title: How variations in the composition of urine influence urease-induced crystallization.
abstract: To Study how the composition of urine influences urease-induced crystallization, human urine samples were incubated with urease and the subsequent precipitation measured. Beside the pH increase, the urinary content of magnesium and calcium had profound effects on the precipitation of magnesium ammonium phosphate and calcium phosphate, respectively. Urine phosphate, ammonium and osmolarity had no direct effects on the precipitation. Among the urine components with potential inhibitory properties, only albumin was found to be correlated with such an effect. This inhibitory activity was especially influential in urines with high calcium and magnesium levels. These findings suggest that the composition of urine could also influence the formation of stones consisting of magnesium ammonium phosphate and calcium phosphate.
authors.affiliation: Department of Urology, Sahlgren's Hospital, Göteborg, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Hugosson
authors.forename: L
authors.initials: L
authors.lastname: Grenabo
authors.forename: H
authors.initials: H
authors.lastname: Hedelin
authors.forename: S
authors.initials: S
authors.lastname: Pettersson
authors.forename: I
authors.initials: I
authors.lastname: Tarfusser
mesh_terms: D002129:Calcium Oxalate / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D002130:Calcium Phosphates / Q000652:urine; D003460:Crystallization; D006023:Glycoproteins / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000652:urine; D017616:Magnesium Compounds; D010710:Phosphates / Q000652:urine; D000069877:Struvite; D014510:Urease / Q000494:pharmacology*; D014545:Urinary Calculi / Q000737:chemistry / Q000652:urine; D014556:Urine / Q000737:chemistry*
chemical_list: D002130:Calcium Phosphates; D006023:Glycoproteins; D017616:Magnesium Compounds; D010710:Phosphates; C485828:alpha-tricalcium phosphate; C029490:nephrocalcin; C485830:tetracalcium phosphate; D002129:Calcium Oxalate; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; D000069877:Struvite; D014510:Urease; D008274:Magnesium; C485829:calcium phosphate, dibasic, anhydrous