Factors associated with hematuric struvite crystalluria in cats.

OBJECTIVES: The aim of the study was to identify any dietary, signalment, geographic and clinical factors associated with hematuric struvite crystalluria (HSC) in a population of cats that visit general care veterinary hospitals in the USA. METHODS: In total, 4032 cats that had a first-time diagnosis of HSC and 8064 control cats with no history of hematuria or crystalluria were identified from medical records of all cats examined between 2007 and 2011 at 790 US veterinary hospitals. Extracted variables included age, sex, neuter status, breed, diet, urinalysis results and history of cystitis. Potential associations between these variables and HSC were estimated. RESULTS: Controlling for other factors, young cats fed a dry diet had an increased likelihood of HSC relative to young cats fed a non-dry diet. However, as age increased, the likelihood of HSC declined for cats fed a dry diet and increased for cats fed a non-dry diet. Moreover, the odds of HSC were significantly greater when cats were unneutered (vs neutered; odds ratio [OR] 45.52) or had a thin (vs heavy) body condition (OR 23.81), diagnosis of cystitis (OR 2.84), urine protein concentration >30 mg/dl (OR 4.72), alkaline (vs neutral) urine pH (OR 3.34), pyuria (OR 23.67) or bacteriuria (OR 2.24). CONCLUSIONS AND RELEVANCE: The present study provides estimates of the strengths of association between HSC and certain signalment and clinical characteristics of cats. This information could help clinicians to perform a more directed screening for struvite crystalluria in certain cat populations. Follow-up studies that build on the findings of this study could explore the clinical importance of HSC in cats.

Survival analysis to evaluate associations between periodontal disease and the risk of development of chronic azotemic kidney disease in cats evaluated at primary care veterinary hospitals.

OBJECTIVE To examine potential associations between periodontal disease (PD) and the risk of development of chronic azotemic kidney disease (CKD) among cats and determine whether the risk of CKD increases with severity of PD. DESIGN Retrospective cohort study. ANIMALS 169, 242 cats. PROCEDURES Cats were evaluated ≥ 3 times at any of 829 hospitals from January 1, 2002, through June 30, 2013. Cats with an initial diagnosis of PD of any stage (n = 56,414) were frequency matched with cats that had no history or evidence of PD (112,828) by age and year of study entry. Data on signalment, PD, and other conditions potentially related to CKD were extracted from electronic medical records. Cox proportional hazards modeling was used to estimate the association of PD with CKD after controlling for covariates. RESULTS PD was associated with increased risk of CKD; risk was highest for cats with stage 3 or 4 PD. Risk of CKD increased with age. Purebred cats had greater risk of CKD than mixed-breed cats. General anesthesia within the year before study exit and diagnosis of cystitis at any point prior to study exit (including prior to study entry) were each associated with increased CKD risk. Diagnosis of diabetes mellitus or hepatic lipidosis at any point prior to study exit was associated with decreased CKD risk. CONCLUSIONS AND CLINICAL RELEVANCE The findings supported the benefit of maintaining good oral health and can be useful to veterinarians for educating owners on the importance of preventing PD in cats.

Risk factors associated with calcium oxalate urolithiasis in dogs evaluated at general care veterinary hospitals in the United States.

Calcium oxalate urolithiasis results from the formation of aggregates of calcium salts in the urinary tract. Difficulties associated with effectively treating calcium oxalate urolithiasis and the proportional increase in the prevalence of calcium oxalate uroliths relative to other urolith types over the last 2 decades has increased the concern of clinicians about this disease. To determine factors associated with the development of calcium oxalate urolithiasis in dogs evaluated at general care veterinary hospitals in the United States, a retrospective case-control study was performed. A national electronic database of medical records of all dogs evaluated between October 1, 2007 and December 31, 2010 at 787 general care veterinary hospitals in the United States was reviewed. Dogs were selected as cases at the first-time diagnosis of a laboratory-confirmed urolith comprised of at least 70% calcium oxalate (n=452). Two sets of control dogs with no history of urolithiasis diagnosis were randomly selected after the medical records of all remaining dogs were reviewed: urinalysis examination was a requirement in the selection of one set (n=1808) but was not required in the other set (n=1808). Historical information extracted included urolith composition, dog's diet, age, sex, neuter status, breed size category, hospital location, date of diagnosis, and urinalysis results. Multivariable analysis showed that the odds of first-time diagnosis of calcium oxalate urolithiasis were significantly (P<0.05) greater for dogs<7 years, males (OR: 7.77, 95% CI: 4.93-12.26), neutered (OR: 2.58, 1.44-4.63), toy- vs. medium-sized breeds (OR: 3.15, 1.90-5.22), small- vs. medium-sized breeds (OR: 3.05, 1.83-5.08), large- vs. medium-sized breeds (OR: 0.05, 0.01-0.19), and those with a diagnosis of cystitis within the previous year (OR: 6.49, 4.14-10.16). Urinary factors significantly associated with first-time diagnosis of calcium oxalate urolithiasis were acidic vs. basic pH (OR: 1.94, 1.22-3.10), presence of RBCs (OR: 6.20, 3.91-9.83) or WBCs (OR: 1.62, 1.03-2.54), and protein concentration>30 mg/dL (OR: 1.55, 1.04-2.30). Patient demographics and urinalysis results are important factors that can support risk assessment and early identification of canine oxalate urolithiasis. Therefore, periodic urolith screening and monitoring of urine parameters should be encouraged for dogs at risk of developing these uroliths.

