title: A study of struvite precipitation and urease activity in bacteria isolated from patients with urinary infections and their possible involvement in the formation of renal calculi.
abstract: Struvite precipitation and urease activity were studied in 72 bacterial strains isolated from patients with an urinary infection. The results revealed struvite precipitation by urease-positive, urease-negative and weakly urealitic bacteria. However, in some strains of each of these groups, no precipitation was observed. Variations in pH within the cultures were also investigated as were the mineralogy and morphology of the crystals precipitated using X-ray diffraction and scanning electron microscopy, respectively. The role of urease activity and alkalinization of the medium in struvite precipitation is discussed, as is the possible involvement of bacteria in nucleation processes. We concluded that urease-negative bacteria or those with weak urease activity may also be involved in the formation of struvite renal calculi although urease-positive bacteria seem to make a greater contribution.
authors.affiliation: Department of Microbiology, Faculty of Pharmacy, University of Granada, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Rivadeneyra
authors.forename: A
authors.initials: A
authors.lastname: Gutierrez-Calderón
authors.forename: A M
authors.initials: AM
authors.lastname: Rivadeneyra
authors.forename: A
authors.initials: A
authors.lastname: Ramos-Cormenzana
mesh_terms: D011232:Chemical Precipitation; D003460:Crystallization; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007669:Kidney Calculi / Q000209:etiology*; D017616:Magnesium Compounds / Q000378:metabolism*; D008855:Microscopy, Electron, Scanning; D010710:Phosphates / Q000378:metabolism*; D000069877:Struvite; D014510:Urease / Q000378:metabolism*; D014552:Urinary Tract Infections / Q000382:microbiology* / Q000652:urine
chemical_list: D017616:Magnesium Compounds; D010710:Phosphates; D000069877:Struvite; D014510:Urease