title: Novel Methods of Determining Urinary Calculi Composition: Petrographic Thin Sectioning of Calculi and Nanoscale Flow Cytometry Urinalysis.
abstract: Accurate determination of urinary stone composition has significant bearing on understanding pathophysiology, choosing treatment modalities and preventing recurrence. A need exists for improved methods to determine stone composition. Urine of 31 patients with known renal calculi was examined with nanoscale flow cytometry and the calculi collected during surgery subsequently underwent petrographic thin sectioning with polarized and fluorescent microscopy. Fluorescently labeled bisphosphonate probes (Alendronate-fluorescein/Alendronate-Cy5) were developed for nanoscale flow cytometry to enumerate nanocrystals that bound the fluorescent probes. Petrographic sections of stones were also imaged by fluorescent and polarized light microscopy with composition analysis correlated to alendronate +ve nanocrystal counts in corresponding urine samples. Urine samples from patients with Ca(2+) and Mg(2+) based calculi exhibited the highest alendronate +ve nanocrystal counts, ranging from 100-1000 nm in diameter. This novel urine based assay was in agreement with composition determined by petrographic thin sections with Alendronate probes. In some cases, high alendronate +ve nanocrystal counts indicated a Ca(2+) or Mg(2+) composition, as confirmed by petrographic analysis, overturning initial spectrophotometric diagnosis of stone composition. The combination of nanoscale flow cytometry and petrographic thin sections offer an alternative means for determining stone composition. Nanoscale flow cytometry of alendronate +ve nanocrystals alone may provide a high-throughput means of evaluating stone burden.
authors.affiliation: Department of Surgery, Division of Urology, Department of Surgery, Western University, London, Ontario, Canada.|Translational Prostate Cancer Research Laboratory, Lawson Health Research Institute, London, Ontario, Canada.
authors.forename: Carson T
authors.initials: CT
authors.lastname: Gavin
authors.affiliation: Department of Surgery, Division of Urology, Department of Surgery, Western University, London, Ontario, Canada.|Translational Prostate Cancer Research Laboratory, Lawson Health Research Institute, London, Ontario, Canada.
authors.forename: Sohrab N
authors.initials: SN
authors.lastname: Ali
authors.affiliation: Department of Surgery, Division of Urology, Department of Surgery, Western University, London, Ontario, Canada.
authors.forename: Thomas
authors.initials: T
authors.lastname: Tailly
authors.affiliation: Department of Surgery, Division of Urology, Department of Surgery, Western University, London, Ontario, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Olvera-Posada
authors.affiliation: Department of Surgery, Division of Urology, Department of Surgery, Western University, London, Ontario, Canada.
authors.forename: Husain
authors.initials: H
authors.lastname: Alenezi
authors.affiliation: Department of Surgery, Division of Urology, Department of Surgery, Western University, London, Ontario, Canada.
authors.forename: Nicholas E
authors.initials: NE
authors.lastname: Power
authors.affiliation: Department of Chemistry, Western University, London, Ontario, Canada.
authors.forename: Jinqiang
authors.initials: J
authors.lastname: Hou
authors.affiliation: Department of Chemistry, Western University, London, Ontario, Canada.
authors.forename: Andre H
authors.initials: AH
authors.lastname: St Amant
authors.affiliation: Department of Chemistry, Western University, London, Ontario, Canada.
authors.forename: Leonard G
authors.initials: LG
authors.lastname: Luyt
authors.affiliation: Department of Earth Sciences, Western University, London, Ontario, Canada.
authors.forename: Stephen
authors.initials: S
authors.lastname: Wood
authors.affiliation: Department of Earth Sciences, Western University, London, Ontario, Canada.
authors.forename: Charles
authors.initials: C
authors.lastname: Wu
authors.affiliation: Department of Surgery, Division of Urology, Department of Surgery, Western University, London, Ontario, Canada.
authors.forename: Hassan
authors.initials: H
authors.lastname: Razvi
authors.affiliation: Department of Surgery, Division of Urology, Department of Surgery, Western University, London, Ontario, Canada.|Translational Prostate Cancer Research Laboratory, Lawson Health Research Institute, London, Ontario, Canada.
authors.forename: Hon S
authors.initials: HS
authors.lastname: Leong
mesh_terms: D005434:Flow Cytometry; D005456:Fluorescent Dyes; D006801:Humans; D007669:Kidney Calculi / Q000175:diagnosis; D008856:Microscopy, Fluorescence; D008867:Microtomy; D016482:Urinalysis / Q000379:methods; D014545:Urinary Calculi / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes