Search

Objective: To evaluate the long-term risk of recurrence of calcium oxalate (CaOx) cystic calculi in dogs of various breeds fed 1 of 2 therapeutic diets., Design: Retrospective cohort study. Animals-135 dogs with a history of CaOx cystic calculi., Procedures: Medical records for 4 referral hospitals were searched to identify dogs that had had CaOx cystic calculi removed. Owners were contacted and medical records evaluated to obtain information on postoperative diet, recurrence of signs of lower urinary tract disease, and recurrence of cystic calculi. Dogs were grouped on the basis of breed (high-risk breeds, low-risk breeds, and Miniature Schnauzers) and diet fed after removal of cystic calculi (diet A, diet B, and any other diet [diet C], with diets A and B being therapeutic diets formulated to prevent recurrence of CaOx calculi)., Results: Breed group was a significant predictor of calculi recurrence (as determined by abdominal radiography or ultrasonography), with Miniature Schnauzers having 3 times the risk of recurrence as did dogs of other breeds. Dogs in diet group A had a lower prevalence of recurrence than did dogs in diet group C, but this difference was not significant in multivariable analysis., Conclusions and Clinical Relevance: Results indicated that Miniature Schnauzers had a higher risk of CaOx cystic calculi recurrence than did dogs of other breeds. In addition, findings suggested that diet may play a role in decreasing recurrence, but future prospective studies are needed to validate these observations.

Objective: To evaluate pretreatment clinical and laboratory findings in dogs with naturally occurring primary hyperparathyroidism., Design: Retrospective study., Animals: 210 dogs with primary hyperparathyroidism and 200 randomly selected, age-matched control dogs that did not have primary hyperparathyroidism., Procedure: Medical records for dogs with primary hyperparathyroidism were reviewed for signalment; clinical features; and results of clinicopathologic testing, serum parathyroid hormone assays, and diagnostic imaging., Results: Mean age of the dogs with primary hyperparathyroidism was 11.2 years (range, 6 to 17 years). The most common clinical signs were attributable to urolithiasis or urinary tract infection (ie, straining to urinate, increased frequency of urination, and hematuria). Most dogs (149 [71%]) did not have any observable abnormalities on physical examination. All dogs had hypercalcemia, and most (136 [65%]) had hypophosphatemia. Overall, 200 of the 210 (95%) dogs had BUN and serum creatinine concentrations within or less than the reference range, and serum parathyroid hormone concentration was within reference limits in 135 of 185 (73%) dogs in which it was measured. Urolithiasis was identified in 65 (31 %) dogs, and urinary tract infection was diagnosed in 61 (29%). Mean serum total calcium concentration for the control dogs-was significantly lower than mean concentration for the dogs with primary hyperparathyroidism, but mean BUN and serum creatinine concentrations for the control dogs were both significantly higher than concentrations for the dogs with primary hyperparathyroidism., Conclusions and Clinical Relevance: Results suggest that urolithiasis and urinary tract infection may be associated with hypercalcemia in dogs-with primary hyperparathyroidism, but that development of renal insufficiency is uncommon.

Objective: To test the hypothesis that urate uroliths are uncommonly detected in female Dalmatians, compared with males., Design: Case-control study., Sample Population: Medical records of dogs evaluated at veterinary teaching hospitals in North America from 1981 to 2002 and compiled by the Veterinary Medical Database, and records of dogs with uroliths submitted for quantitative analyses to the Minnesota Urolith Center from 1981 to 2002., Procedures: Crude odds ratios (ORs) and 95% confidence intervals were calculated to assess whether sex (male vs female) was a risk factor for urate urolithiasis., Results: In Dalmatians evaluated by veterinary teaching hospitals in North America, males were more likely (OR, 13.0) to form uroliths, compared with females. In Dalmatians that formed uroliths analyzed by the Minnesota Urolith Center, males were more likely (OR, 14.0) to form urate uroliths, compared with females. In all dogs (Dalmatian and non-Dalmatian) that formed uroliths analyzed by the Minnesota Urolith Center, males were also more likely (OR, 48.0) to form urate uroliths, compared with females., Conclusions and Clinical Relevance: When conducting studies and formulating generalities about urate urolithiasis in Dalmatians, it is important to consider sex-related differences in urolith occurrence. Long-term dietary or drug protocols designed to minimize formation of urate uroliths in male Dalmatians may not be warranted in female Dalmatians.

