Study Start Date: 03/01/2016
Study End Date: 03/31/2018

Use of Canine Struvite Dissolution Diet in the Management of Infection Induced Struvite Stones in Dogs

We invite your dog to take part in this clinical trial because to evaluate the efficacy of a therapeutic diet for struvite dissolution in dogs. By feeding the test diet and antibiotics we hypothesize that dissolution of canine struvite bladder stones will occur within a 12-week period.

1. At the enrollment visit, ~3–5 ml of blood will be taken (usually from a vein in the neck or leg) as well as urine (by inserting a needle into the bladder; cystocentesis). Abdominal x-rays and ultrasound will also be performed at that time to document the size of the bladder stone(s). Sedation may be required to obtained diagnostic quality images on your dog. We will discuss this with you if we feel it is necessary. A cleansing enema may also be required if stool in the colon is obscuring the stones in the bladder.
2. Antibiotics and diet will be provided free of charge to you during the study duration.
3. Enough of the test diet will be dispensed to you to feed to your dog to maintain stable body weight.
4. Recheck evaluations will be scheduled at 2, 4, 8 and 12 weeks. At those visits, urine will be collected and x-rays performed. The size of the bladder stone(s) will be monitored and recorded. Your dog will stay enrolled in the study until the stones have: a) dissolved or b) if failure has been documented (no dissolution by week 12).

Study Design:
Prospective,Blinded

Sample Size:
We require 20 dogs total.  We have recruited 16 as of this posting and require an additional 4 dogs.

Inclusion Criteria:

• lower urinary tract (LUT) signs plus the presence of radiopaque cystic calculi (1 or more) in the bladder
• high numbers of urease-producing bacteria based on quantitative aerobic urine culture (> 1000 cfu/ml from a cystocentesis sample), such as Staphylococcus, Proteus, Klebsiella and some Enterococcus spp.
• client consent form signed
• The client must be willing to feed exclusively the test diet (provided free of charge) for up to 12 weeks, to keep a daily food diary at the designated time points, and return for specified rechecks.
• The client must be willing to return to the clinic for scheduled evaluations periodically for up to 12 weeks
• The client must be willing to allow the clinician to obtain urine by cystocentesis at the designated time points. The clinician must be able to obtain urine by cystocentesis at the designated time points.

Exclusion Criteria:

• Consumption of another urolith dissolution food within the previous 3 weeks
• Already on antibiotics > 5 days or glucocorticosteroids within the past 2 weeks
• Infection with C. urealyticum
• Uroliths in kidneys, ureters, or urethra
• Urethral obstruction
• Radiolucent urinary stones (i.e., only visible by ultrasonography)
• Urinary tract mass(es) that are suggestive for neoplasia and/or profound polypoid cystitis.
• Systemic disease: diabetes mellitus, Cushing’s disease, congestive heart failure, chronic kidney disease, liver disease, active pancreatitis, or a history of pancreatitis where a dietary fat content lower than 3.3 g/100 kcal would be indicated (based on history obtained and reviewed by board certified nutritionists).
• Malignancy
• Treatment with any drug or supplement that could potentially affect expression of LUT signs (e.g., antihistamines, antidepressants, anti-inflammatories, glycosaminoglycans, or nutritional supplements) within 3 days of enrollment. Allow 2–3 days of analgesics if needed.

Study Endpoints:
Urolith dissolution or failure (no dissolution by week 12)

External Study URL:
http://www.vetmed.ucdavis.edu/clinicaltrials/current_trials/by_service/nutrition.cfm

Files for Download:
Clinical Bladder Stones pdf

Costs/Reimbursements
The study will:

• Cover all costs associated with participation in the study        
• Provide food free of charge for the duration of the study
• Cover costs of stone removal if the dog fails the study
• Provide $200 worth of sponsor dog food to the referring veterinarian as a “thank you” for sending the referral