> , often leading to diagnostic delays. If the family of the baby has a history of<unk> , doctors can test prior to birth by taking a sample of fluid from around the fetus (amniocentesis) or from the placenta (chorionic villus sampling or CVS).<unk>  is normally first detected through newborn screening which if available, is able to diagnose the majority of affected infants. A<unk>  test is a blood test (from the heel of the infant) or urine test that checks for three enzymes that are needed to change galactose sugar that is found in milk and milk products into glucose, a sugar that the human body uses for energy. A person with<unk>  doesn't have one of these enzymes. This causes high levels of galactose in the blood or urine. Affected children can have serious, irreversible effects or even die within days from birth. It is important that newborns be screened for metabolic disorders without delay.<unk>  can even be detected through NBS before any ingestion of galactose-containing formula or breast milk. Detection of the disorder through NBS does not depend on protein or lactose ingestion, and, therefore, it should be identified on the first specimen unless the infant has been transfused. A specimen should be taken prior to transfusion. The enzyme is prone to damage if analysis of the sample is delayed or exposed to high temperatures. The routine NBS is accurate for detection of<unk> . Two screening tests are used to screen infants affected with<unk> —the Beutler's test and the Hill test. The Beutler's test screens for<unk>  by detecting the level of enzyme of the infant. Therefore, the ingestion of formula or breast milk does not affect the outcome of this part of the NBS, and the NBS is accurate for detecting<unk>  prior to any ingestion of galactose. Duarte<unk>  is a milder form of classical<unk>  and usually has no long term side effects. Types Galactose is converted into glucose by the action of three enzymes, known as the Leloir pathway. There are diseases associated with deficiencies of each of these three enzymes: Type Diseases Database OMIM Gene Locus Enzyme Name Type 1 9p13 galactose-1-phosphate uridyl transferase classic<unk>  Type 2 17q24 galactokinase galactokinase deficiency Type 3 1p36-p35 UDP galactose epimerase galactose epimerase deficiency, UDP-Galactose-4-epimerase deficiency Normal metabolic pathway for galactose in humans. Galactose metabolism
Galactosemia
Pentosuria
Orotic aciduria
Glycosuria
D-Glyceric acidemia
Isovaleric acidemia
Hawkinsinuria
Sialuria