Objective: To determine hospital proportional morbidity rates (HPMR) for urethral obstructions, urethral plugs or urethroliths, and urethrostomies in cats in veterinary teaching hospitals (VTH) in Canada and the United States between 1980 and 1999., Design: Epidemiologic study., Animals: 305,672 cats evaluated at VTH., Procedures: Yearly HPMR were determined for cats with urethral obstructions, urethral plugs or urethroliths, or urethrostomies from data compiled by the Purdue Veterinary Medical Database. The test for a linear trend in proportions was used., Results: Urethral obstructions were reported in 4,683 cats. Yearly HPMR for urethral obstructions declined from 19 cases/1,000 feline evaluations in 1980 to 7 cases/1,000 feline evaluations in 1999. Urethral plugs or urethroliths affected 1,460 cats. Yearly HPMR for urethral plugs or urethroliths decreased from 10 cases/1,000 feline evaluations in 1980 to 2 cases/1,000 feline evaluations in 1999. A total of 2,359 urethrostomies were performed. Yearly HPMR for urethrostomies decreased from 13 cases/1,000 feline evaluations in 1980 to 4 cases/1,000 feline evaluations in 1999., Conclusions and Clinical Relevance: Frequency of feline urethrostomies performed at VTH in Canada and the United States declined during the past 20 years and paralleled a similar decline in frequency of urethral obstructions and urethral plugs or urethroliths. These trends coincide with widespread use of diets to minimize struvite crystalluria in cats, which is important because struvite has consistently been the predominant mineral in feline urethral plugs during this period.

Objective: To identify dietary factors associated with the increase in occurrence of calcium oxalate (CaOx) uroliths and the decrease in occurrence of magnesium ammonium phosphate (MAP) uroliths in cats., Design: Case-control study., Animals: 173 cats with CaOx uroliths, 290 cats with MAP uroliths, and 827 cats without any urinary tract diseases., Procedure: Univariate and multivariate logistic regression were performed., Results: Cats fed diets low in sodium or potassium or formulated to maximize urine acidity had an increased risk of developing CaOx uroliths but a decreased risk of developing MAP uroliths. Additionally, compared with the lowest contents, diets with the highest moisture or protein contents and with moderate magnesium, phosphorus, or calcium contents were associated with decreased risk of CaOx urolith formation. In contrast, diets with moderate fat or carbohydrate contents were associated with increased risk of CaOx urolith formation. Diets with the highest magnesium, phosphorus, calcium, chloride, or fiber contents and moderate protein content were associated with increased risk of MAP urolith formation. On the other hand, diets with the highest fat content were associated with decreased risk of MAP urolith formation., Conclusions and Clinical Relevance: Results suggest that diets formulated to contain higher protein, sodium, potassium, moisture, calcium, phosphorus, and magnesium contents and with decreased urine acidifying potential may minimize formation of CaOx uroliths in cats. Diets formulated to contain higher fat content and lower protein and potassium contents and with increased urine acidifying potential may minimize formation of MAP uroliths.

