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What is Phenylketonuria is detected by which urine test: and explain in detail?
Guthrie Test: It is a rapid screening test. 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. Good to know: Ferric chloride Test: Phenyl ketones in urine can be detected by this test. A transient blue-green color is a positive test. Nitroprusside Test is used for the colour reaction of amino acid Sulfhydryl group (Cysteine.) Ref: Textbook of Biochemistry DM Vasudevan, 5th Ed Page 22, 206