Jump to ContentJump to Main Navigation
Show Summary Details
More options …

Clinical Chemistry and Laboratory Medicine (CCLM)

Published in Association with the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)

Editor-in-Chief: Plebani, Mario

Ed. by Gillery, Philippe / Lackner, Karl J. / Lippi, Giuseppe / Melichar, Bohuslav / Payne, Deborah A. / Schlattmann, Peter / Tate, Jillian R.

12 Issues per year

IMPACT FACTOR 2016: 3.432

CiteScore 2016: 2.21

SCImago Journal Rank (SJR) 2016: 1.000
Source Normalized Impact per Paper (SNIP) 2016: 1.112

See all formats and pricing
More options …
Volume 43, Issue 6 (Jun 2005)


Effects of urine dilution on quantity, size and aggregation of calcium oxalate crystals induced in vitro by an oxalate load

Angela Guerra
  • Department of Clinical Sciences, University of Parma, Parma, Italy
/ Franca Allegri
  • Department of Clinical Sciences, University of Parma, Parma, Italy
/ Tiziana Meschi
  • Department of Clinical Sciences, University of Parma, Parma, Italy
/ Giuditta Adorni
  • Department of Clinical Sciences, University of Parma, Parma, Italy
/ Beatrice Prati
  • Department of Clinical Sciences, University of Parma, Parma, Italy
/ Antonio Nouvenne
  • Department of Clinical Sciences, University of Parma, Parma, Italy
/ Almerico Novarini
  • Department of Clinical Sciences, University of Parma, Parma, Italy
/ Umberto Maggiore
  • Department of Clinical Medicine, Nephrology and Prevention Sciences, University of Parma, Parma, Italy
/ Enrico Fiaccadori
  • Department of Clinical Medicine, Nephrology and Prevention Sciences, University of Parma, Parma, Italy
/ Loris Borghi
  • Department of Clinical Sciences, University of Parma, Parma, Italy
Published Online: 2005-07-05 | DOI: https://doi.org/10.1515/CCLM.2005.102


Increasing urinary volume is an important tool in the prevention of calcium renal stones. However, the mechanism of how it actually works is only partially understood. This study aimed at assessing how urine dilution affects urinary calcium oxalate crystallization. A total of 16 male idiopathic calcium oxalate (CaOx) stone-formers and 12 normal male subjects were studied and 4 h urine samples were taken twice, under low (undiluted urine) and high hydration conditions (diluted urine). An equal oxalate load (1.3mmol/L) was added to both types of urine and the crystallization parameters were assessed. In both stone-formers and normal subjects, the crystallization processes were significantly (p<0.05 or less) more marked in the undiluted urine than in the diluted urine in terms of: a) total quantity of calcium oxalate dihydrate (COD) and calcium oxalate monohydrate (COM) crystals; b) total quantity of crystalline aggregates; and c) aggregation index (i.e., ratio between the area occupied by crystalline aggregates and the area occupied by all the crystals present). The comparison between stone-formers and normal subjects showed that the greatest difference was for the size of COD crystals, which were larger in the urine of the stone-formers. A further important finding was an inverse relationship between changes in urinary volume and in the aggregation index (r=–0.53, p=0.004). In conclusion, urine dilution considerably reduces crystallization phenomena induced in vitro by an oxalate load in both calcium stone-formers and normal subjects.

Keywords: calcium nephrolithiasis; calcium oxalate crystallization; oxalate load; urinary volume; water load.


  • 1

    Pak CY, Sakhaee K, Crowther C, Brinkley L. Evidence justifying a high fluid intake in treatment of nephrolithiasis. Ann Intern Med 1980; 93: 36–9. CrossrefGoogle Scholar

  • 2

    Borghi L, Meschi T, Amato F, Briganti A, Novarini A, Giannini A. Urinary volume, water and recurrences in idiopathic calcium nephrolithiasis: a 5-year randomized prospective study. J Urol 1996; 155: 839–43. Google Scholar

  • 3

    Borghi L, Meschi T, Schianchi T, Briganti A, Guerra A, Allegri F, et al. Urine volume: stone risk factor and preventive measure. Nephron 1999; 81(Suppl 1): 31–7. Google Scholar

  • 4

    Borghi L, Guerra A, Meschi T, Briganti A, Schianchi T, Allegri F, et al. Relationship between supersaturation and calcium oxalate crystallization in normals and idiopathic calcium oxalate stone formers. Kidney Int 1999; 55: 1041–50. CrossrefGoogle Scholar

