Abstract
BACKGROUND: The pathogenesis of gallbladder (GB) mucoceles in dogs is unknown. It has been proposed that hyperlipidemia could impair GB motility and contribute to GB mucocele formation. HYPOTHESIS/OBJECTIVES: The objective of this study was to compare GB motility in dogs with hyperlipidemia to control dogs using ultrasonography. We hypothesized that hyperlipidemic dogs will have decreased GB motility compared with controls. ANIMALS: Twenty-six hyperlipidemic and 28 healthy, age-matched control dogs were prospectively enrolled. METHODS: Cholesterol and triglyceride concentrations were measured in all dogs. Hyperlipidemia was defined as hypercholesterolemia (>332 mg/dL) and/or hypertriglyceridemia (>143 mg/dL) using a biochemical analyzer. Ultrasound was performed before feeding, and 60 and 120 minutes after ingestion of a high fat diet. Gallbladder volumes (GBV) and ejection fractions (EF) were calculated. RESULTS: Hyperlipidemic dogs had significantly larger GBVs (ml/kg) before feeding and 60 minutes after feeding of 1.2 (0.4-7.5; P = .008) and 0.6 (0.1-7.2; P = .04) compared with controls 0.6 (0.2-2.6) and 0.4 (0.1-1.9), respectively. Severely hyperlipidemic dogs had significantly larger GBV at baseline, 60 minutes, and 120 minutes of 1.7 (0.6-7.5; P = .03), 1.3 (0.4-7.2; P = .02), and 1.3 (0.2-8.2; P = .04), respectively compared with mildly hyperlipidemic dogs. EFs at 60 and 120 minutes between controls, hyperlipidemic, and severely hyperlipidemic were all 0.3 at 60 minutes and 0.5, 0.3, and 0.3 at 120 minutes, respectively which were not statistically different. CONCLUSIONS AND CLINICAL IMPORTANCE: Hyperlipidemia leads to GB distention in dogs which could lead to retention of bile and gallbladder disease.