Objective: To determine whether breed, age, sex, or reproductive status (i.e., neutered versus sexually intact) was associated with the apparent increase in prevalence of calcium oxalate (CaOx) uroliths and the decrease in prevalence of magnesium ammonium phosphate (MAP) uroliths in cats over time., Design: Case-control study., Animals: Case cats consisted of cats with CaOx (n = 7,895) or MAP (7,334) uroliths evaluated at the Minnesota Urolith Center between 1981 and 1997. Control cats consisted of cats without urinary tract disease admitted to veterinary teaching hospitals in the United States and Canada during the same period (150,482)., Procedure: Univariate and multivariate logistic regression were performed., Results: British Shorthair, Exotic Shorthair, Foreign Shorthair, Havana Brown, Himalayan, Persian, Ragdoll, and Scottish Fold cats had an increased risk of developing CaOx uroliths, as did male cats and neutered cats. Chartreux, domestic shorthair, Foreign Shorthair, Himalayan, Oriental Shorthair, and Ragdoll cats had an increased risk of developing MAP uroliths, as did female cats and neutered cats. Cats with CaOx uroliths were significantly older than cats with MAP uroliths., Conclusions and Clinical Relevance: Results suggest that changes in breed, age, sex, or reproductive status did not contribute to the apparent reciprocal relationship between prevalences of CaOx and MAP uroliths in cats during a 17-year period. However, cats of particular breeds, ages, sex, and reproductive status had an increased risk of developing CaOx and MAP uroliths.

Objective: To test the hypothesis that breed, age, sex, body condition, and environment are risk factors for development of calcium oxalate uroliths in dogs., Design: Case-control study., Animals: 1,074 dogs that formed calcium oxalate uroliths and 1,724 control dogs that did not have uroliths., Procedure: A validated multiple-choice questionnaire was designed to collect information from veterinarians and owners within 1 year of the date of urolith detection concerning signalment and environment of the dogs. Univariate and multivariate analyses were performed to calculate odds ratios to assess whether breed, age, sex, body condition, and environment were risk factors for calcium oxalate urolith formation., Results: Middle-aged (8- to 12-year-old) castrated male dogs had increased risk for formation of calcium oxalate uroliths. Urolith formation was also associated with increasing age. Dogs of certain breeds, including Miniature and Standard Schnauzer, Lhasa Apso, Yorkshire Terrier, Bichon Frise, Shih Tzu, and Miniature and Toy Poodle, had increased risk for developing calcium oxalate uroliths. Overweight dogs also had increased risk., Conclusions and Clinical Relevance: Knowledge of patient and environmental risk factors for development of calcium oxalate uroliths may facilitate development of surveillance strategies that result in earlier detection of this disease. Modification of environmental factors and body weight may minimize calcium oxalate urolith formation and recurrence.

Objective: To determine, among dogs with urolithiasis, whether dogs that had hyperadrenocorticism would be more likely to have calcium-containing uroliths than would dogs that did not have clinical evidence of hyperadrenocorticism., Design: Retrospective case-control study., Animals: 20 dogs that had urolithiasis and hyperadrenocorticism and 42 breed-matched dogs that had urolithiasis but did not have clinical evidence of hyper-adrenocorticism., Procedure: Signalment, urolith composition, results of bacterial culture of urine, and results of adrenal axis tests were recorded. A multivariate logistic regression model was created, including terms for age, sex, and hyperadrenocorticism. The outcome variable was presence or absence of calcium-containing uroliths., Results: Among dogs with urolithiasis, those that had hyperadrenocorticism were 10 times as likely to have calcium-containing uroliths as were dogs that did not have clinical evidence of hyperadrenocorticism (odds ratio, 10.5; 95% confidence interval, 1.5 to 23.4). Neutered and sexually intact females were less likely to have calcium-containing uroliths than were neutered males (odds ratios, 0.041 [95% confidence interval, 0.0057 to 0.29] and 0.024 [95% confidence interval, 0.0012 to 0.51, respectively)., Clinical Implications: Prompt diagnosis and treatment of hyperadrenocorticism may decrease prevalence of calcium-containing uroliths in dogs.

