Guthrie test can be used for the diagnosis of ___________
Phenylketonuria can be detected in 100% of cases by various methods of newborn screening such as Guthrie card bacterial inhibition essay(BIA).This test was developed by Robe Guthrie.Ceain strains of Bacillus subtilis need phenylalanine as an essential growth factor.Bacteria cannot grow in a medium devoid of phenylalanine.Bacterial growth is propoional to the phenylalanine content in the patient&;s blood.Heel-prick blood sample is added to the Guthrie card for this test. It was a "bacterial inhibition assay." A spot of blood on a filter paper disc is placed on the surface of an agar plate containing a substance that inhibits the growth of bacteria. However, the inhibition can be overcome by high phe. After incubating the agar plate overnight, the diameter of the growth zone around the test disc is compared to that of a control disc of blood serum to which a known quantity of phe has been added. This permits one to estimate the amount of phe in the test disc. Reference:Essential pediatrics-Ghai,8th edition,page no:652;Textbook of Biochemistry--DM Vasudevan,6th edition,page no:208.
Tyrosinemia
Galactosemia
Alkaptonuria
Phenyleketonuria
Metabolic disorders