Which amino acid becomes conditionally essential in AKI and is listed among commonly conditionally essential amino acids?

• A. Leucine
• B. Tyrosine
• C. Methionine
• D. Lysine

Answer: (B)

In acute kidney injury, the body's metabolism shifts to a stressed, catabolic state, and some amino acids that are normally made by the body must be supplied from the diet. Tyrosine becomes conditionally essential because it is normally produced from phenylalanine by phenylalanine hydroxylase in the liver, but during illness and organ dysfunction this conversion and the overall demand for tyrosine-derived compounds (like catecholamines and thyroid hormones) can outpace the body's ability to meet needs. As a result, dietary tyrosine becomes necessary, which is why tyrosine is listed among commonly conditionally essential amino acids in illness states such as AKI. Leucine, methionine, and lysine are essential under all conditions; they don’t typically shift to conditional essentiality specifically due to AKI.