Objective: to test the hypothesis that breed, sex and age of cats, and anatomic location of uroliths are risk factors for calcium oxalate and magnesium ammonium phosphate urolithiasis., Design: Retrospective case-control study., Sample Population: Records of 3,498 feline urolith accessions submitted between September 1982 and September 1992., Procedure: Mineral composition of feline uroliths was quantitatively analyzed. Odds ratios and 95% confidence intervals were calculated for breed, sex, age, and urolith location as risk factors for calcium oxalate and magnesium ammonium phosphate urolith formation. The population at risk was defined as all cats for which that type of urolith had been submitted. The control population was all cats for which uroliths had been submitted, excluding cats with the type of urolith being evaluated., Results: Burmese, Persian, and Himalayan breeds were at higher risk for developing calcium oxalate uroliths, but at reduced risk for developing magnesium ammonium phosphate uroliths. Compared with females, neutered male cats had a higher risk for developing calcium oxalate uroliths, but a reduced risk for developing magnesium ammonium phosphate uroliths. The risk for calcium oxalate urolith formation increased with age. One- to 2-year-old female cats had the highest risk for magnesium ammonium phosphate uroliths. Uroliths removed from the kidneys were more likely to be composed of calcium oxalate than of magnesium ammonium phosphate., Clinical Implications: Breed, sex, and age of cats, and anatomic location of uroliths should be considered when evaluating risk of calcium oxalate and magnesium ammonium phosphate urolithiasis in urolith-forming cats.

Objective: To evaluate dietary and environmental factors as potential risk factors for calcium oxalate urolithiasis in cats., Design: Case-control study., Animals: 84 cats with uroliths composed of at least 90% calcium oxalate and 258 age- and gender-matched control cats., Procedure: Owners of cats with calcium oxalate urolithiasis and control cats were surveyed between November 1990 and August 1992. Owners completed a standard questionnaire administered during a single telephone interview. Data collected included information regarding signalment, environment, urination and defecation, diet, and medical history., Results: Calcium oxalate uroliths tended to develop in middle- to older-aged, domestic shorthair cats of typical weight. A gender predilection was not detected. Factors associated with an increase in the risk of calcium oxalate urolithiasis in cats were feeding urine-acidifying diets, feeding a single brand of cat food without providing additional foods or table scraps, maintaining cats in an indoor-only environment, and being of the Persian breed., Clinical Implications: Control of diet and environment may help prevent calcium oxalate urolithiasis.

Data were evaluated from all dogs admitted to the University of Minnesota Veterinary Teaching Hospital (UMVTH) between June 1, 1981 and Dec 31, 1991. During this period, uroliths were retrieved and analyzed from 452 of 37,574 dogs admitted. The odds that uroliths from Bulldogs were composed of cystine were 32.3 times greater than for other breeds evaluated. The odds that a Bulldog admitted was affected with cystine uroliths were 154.1 times greater than for other breeds. Cystine uroliths were retrieved only from male Bulldogs. The odds that uroliths from Bulldogs were composed of urate were 7.9 times greater than for other breeds. The odds that a Bulldog admitted was affected with urate uroliths were 43.0 times greater than for other breeds. Male Bulldogs were 14.3 times more likely to be affected with urate uroliths than were females. The odds that uroliths from Dalmatians were composed of urate were 228.9 times greater than for other breeds. The odds that a Dalmation admitted was affected with urate uroliths were 122.4 times greater than for other breeds. Male Dalmatians were 16.4 times more likely to be affected with urate uroliths than were females. Data also were evaluated from files of canine uroliths submitted to the Minnesota Urolith Center for quantitative mineral analysis between June 1, 1981 and Dec 31, 1991. During this period, 94 of 11,188 uroliths analyzed were obtained from Bulldogs and 387 were obtained from Dalmatians. The odds that uroliths retrieved from Bulldogs were composed of cystine were 40.7 times greater than for other breeds. Cystine uroliths were retrieved only from male Bulldogs.(ABSTRACT TRUNCATED AT 250 WORDS)

