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SUMMARY: ROYAL CANIN Veterinary DietTM/MC feline URINARY SO 30TM/MC (dry) and URINARY SOTM/MC IN GEL (canned) are complete and balanced diets for adult cats that have been formulated to aid in the management of feline lower urinary tract disease (LUTD).

INDICATIONS:

CONTRAINDICATIONS:

For cats with or at risk of developing feline lower urinary tract disease
 -- Growing kittens
  Dry format: -- Pregnant or lactating queens
  --

Dissolve pure struvite urolith

 -- Concurrent use of urinary acidifiers
  -- Helps prevent the formation of struvite uroliths    
    Helps minimize the risk of formation of calcium oxalate    
   

Helps minimize the risk of formation of brushite uroliths

    
   Canned format:    
 
--
 Dissolve pure struvite uroliths    
 
--
 Helps prevent the formation of struvite uroliths    
 
--
 Helps minimize the risk of formation of calcium oxalate uroliths    
 
--
 Helps minimize the risk of formation of brushite uroliths    
 
--
 Aids in the management of idiopathic cystitis, which may present with the following signs:    
 
--Hematuria, dysuria, stranguria, pollakiuria    
 
--Inappropriate urination    


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RATIONALE:
Ten years ago, the majority of uroliths removed from cats were struvite (magnesium ammonium phosphate). Since struvite formation is highly dependent on urine pH, diets designed for managing struvite uroliths encouraged the production of severely acidic urine and were highly restricted in magnesium.

In the past ten years, there has been an increase in the incidence of calcium oxalate urolithiasis. The dietary management tools for struvite (acidification and severe magnesium restriction) have been suggested to be risk factors for calcium oxalate urolith formation.

The management of calcium oxalate urolithiasis is far more challenging than struvite urolithiasis. In humans, calcium oxalate uroliths can form in urine across the full range of normal pH values (4.8-7.4). Urine pH manipulation cannot be used to reliably manage calcium oxalate urolithiasis, nor is the restriction of dietary calcium and oxalate effective in preventing oxalate urolith formation.

Diets specifically designed to prevent one type of urolith may greatly increase the risk of the other type of urolith forming. Waltham Science has taken a safer approach and invested years of research in developing a single diet which effectively reduces the risks for both types of uroliths simultaneously.

URINARY SO 30TM/MC (dry) and URINARY SO IN GELTM/MC (canned) are the first and only diets which have been clinically proven to reduce the risk of both struvite and calcium oxalate urolithiasis.

Urine Evaluation Using RSS:
The desire to develop diets which effectively manage both struvite and calcium oxalate urolithiasis in pets led Waltham to explore complex research methods for predicting urolithiasis risk in dogs and cats.

The predominant urolith in humans is calcium oxalate and more than 30 years ago, human urologists began looking at ways of predicting the risk of calcium oxalate formation in human patients.

The result was the development of a research methodology known as RSS or Relative SuperSaturation. This methodology involves the analysis of 12 constituents of a collected urine sample, as well as the determination of its pH. These data are then analyzed using a computer program that calculates the concentrations of the large number of possible interactive complexes between all ions present in this urine.

Finally, the program calculates the activity product of the urine sample for a given urolith and divides this number by the known constant thermodynamic solubility product for that urolith to determine RSS. If the sample’s activity product is less than the constant, then RSS < 1.0 and the urine is said to be "undersaturated" for that urolith.

Using RSS to assess the risk of struvite urolith formation in cats:

If a diet has an RSS for STRUVITE of:
The urine produced by cats fed that diet is said to be:
And the risk for STRUVITE urolith formation is:
Less than 1
Undersaturated
  • New struvite uroliths will not form
  • Existing struvite uroliths will dissolve
Between 1 and 2.5
Metastable
  • New struvite uroliths will not form
  • Any existing struvite uroliths will not dissolve and may grow
Over 2.5
Oversaturated
  • New struvite uroliths may form
  • Any existing struvite uroliths will grow

 

Using RSS to assess the risk of calcium oxalate urolith formation in cats:

 

