Spontaneous Course of Biliary Sludge Over 12 Months in Dogs with Ultrasonographically Identified Biliary Sludge

J Vet Intern Med. 2016 May;30(3):771-8. doi: 10.1111/jvim.13929. Epub 2016 Mar 16.

Abstract

Background: Biliary sludge is associated with gallbladder (GB) dysmotility and mucus hypersecretion suggesting a link between biliary sludge and the formation of GB mucoceles (GBM). If biliary sludge progresses to GBM, treatment to reduce the production and progression of sludge is warranted.

Hypothesis/objectives: The objective of this study was to determine the course of biliary sludge in dogs.

Animals: Seventy-seven healthy, client-owned dogs ≥4 years of age screened for biliary sludge; 45 affected dogs identified.

Methods: Prospective, observational design. Serial ultrasound examinations were evaluated at 3, 6, 9, and 12 months to monitor degree of sludge based on proportion of GB filled with sludge (mild [0.01-24.4%], moderate [24.5-49.4%], moderate to severe [49.5-74.4%], severe [74.5-100%]), gravity dependency of sludge, and GB dimensions.

Results: After 1 year of follow-up, the degree of sludge was mild (34%), moderate (47%), moderate to severe (13%), severe (3%), or absent (3%). There was no significant difference in median degree of sludge over 1 year (P = .36). There were no significant changes in the gravity dependency of sludge over 1 year. A subset of dogs, 24%, with initial gravity-dependent sludge developed a combination of nondependent and dependent sludge. Dogs had resolved (2%), decreased (19%), static (40%), increased (29%), or recurrent (10%) sludge at the conclusion of the study.

Conclusions and clinical importance: Biliary sludge was prevalent, affected dogs remained asymptomatic, and it rarely resolves in healthy dogs over a period of 1 year. Some dogs developed nongravity-dependent sludge within 1 year, which might indicate changes in consistency of sludge.

Keywords: Gallbladder; Microlithiasis; Mucocele; Ultrasonography.

Publication types

  • Observational Study

MeSH terms

  • Animals
  • Bile / chemistry
  • Bile / diagnostic imaging*
  • Bile / physiology
  • Dog Diseases / diagnostic imaging
  • Dog Diseases / pathology*
  • Dogs
  • Female
  • Gallbladder Diseases / diagnostic imaging
  • Gallbladder Diseases / pathology
  • Gallbladder Diseases / veterinary*
  • Male
  • Ultrasonography / veterinary