Question

In Cystinuria all of the following aminoacids reabsorption defect is present, except

• A. Lysine
• B. Citrulline
• C. Arginine
• D. Ornithine

Answer 1

The Correct Option is B

Cystinuria is a genetic disorder characterized by defective reabsorption of certain amino acids in the kidneys. This defect affects the transport of dibasic amino acids in the proximal tubule of the kidney.

• Lysine, Arginine, and Ornithine: These are all dibasic amino acids whose reabsorption is impaired in cystinuria. The defective transport leads to increased excretion of these amino acids in the urine.
• Citrulline: Although it is an amino acid, it is not a dibasic amino acid. Citrulline's reabsorption is not affected by cystinuria, and it is primarily involved in the urea cycle rather than being reabsorbed in the kidneys alongside lysine, arginine, and ornithine.

Hence, the correct answer is Citrulline, as its reabsorption defect is not present in cystinuria.