Urolith in Thailand vs. Global Perspective and How to Manage Them
Objective of Presentation
To understand about urolith formation
Learn how different types of uroliths from each part of the world
Learn how urolith prevalence in Thailand different from others
Learn how to manage various types of uroliths
Urolith Formation
Urolith formation is unlike a basic science project. The process is consisted of many factors. Decrease in crystal inhibitors and increase in crystal promoters in the oversaturation urine will create crystal formation. Then, crystal retention and crystal aggregation will promote the crystal growth into urolith occurrence. Specific breed, age, and gender are proven to be risk factors that veterinarians need to be aware for early detection. Overweight, less exercise, and dietary compositions also are recognized as reversible risk factors. Therefore, urolith formation is the multifactorial causes.1
Types of Uroliths
A urolith without a nidus or shell of different composition which contains more than or equal to 70% of one type of mineral is classified as that mineral type. Therefore, the Minnesota Urolith Center divided the common urolith types as magnesium ammonium phosphate, calcium oxalate, calcium phosphate, purine, cystine, and silica. Mixed urolith is classified as a urolith with less than 70% of one specific mineral type. Likewise, compound urolith is classified as a urolith with a nidus or stone composed of one or more mineral types and surrounding layers consisted of different mineral composition.2 Therefore, the quantitative urolith analysis is the important tool for monitoring urolith recurrence.
Uroliths in Global Perspective and Thailand
Lulich et al. (2013) reported the global changes in canine urolith occurrences from 6 continents during 2009–2010 compared with the period of 1999–2000. In global perspective, trend of calcium oxalate and cystine urolith submissions to the Minnesota Urolith Center were increased. In contrast, trend of magnesium ammonium phosphate and purine submissions were decreased. Calcium oxalate is the most common urolith type during 2009–2010. Magnesium ammonium phosphate and purine is the second and third most common type. At the same time, trend of calcium oxalate and silica urolith submissions from Asia to the Minnesota Urolith Center were increased. In contrast, trend of magnesium ammonium phosphate, purine, and cystine submissions were decreased. Magnesium ammonium phosphate is the most common urolith type during 2009–2010. Calcium oxalate and purine is the second and third most common type.3 In Thailand, magnesium ammonium phosphate is the most common urolith type in dogs and cats. Calcium oxalate and compound urolith is the second and third most common type.
Management of Uroliths
Magnesium ammonium phosphate urolith occurrence is planned to manage with antibiotic control of bacterial urinary tract infection in dogs and with dietary dissolution and prevention in cats. Calcium oxalate and calcium phosphate occurrence can be delayed the recurrence with the prevention diet after surgical removal. Purine and cystine are proven to dissolve and prevent successfully with a specific diet. Compound urolith is controlled by aiming to control the original mineral type at the nidus or stone.4,5
The abdominal radiography, double contrast radiography, urinalysis, and urine culture are the important tools for diagnosis, surveillance, and monitoring of urolith formation. The technique of retrograde urohydropropulsion is used to bring the uroliths from urethra back to urinary bladder and then performing the surgical removal.6 Likewise, the technique of voiding urohydropropulsion is proven to be a very useful tool for urolith removal without surgery.7
Therefore, patients with urolith formation should be monitored routinely every 2–3 months. Modification of diet, risk factor reversibility, and certain schedule of surveillance should be planned and monitored systemically. When they are detected the small urolith formation recurrence, many techniques can be used to help patients to avoid surgical.
References
1. Lulich JP, et al. Epidemiology of canine calcium oxalate uroliths. Identifying risk factors. Vet Clin North Am Small Anim Pract. 1999;29:113–122.
2. Osborne CA, et al. Analysis of 77,000 canine uroliths. Perspectives from the Minnesota Urolith Center. Vet Clin North Am Small Anim Pract. 1999;29:17–38.
3. Lulich JP, et al. Recent shifts in the global proportions of canine uroliths. Vet Rec. 2013;172:363–370.
4. Lekcharoensuk C, et al. Patient and environmental factors associated with calcium oxalate urolithiasis in dogs. J Am Vet Med Assoc. 2000;217:515–519.
5. Lekcharoensuk C, et al. Association between patient-related factors and risk of calcium oxalate and magnesium ammonium phosphate urolithiasis in cats. J Am Vet Med Assoc. 2000;217:520–522.
6. Osborne CA, et al. Canine retrograde urohydropropulsion. Lessons from 25 years of experience. Vet Clin North Am Small Anim Pract. 1999;29:267–281.
7. Lulich JP, et al. Voiding urohydropropulsion. Lessons from 5 years of experience. Vet Clin North Am Small Anim Pract. 1999;29:283–291.