title: Amino-aciduria and enzymuria in patients with artificial heart valves.
abstract: Fifteen patients with artificial heart valves and evidence of chronic intravascular haemolysis were studied for proximal tubular dysfunction. Three patients had haemosiderinuria and haemoglobinuria; 2 had haemoglobinuria alone. Increased urinary amino acid nitrogen occurred in 8, raised fractional beta 2-microglobulin excretion in 2, hypophosphataemia in 4, renal glycosuria in 1 and enhanced fractional urate excretion in 1. Urinary N-acetyl-beta-glucosaminidase (NAG) excretion increased in 7; the mean urinary NAG/creatinine ratio was raised to twice the upper limit of the normal range. Renal haemosiderosis due to chronic intravascular haemolysis could cause tubular injury.
authors.affiliation: Department of Medicine, Queen Mary Hospital, University of Hong Kong.
authors.forename: P C
authors.initials: PC
authors.lastname: Chan
authors.forename: W H
authors.initials: WH
authors.lastname: Chow
authors.forename: S C
authors.initials: SC
authors.lastname: Tam
authors.forename: I K
authors.initials: IK
authors.lastname: Cheng
authors.forename: M K
authors.initials: MK
authors.lastname: Chan
mesh_terms: D000118:Acetylglucosaminidase / Q000652:urine*; D000328:Adult; D003404:Creatinine / Q000652:urine; D005260:Female; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000652:urine; D000608:Renal Aminoacidurias / Q000209:etiology*; D012214:Rheumatic Heart Disease / Q000601:surgery; D001613:beta 2-Microglobulin / Q000652:urine
chemical_list: D001613:beta 2-Microglobulin; D003404:Creatinine; D000118:Acetylglucosaminidase; D009584:Nitrogen