  • 5

    Guerra A, Meschi T, Allegri F, Schianchi T, Adorni G, Novarini A, et al. Calcium oxalate crystallization in untreated urine, centrifuged and filtered urine and ultrafiltered urine. Clin Chem Lab Med 2004; 42: 45–50. CrossrefGoogle Scholar

  • 6

    Baumann JM, Affolter B, Brenneisen J, Siegrist HP. Measurement of metastability, growth and aggregation of calcium oxalate in native urine. Urol Int 1997; 59: 214–20. CrossrefGoogle Scholar

  • 7

    Hess B, Kok DJ. Nucleation, growth, and aggregation of stone-forming crystals. In: Coe FL, Favus MJ, Pak CY, Parks JH, Preminger GM, editors. Kidney stones: medical and surgical management. Philadelphia: Lippincott-Raven, 1996:3–32. Google Scholar

  • 8

    Hallson PC, Rose GA. Uromucoids and urinary stone formation. Lancet 1979; 12: 1000–2. CrossrefGoogle Scholar

  • 9

    Kok DJ, Papapoulos SE, Bijvoet OL. Excessive crystal agglomeration with low citrate excretion in recurrent stone-formers. Lancet 1986; 10: 1056–8. CrossrefGoogle Scholar

  • 10

    Edyvane KA, Hibberd CM, Harnett RM, Marshall VR, Ryall RL. Macromolecules inhibit calcium oxalate crystal growth and aggregation in whole human urine. Clin Chim Acta 1987; 167: 329–38. Google Scholar

  • 11

    Hess B, Nakagawa Y, Coe FL. Inhibition of calcium oxalate monohydrate crystal aggregation by urine proteins. Am J Physiol 1989; 257: F99–F106. Google Scholar

  • 12

    Ebisuno S, Kohjimoto Y, Yoshida T, Ohkawa T. Effect of urinary macromolecules on aggregation of calcium oxalate in recurrent calcium stone formers and healthy. Urol Res 1993; 21: 265–8. CrossrefGoogle Scholar

  • 13

    Hess B. Tamm-Horsfall glycoprotein and calcium nephrolithiasis. Mineral Electrolyte Metab 1994; 20: 393–8. Google Scholar

  • 14

    Khan SR. Interactions between stone-forming calcific crystals and macromolecules. Urol Int 1997; 59: 59–71. CrossrefGoogle Scholar

  • 15

    Hess B. Tamm-Horsfall glycoprotein – inhibitor or promoter of calcium oxalate monohydrate crystallization processes? Urol Res 1992; 20: 83–6. CrossrefGoogle Scholar

  • 16

    Ackermann D, Brown P, Khan SR. Preparation and application of calcium oxalate dihydrate crystal seeds. Urol Res 1989; 17: 147–8. Google Scholar

  • 17

    Yuzawa M, Tozuka K, Tokue A. Effect of citrate and pyrophosphate on the stability of calcium oxalate dihydrate. Urol Res 1998; 26: 83–8. CrossrefGoogle Scholar

  • 18

    Berg W, Hesse A, Schneider HJ. A contribution to the formation mechanism of calcium oxalate urinary calculi. III. On the role of magnesium in the formation of oxalate calculi. Urol Res 1976; 4: 161–7. CrossrefGoogle Scholar

  • 19

    Worcester EM. Urinary calcium oxalate crystal growth inhibitors. J Am Soc Nephrol 1994; 5(Suppl 1): 46–53. Google Scholar

  • 20

    Robertson WG, Peacock M. Calcium oxalate crystalluria and inhibitors of crystallization in recurrent renal stone-formers. Clin Sci 1972; 43: 499–506. CrossrefGoogle Scholar

About the article

Corresponding author: Loris Borghi MD, Dipartimento di Scienze Cliniche, Università di Parma, Via Gramsci 14, 43100 Parma, Italy Phone: +39-0521-702007, Fax: +39-0521-940993,

Received: 2005-01-24

Accepted: 2005-03-30

Published Online: 2005-07-05

Published in Print: 2005-06-01

Citation Information: Clinical Chemistry and Laboratory Medicine (CCLM), ISSN (Online) 1437-4331, ISSN (Print) 1434-6621, DOI: https://doi.org/10.1515/CCLM.2005.102.

Export Citation

© Walter de Gruyter Berlin New York. Copyright Clearance Center

Comments (0)

Please log in or register to comment.
Log in