From July 1, 1981 to December 31, 1990 the Urinary Stone Analysis Laboratory, School of Veterinary Medicine, University of California received 292 urinary calculi from 275 Dalmations (14 females, 14 episodes; 261 males, 278 episodes). The mean age of dogs at the time of the first episode of calculus formation was 4.5 years for males and 5.5 years for females. Bacteria were isolated from 22 of 49 calculi (45%). The bacteria were gram-positive with 2 exceptions; coagulase-positive staphylococci accounted for 62.5% of the isolates. Polarized light microscopy was used to determine the mineral content of the calculi. One hundred ninety three calculi were 100% urate; 78 calculi contained > or = 50% urate in 1 or more layers and were classified as mixed urate calculi; 7 calculi contained < 50% urate in all layers; and 14 calculi contained no urate. The secondary minerals most commonly encountered in mixed urate calculi were struvite (77%, 60 of 78 calculi), and oxalate (17%, 13 of 78 calculi). There were 65 struvite-containing calculi, 16 oxalate-containing calculi, 7 apatite-containing calculi, 5 silica-containing calculi, and 1 calculus specimen was composed of 100% cystine. The risk of forming urate-containing calculi was high in Dalmations, whereas the risk of forming calculi containing other minerals was consistently lower in Dalmations than in other breeds. X-ray diffraction and high pressure liquid chromatography were performed on all calculi from dogs known to have been given allopurinol (n = 19).(ABSTRACT TRUNCATED AT 250 WORDS)

One hundred fifty specimens of urinary calculi from 150 cats were analyzed by at least 1 of 4 quantitative methods. Struvite (magnesium ammonium phosphate) was the predominant mineral substance encountered, with 104 (69%) of the calculi being composed entirely of struvite and 23 (15%) being composed partially of struvite. Most (93%) of the calculi were located in the urinary bladder. Growth of bacteria was observed in samples from calculi or urine from 30 (41%) of 74 cats. Coagulase-positive staphylococci were isolated from the urine or calculi from 17 cats (45% of bacteria isolated). Ten other bacterial species were isolated. Median and mean ages of the cats were 5.0 and 5.1 years, respectively. Domestic short-hair and domestic longhair breeds predominated. Fifty-seven percent of the calculi came from females, 43% from males. The distribution by gender did not differ significantly (P greater than 0.2) among the 3 groups (domestic shorthair, domestic longhair, and other). However, the distribution of struvite calculi differed significantly (chi 2 = 15.5, P less than 0.001) by age and gender; among cats less than or equal to 2 years of age, males predominated 2:1 over females, and among cats greater than 2 years of age, females predominated by nearly 3:1 over males. When compared with the general population, females greater than 2 years old were significantly (chi 2 = 15.4, P less than 0.001) overrepresented.

Data related to rates of disease and their associated costs were collected for 12 months from 2 sheep feedlots in northern Colorado. There was an apparent seasonal occurrence of many of the diseases. Pneumonia, enterotoxemia, acidosis, and transport tetany accounted for most of the diseases seen in these feedlots and were responsible for most of the economic losses. There was a large difference in the incidence of diseases between the 2 feedlots and in the expenditures for disease prevention between the 2 feedlots.

In a retrospective analysis of 438 cases of canine urolithiasis, a total of 561 urolithic episodes were found to have occurred in a 6 1/2-year period. The hospital incidence of urolithiasis during that period, defined as the proportion of dogs hospitalized with urolithiasis to the total number of dogs hospitalized, was 2.8%. The major chemical component of the calculus in 307 dogs was phosphate; in 95 dogs, cystine; in 21 dogs, urate; in 12 dogs, oxalate; and in 3 dogs, carbonate. The Miniature Schnauzer, Dachsund, Dalmatian, Pug, Bulldog, Welsh Corgi, Beagle, and Bassett Hound were breeds that had a significantly higher (P less than 0.05) incidence of calculi than did breeds of other dogs hospitalized. Predisposition for calculi, by sex, was not found. Most dogs with calculi were between 3 and 7 years old. Most calculi were radiopaque and were located in the bladder or in the bladder and urethra. Specimens for bacteriologic culture were obtained by catheterization or by swabbing of tissue at the surgical site. Of 259 specimens obtained, 181 were culture-positive. The most common organisms isolated were Staphylococcus spp, Escherichia coli, Proteus spp, Streptococcus spp, and Klebsiella spp. Most of the bacteria were sensitive to gentamicin, chloramphenicol, nitrofurantoin, cephalothin, and methanamine mandelate.