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What is Ferric chloride test in PKU gives and explain in detail?
Urine of the patient contains phenylketones about 500- 3000 mg/day . This could be detected by adding a drop of ferric chloride to the urine . A transient blue - green color is a positive test. But this is a less reliable test. Ref : DM.VASUDEVAN.TEXTBOOK ; SEVENTH EDITION ; PAGE NO : 237.