Cholelithiasis in the Dog: Prevalence, Clinical Presentation, and Outcome

Abstract

Canine cholelithiasis is considered to be an uncommon condition and is frequently cited as being an incidental finding. However, there is a paucity of contemporary literature to support these assertions. The aim of this retrospective cross-sectional study was to report the prevalence, clinical presentation, and long-term follow-up of cholelithiasis in dogs. The electronic database at the Small Animal Hospital, University of Glasgow was searched to identify dogs that were diagnosed with cholelithiasis on ultrasound between 2010 and 2018. Sixty-eight dogs were identified, giving an overall prevalence of cholelithiasis in our hospital of 0.97% (confidence interval 0.76–1.22%). Medical records of 61 dogs were available for review. Cholelithiasis was classified as an incidental finding in 53 (86.9%) dogs, with 8 (13.1%) dogs being classified as symptomatic, having complications of cholelithiasis that included biliary duct obstruction, biliary peritonitis, emphysematous cholecystitis, and acute cholecystitis. Follow-up was available for 39 dogs, with only 3 dogs (7.7%) developing complications attributed to cholelithiasis, including biliary duct obstruction and acute cholecystitis, within the subsequent 2 yr. Cholelithiasis is an uncommon but frequently incidental finding in dogs. Within the follow-up period, few of the dogs with incidental cholelithiasis went on to be become symptomatic.

Clinical features and outcomes in 38 dogs with cholelithiasis receiving conservative or surgical management

“…Age therefore should be considered when assessing dogs with cholelithiasis because younger dogs in our study appeared more likely to have symptomatic cholelithiasis. Almost 50% of dogs in our study were considered symptomatic, contrasting with previously published findings of just 13.1% 1 . In the human and veterinary medical literature, most cases of cholelithiasis are reported to be incidental, 1,2,6,11,16,17 with clinical signs often seen with concurrent cholecystitis, associated with biliary obstruction or gallbladder rupture 3,5 .…”

“…Similar to previous reports, older, small‐breed dogs were overrepresented in our study with a high prevalence in CKCS 2,4,14 . We did not identify a significant sex predisposition, similar to a previous study 1 . These findings contrast with those in the human medical literature where females have a higher incidence of cholelithiasis, suspected to be associated with the effects of estrogen to enhance cholesterol synthesis and decrease bile acid synthesis 11,15‐19 .…”

“…Previous reports of medical management of cholelithiasis in dogs have documented persistence of cholelithiasis despite clinical improvement 1‐3,6 . In contrast to choleliths in humans, which are primarily cholesterol‐based, choleliths in dogs usually are composed of calcium carbonate, cholesterol, and bilirubin 4 .…”

“…Cases were classified as incidental when their clinical signs were not attributable to cholelithiasis, with ultrasonographic evidence of an otherwise normal biliary tract and no biochemical abnormalities attributable to cholelithiasis, or when clinical signs and biochemical abnormalities could be attributed to another disease process. Criteria were modeled on a recent study of cholelithiasis in dogs 1 …”

“…Cholelithiasis is an uncommon condition in dogs, with a recent study identifying a prevalence of 0.97% 1 . Geriatric, female, small breed dogs are overrepresented in studies of cholelithiasis in dogs 2‐4 .…”