Journal Mobile Options
Table of Contents
Vol. 79, No. 3, 2007
Issue release date: October 2007
Urol Int 2007;79:267–272

Stabilization of Calcium Oxalate Suspension by Urinary Macromolecules, Probably an Efficient Protection from Stone Formation

Baumann J.M. · Affolter B. · Caprez U. · Clivaz C. · Glück Z. · Weber R.
aStone Research Center Viollier, Biel, bBerne University of Applied Sciences, Division of Chemistry, Burgdorf, and cDepartment of Nephrology, Hospital Center Biel, Biel, Switzerland

Individual Users: Register with Karger Login Information

Please create your User ID & Password

Contact Information

I have read the Karger Terms and Conditions and agree.

To view the fulltext, please log in

To view the pdf, please log in


Introduction: Crystal aggregation (AGN) destabilizes crystal suspensions and during crystalluria probably favors crystal apposition to kidney calcifications and preexisting stones. We analyzed inhibition of AGN and stabilization of calcium oxalate suspensions by urinary macromolecules (UM), urine and solutions with urinary citrate concentration. Materials and Methods: Solutions of UM (UMS) were obtained by a hemofiltration procedure from urine of 6 healthy men. Calcium oxalate suspensions were prepared in all solutions and urine by adjusting Ca2+ to 1.5 mM and by an oxalate titration to 1.0 mM. Crystallization was monitored measuring optical density (OD). Stability of suspensions (SS) was defined as the time without sedimentation and zeta potential (ZP) of crystals was measured. AGN was visualized by scanning electron microscopy and quantified by maximal OD. Results: UMS inhibited AGN and increased ZP and SS. Most inhibitory activity of urine could be attributed to UM. 3.3-fold dilution of UM reduced SS only by 30%. Conclusions: During crystalluria, UM of healthy men are supposed to protect from stone formation by inhibiting AGN and stabilizing crystal suspensions. As a probably important aspect, this protection was found to be limited in time and may favorably be influenced by an increase of diuresis.

Copyright / Drug Dosage

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.


  1. Baumann JM, Affolter B, Caprez U, Henze U: Calcium oxalate aggregation in whole urine, new aspects of calcium stone formation and metaphylaxis. Eur Urol 2003;43:421–425.
  2. Müller RH: Zetapontential und Partikelladung in der Laborpraxis. Stuttgart, Wissenschaftliche Verlagsgesellschaft, 1996, vol 37.
  3. Butt AJ: Role of protective urinary colloid in prevention of renal lithiasis. J Urol 1952;67:450–459.
  4. Khan SR, Kok DJ: Modulators of urinary stone formation. Front Biosci 2004;9:1450–1482.
  5. Christmas KG, Gower LB, Khan SR, El-Shall H: Aggregation and dispersion characteristics of calcium oxalate monohydrate: effect of urinary species. J Colloid Interface Sci 2002;256:168–174.
  6. Cao LC, Deng G, Boevè ER, de Bruijn WC, de Water R, Verkoelen CF, Romijn JC, Schroeder FH: Zeta potential measurement and particle size analysis for a better understanding of urinary inhibitors of calcium oxalate crystallization. Scanning Microsc 1996;10:401–414.
  7. Boevè ER, Cao LC, De Bruijn WC, Robertson WG, Romijn JC, Schröder FH: Zeta potential distribution on calcium oxalate crystal and Tamm-Horsfall protein surface analyzed with Doppler electrophoretic light scattering. J Urol 1994;152:531–536.
  8. Hess B, Nakagawa Y, Coe FL: Inhibition of calcium oxalate monohydrate crystal aggregation by urine proteins. Am J Physiol 1989;257:F99–F106.
  9. Scurr DS, Robertson WG: Modifiers of calcium oxalate crystallization found in urine. II. Studies on their mode of action in an artificial urine. J Urol 1986;136:128–131.
  10. Scurr DS, Robertson WG: Modifiers of calcium oxalate crystallization found in urine. III. Studies on the role of Tamm-Horsfall mucoprotein and of ionic strength. J Urol 1986;136:505–507.
  11. Robertson WG: Kidney models of calcium oxalate stone formation. Nephron Physiol 2004;98:21–30.

    External Resources

  12. Finlayson B, Reid F: The expectation of free and fixed particles in urinary stone disease. Invest Urol 1978;15:442–448.
  13. Baumann JM, Affolter B, Caprez U, Henze U, Lauper D, Maier F: Hydroxyapatite induction and secondary aggregation of calcium oxalate, two important processes in calcium stone formation. Urol Res 2001;29:417–422.
  14. Hess B, Zipperle L, Jaeger P: Citrate and calcium effects on Tamm-Horsfall glycoprotein as a modifier of calcium oxalate crystal aggregation. Am J Physiol 1993;265:R784–R791.
  15. Wesson JA, Ganne V, Beshensky AM, Kleinmann JG: Regulation by macromolecules of calcium oxalate crystal aggregation in stone formers. Urol Res 2005;33:206–212.
  16. Asplin JR, Parks JH, Chen MS, Lieske JC, Toback FG, Pillay SN, Nakagawa Y, Coe FL: Reduced crystallization inhibition by urine from men with nephrolithiasis. Kidney Int 1999;56:1505–1516.
  17. Tiselius HG, Fornader AM, Nilsson MA: Effects of urinary macromolecules on the crystallization of calcium oxalate. Urol Res 1990;18:381–385.
  18. Tiselius HG, Fornander AM, Nilsson MA: The effects of citrate and urine on calcium oxalate crystal aggregation. Urol Res 1993;21:363–366.
  19. Khan SR, Finlayson B, Hackett RL: Stone matrix as protein adsorbed on crystal surfaces: a microscopic study. Scan Electron Microsc 1983;1:379–384.
  20. Scurr DS, Robertson WG: Modifiers of calcium oxalate crystallization found in urine. Studies with a continuous crystallizer using an artificial urine. J Urol 1986;135:1322–1326.
  21. Guerra A, Allegri F, Meschi T, Adorni G, Prati B, Nouvenne A, Novarini A, Maggiore U, Fiaccadori E, Borghi L: Effects of urine dilution on quantity, size and aggregation of calcium oxalate crystals induced in vitro by an oxalate load. Clin Chem Lab Med 2005;43:585–589.

Pay-per-View Options
Direct payment This item at the regular price: USD 38.00
Payment from account With a Karger Pay-per-View account (down payment USD 150) you profit from a special rate for this and other single items.
This item at the discounted price: USD 26.50