If a diet has an RSS for calcium oxalate of:
The urine produced by cats fed that diet is said to be:
And the risk for calcium oxalate urolith formation is:
Less than 1
Undersaturated
  • New calcium oxalate uroliths will not form
  • Existing calcium oxalate uroliths will not grow
Between 1 and 12
Metastable
  • New calcium oxalate uroliths will not form
  • Any existing calcium oxalate uroliths may grow
Over 12
Oversaturated
  • New calcium oxalate uroliths may form
  • Any existing calcium oxalate uroliths will grow

 

The table below provides some important RSS values for struvite and calcium oxalate:

To achieve the following:
Choose a diet which has an:
To avoid the risk of the alternative urolith, this diet should also have an:
Dissolve pure struvite uroliths
RSS for struvite less than 1.0
 RSS for calcium oxalate less than 12
Minimize the risk of struvite uroliths
RSS for struvite less than 2.5
RSS for calcium oxalate less than 12
Dissolve calcium oxalate uroliths
It is not physiologically possible to dissolve calcium oxalate uroliths. They must be removed surgically.
Minimize the risk of calcium oxalate uroliths
RSS for calcium oxalate less than 12
 RSS for struvite less than 2.5

 

Urinary Relative SuperSaturation (RSS) values for struvite and calcium oxalate in cats fed URINARY SOTM/MC(canned) and URINARY SO 13TM/MC (dry):

 
URINARY SOTM/MC IN GEL
URINARY SOTM/MC
 
Canned
Dry
RSS for struvite
0.53 +/- 0.31
0.05 +/- 0.004
RSS for calcium oxalate
1.6 +/- 0.42
0.76 +/- 0.11

URINARY SOTM/MC IN GEL (canned) and URINARY SO 30TM/MC (dry) are the first and only diets which have been clinically proven to aid in the management of both struvite and calcium oxalate urolithiasis in cats.

Idiopathic Cystitis:
A clinical study examined the recurrence of signs of lower urinary tract disease in 54 client-owned cats with idiopathic (or interstitial) cystitis. Recurrence rate for the year prior to the beginning of the study was 96%, with 52 cats having had at least one episode of LUTD signs in the previous year.

Signs did not recur in 89% of cats fed URINARY SOTM/MC IN GEL in canned format, while 61% of cats fed the URINARY SO 30TM/MC in dry format did not have a recurrence of signs over the 12 month trial period.

The proportion of cats in which clinical signs recurred was significantly lower in the canned diet group than in the dry group. Canned URINARY SOTM/MC IN GEL is the only diet proven to be beneficial in the management of feline idiopathic cystitis.


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Special Tips:

1. URINARY SOTM/MC IN GEL (canned) and URINARY SO 30TM/MC (dry) are designed to increase urine volume and dilution by increasing body water turnover. This diet is designed to increase water intake in the cat and increase the volume and frequency of urination.
2 It is important to counsel owners to expect changes in drinking and urination behavior and to make sure they understand that these changes are desirable and beneficial for their cat.
3 Fresh water should be readily available at all times.
4 Owners may need to clean their cat’s litter box more frequently.


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References:
Hawthorne AJ, Markwell PJ. The effect of dietary sodium content on water intake and urine composition in cats. Proceedings of the Waltham International Science Symposium, Bangkok, Thailand, October 28-31 2003 p 40.

Robertson WG, Jones JS, Heaton MA, et al. Predicting the crystallization potential of urine from cats and dogs with respect to calcium oxalate and magnesium ammonium phosphate (struvite). J Nutr 2002;132:1637S-41S.

Luckschander N, Iben C, Desprez C, et al. Does increasing dietary NaCl affect blood pressure in adult healthy cats? J Vet Intern Med 2002;16:788.

Robertson WG, Jones J, Heaton MA, et al. Predicting the calcium oxalate and magnesium ammonium phosphate crystallization potential of dog and cat urine. Waltham International Symposium - Pet Nutrition coming of Age - Canada. 24. (2001).

Smith BHE, Moodie S, Markwell PJ. Long term feeding of an acidifying diet to cats. J Vet Intern Med 2001;15:305.

Biourge V, Devois C, Morice G, et al. Une supplémentation en sel n’augmente pas l’indice des super-saturations urinaires en oxalate de Calcium chez les chats adultes sains. Congrès CNVSPA-AFVAC, SAVAB Lille 23-25 Novembre 2001 p295.

