Gallbladder sludge in cats: associations with bile culture, liver enzymes and cholangiohepatitis in 166 cases

Abstract

Objectives: To determine the clinical relevance of gallbladder sludge (GBS) in cats by assessing its association with neutrophilic cholangitis/cholangiohepatitis (NC/CH), bile culture results, serum biochemical abnormalities and ultrasonographic findings suggestive of pancreatitis or small intestinal thickening. Methods: A retrospective review was performed on 166 cats that underwent percutaneous ultrasound-guided cholecystocentesis. Data collected included ultrasonographic presence of GBS, bile culture and cytology results, liver enzyme activities, total bilirubin concentration and final diagnosis of NC/CH. Statistical associations were evaluated using Fisher’s exact test and odds ratios (ORs). Results: GBS was identified in 107/166 (64%) cats. There was no significant association between GBS and positive bile culture, bactibilia or NC/CH (P >0.84), nor with elevated alkaline phosphatase activity or total bilirubin (P >0.8). Cats with GBS were more likely to have normal alanine aminotransferase (ALT) activity compared with GBS-negative cats (OR 0.42; P = 0.025). Among GBS-positive cats, the presence of concurrent pancreatitis or intestinal thickening did not significantly increase the likelihood of NC/CH. A non-significant association was observed between elevated ALT activity and NC/CH in GBS-positive cats (OR 2.53; P = 0.135). Conclusions and relevance: GBS is a frequent ultrasonographic finding in cats but does not reliably predict biliary infection or inflammation. These findings suggest that GBS should not be used in isolation to guide antimicrobial therapy or bile sampling. Clinical judgment and supporting diagnostic data remain essential in evaluating suspected hepatobiliary disease.