Risk factors associated with the development of chronic kidney disease in cats evaluated at primary care veterinary hospitals.

OBJECTIVE: To identify risk factors associated with diagnosis of chronic kidney disease (CKD) in cats. DESIGN: Retrospective case-control study. ANIMALS: 1,230 cats with a clinical diagnosis of CKD, serum creatinine concentration > 1.6 mg/dL, and urine specific gravity < 1.035 and 1,230 age-matched control cats. PROCEDURES: Data on putative risk factors for CKD were extracted for multivariate logistic regression analysis from the medical records of cats brought to 755 primary care veterinary hospitals. For a subset of cats evaluated 6 to 12 months prior to the date of CKD diagnosis or control group inclusion, the percentage change in body weight between those dates as well as clinical signs at the earlier date were analyzed for associations with CKD development. RESULTS: Risk factors for CKD in cats included thin body condition, prior periodontal disease or cystitis, anesthesia or documented dehydration in the preceding year, being a neutered male (vs spayed female), and living anywhere in the United States other than the northeast. The probability of CKD decreased with increasing body weight in nondehydrated cats, domestic shorthair breed, and prior diagnosis of diabetes mellitus and increased when vomiting, polyuria or polydipsia, appetite or energy loss, or halitosis was present at the time of diagnosis or control group inclusion but not when those signs were reported 6 to 12 months earlier. Median weight loss during the preceding 6 to 12 months was 10.8% and 2.1% in cats with and without CKD, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: The probability of CKD diagnosis in cats was influenced by several variables; recent weight loss, particularly in combination with the other factors, warrants assessment of cats for CKD.

A moderate fat, low-energy dry expanded diet reduces gain in body condition score when fed as part of a post neutering weight-control regimen in growing pet cats.

Neutering of cats has been associated with significant weight gain in the weeks following surgery. The present study aimed to evaluate the effectiveness of a moderate fat, low-energy dry expanded diet in reducing weight gain in growing pet cats when fed as part of a weight-control regimen over the 6 months post-neutering. Cats in participating primary care veterinary hospitals were enrolled at neutering and assigned to receive one of the two dietary treatments based on the hospital of origin. Owners of cats in the treatment group were instructed to feed the trial diet at maintenance (324·7 kJ/kg BW(0·711) per d). Instructions for the control group were to feed the cat's regular diet according to the manufacturer's recommendations. Body weight and condition were evaluated by veterinarians at enrolment, 2-weeks, and 1-4 and 6 months after surgery. Body condition score (five-point scale) was compared between enrolment and each subsequent visit, controlling for enrolment age and sex. Percentage change in body weight was evaluated via multivariate mixed modelling to account for repeated measures. A total of 187 cats (eighty-seven females and 100 males) with a mean age of 5·2 (sd 0·8) months and mean weight of 2·8 (sd 0·6) kg from fifty-one hospitals completed the trial. The odds of being scored as overweight were 4·1 times as great for cats in the control v. treatment groups (95 % CI 2·1, 8·2). Percentage change in body weight differed significantly with enrolment age (P = 0·007) and approached significance between diet groups (P = 0·08). Cats fed the trial diet had a significantly reduced incidence of overweight in the 6 months following neutering.

Evaluation of risk factors associated with suture-nidus cystoliths in dogs and cats: 176 cases (1999-2006).

OBJECTIVE: To characterize and evaluate risk factors for suture-associated cystoliths in dogs and cats. DESIGN: Retrospective case-control study. Animals-163 dogs and 13 cats with suture-associated cystoliths and 326 control dogs and 26 control cats with non-suture-associated cystoliths. PROCEDURES: Submissions to the Canadian Veterinary Urolith Centre received from 1999 to 2006 were reviewed. Case dogs and cats had cystoliths associated with visible suture or with hollow, cylindrical channels or suture knot impressions consistent with dissolved suture. Control dogs and cats had at least a single recurrent non-suture-associated cystolith submitted closest in time to the sample case. Associations among cystolith composition, recurrence times, sex, age, and breed were evaluated. RESULTS: Cases consisted of 92 dogs and 7 cats with visible suture and 71 dogs and 6 cats with dissolved suture. Suture-associated cystoliths represented 0.6% of canine cystoliths, 9.4% of recurrent canine cystoliths, 0.17% of feline cystoliths, and 4% of recurrent feline cystoliths. Sexually intact and neutered males were at increased odds of suture-associated cystoliths, relative to spayed female dogs. Shih Tzus, Lhasa Apsos, and Pomeranians were significantly predisposed to form suture-associated cystoliths. In dogs, compound suture-associated cystoliths were significantly more likely than other cystolith types (OR, 8.6). Dogs with suture-associated cystoliths had significantly shorter recurrence times than did control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Suture remnants in the bladder have an important role in recurrent cystolithiasis in dogs. Identification of risk factors is important for avoiding recurrence of iatrogenic cystoliths.