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.
Department of Population Medicine, University of Guelph, Guelph, ON, Canada. Electronic address: okaforch@gmail.com.
Chika C
CC
Okafor
Banfield Pet Hospital, 8000 NE Tillamook St, Portland, OR, USA.
Sandra L
SL
Lefebvre
Department of Population Medicine, University of Guelph, Guelph, ON, Canada.
David L
DL
Pearl
Banfield Pet Hospital, 8000 NE Tillamook St, Portland, OR, USA.
Mingyin
M
Yang
Banfield Pet Hospital, 8000 NE Tillamook St, Portland, OR, USA.
Mansen
M
Wang
Department of Clinical Studies, University of Guelph, Guelph, ON, Canada.
Shauna L
SL
Blois
Banfield Pet Hospital, 8000 NE Tillamook St, Portland, OR, USA.
Elizabeth M
EM
Lund
Department of Population Medicine, University of Guelph, Guelph, ON, Canada.
Cate E
CE
Dewey
D000367:Age Factors; D000818:Animals; D002129:Calcium Oxalate / Q000652:urine*; D016022:Case-Control Studies; D004032:Diet; D004283:Dog Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000652:urine; D004285:Dogs; D005260:Female; D006762:Hospitals, Animal; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D052878:Urolithiasis / Q000175:diagnosis / Q000453:epidemiology / Q000652:urine / Q000662:veterinary*
D002129:Calcium Oxalate
Calcium oxalate; Incidence; Lower urinary tract stones; Risk factors; Urolithiasis; Veterinary hospital