Test that determines whether the urine of a newborn contains phenylketones is called?

• A. PKU test
• B. Potassium test
• C. PSA
• D. Prothrombin Time

Answer: (A)

This item tests your understanding of newborn metabolic screening for phenylketonuria. In PKU, a defect in converting phenylalanine leads to accumulation of phenylketones, such as phenylpyruvic acid, which can be excreted in urine. The test specifically looked for these phenylketones in a newborn’s urine, hence it’s called the PKU test. Early detection is crucial because, if untreated, PKU can cause intellectual disability and developmental problems, but dietary management can prevent these outcomes. The other options measure different things: potassium tests electrolytes in blood, PSA screens for prostate issues, and prothrombin time assesses blood clotting.