Luckshander N, Iben C, Gabler C, et al. Is there any effect of increasing dietary NaCl diet on blood pressure in healthy cats? Proceedings 11th ESCVIM Congress, Dublin Sept 5-8, 2001 p72.

Biourge V, Devois C, Morice G, et al. Dietary NaCl significantly increases urine volume but does not increase urinary calcium oxalate supersaturation in healthy cats. J Vet Intern Med 2001; 866.

Schwendenwein I, Iben C, Wagner E, et al. Effect of increasing dietary NaCl on fractional electrolyte clearance. Proceedings of 5th ESCVN Conference. Sursee, Switzerland. 2001, p93.

Devois C, Biourge V, Morice G, et al. Dietary NaCl supplementation does not increase urinary calcium oxalate relative supersaturation in health adult cats. BSAVA Congress 2001. Scientific Proceedings p 509.

Stevenson AE, Wrigglesworth DJ, Markwell PJ. Urine pH and Urinary Relative Supersaturation in Healthy Adult Cats. Urolithiasis 2000;818-820.

Reed CF, Markwell PJ, Jones CA, et al. Oral orthophosphate salt administration and its effect on feline urinary calcium oxalate formation and agglomeration. J Vet Intern Med; 2000;14:351.

Stevenson AE, Markwell PJ, Kasidas GP. Quantitative analysis of feline uroliths within Europe in 1998-99. J Vet Intern Med 2000;14:383.

Reed CF, Markwell PJ, Jones CA, et al. The effects of oral magnesium salt administration on urinary calcium oxalate crystallization and agglomeration in cats. J Vet Intern Med 2000;14:383.

Reed CF, Markwell PJ, Jones CA, et al. In vitro pyrophosphate supplementation in cat urine, and its effect on calcium oxalate formation and agglomeration. J Vet Intern Med 2000;14:384.

Devois C, Biourge V, Morice G, et al. Influence of various amounts of dietary NaCl on urinary Na, Ca, and oxalate concentrations and excretions in adult cats. Proceedings 10th ESVIM Congress, Neuchâtel, Suisse. Sept 14-16, 2000 p85.

Devois C, V Biourge, Morice G, et al. Struvite and oxalate activity product ratios and crystalluria in cats fed acidifying diets. Urolithiasis 2000. Feb 13-17. Cape Town 821-823.

Markwell PJ. Lower urinary tract diseases in cats: dietary and medical management. Wiener Tierarztlicher Monatschrift 1999;86: 8-12.

Markwell PJ, Smith BHE, McCarthy K. A non-invasive method for assessing the effect of diet on urinary calcium oxalate and struvite supersaturation in the cat. Animal Technology 1999;50: 61-67.

Markwell PJ, Buffington CA, Chew DJ, et al. Clinical evaluation of commercial acidified diets in the management of idiopathic cystitis in cats. J Am Vet Med Assoc 1999;214: 361-365.

Dumon H, Nguyen P, Martin L, et al. Influence of wet vs dry food on cat urinary pH: preliminary study. J Vet Intern Med 1999, abstract 138

Markwell PJ, Buffington CA, Chew DJ, et al. Clinical evaluation of commercial acidified diets in the management of idiopathic cystitis in cats. J Vet Inter Med 1998; 12: 222.

Markwell PJ, Buffington CT, Smith BH. The effect of diet on lower urinary tract disease in cats. J Nutr 1998;128:2753S-2757S.

Smith BH, Stevenson AE, Markwell PJ. Urinary relative supersaturations of calcium oxalate and struvite in cats are influenced by diet. J Nutr 1998;128:2763S-64S.

Smith BHE, Buffington CA, Markwell PJ. Comparative species urine pH data. J Vet Intern Med 1996;10:189.

Smith BHE, Stevenson AE, Markwell, PJ. Effect of diet on urinary saturation in cats. Proceedings of 2nd FECAVA Congress 1995;359-360.

Filippich LJ. Feline lower urinary tract disease: clinical dietary study. Australian Veterinary Practitioner 1994;24:16-22.

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