Amino acids secreted in cystinuria are all except:
Ans:B.)Histidine.CystinuriaBiochemical Defect :An autosomal recessive disorder that results in the formation of a defective amino acid transpoer in the renal tubule and intestinal epithelial cells.Pathophysiology :The amino acid transpoer is responsible for transpoing cysteine, ornithine, lysine, and arginine . Defective tubular reabsorption of these amino acids in the kidneys results in increased cysteine in the urine , which can precipitate and cause kidney stones.Clinical Manifestations : Cysteine kidney stones presenting with severe, intermittent flank pain and hematuria.Lab findings: Increased urinary excretion of cysteine, ornithine, arginine, and lysine on urine amino acid chromatography; hematuria and cysteine crystals (hexagonal) on cooling of acidified urine sediment.Imaging: Radiopaque kidney stones on CT scan.Treatment : Low-methionine diet; increased fluid intake; acetazolamide to alkalinize the urine.
Ornithine
Histidine
Arginine
Lysine