Percutaneous Ultrasound‐guided Cholecystocentesis and Bile Analysis for the Detection of Platynosomum spp.‐Induced Cholangitis in Cats

BACKGROUND: Examination of bile could be useful to diagnose Platynosomum spp.‐induced cholangitis in cats. Obtaining bile via percutaneous ultrasound‐guided cholecystocentesis (PUC) is possible but raises safety concerns in cats with severe cholecystitis. OBJECTIVES: The objectives of this study were to investigate the use of PUC to collect bile samples from cats with known platynosomosis and to determine if bile analysis could be a diagnostic test. ANIMALS: Twenty‐seven free‐roaming cats positive for Platynosomum spp. eggs via fecal examination. METHODS: In this prospective study, fecal egg counts were performed by double centrifugation with Sheather's solution. Bile was collected using PUC from anesthetized cats. Egg counts in bile were performed with a stereoscope. Euthanasia and postmortem examination were performed immediately after PUC. RESULTS: All cats had ultrasound (US) evidence of cholangitis or cholecystitis. Thirty‐nine PUCs were performed with 14 cats having 2 PUCs 12 or 24 days apart. Postmortem examinations showed no overt gallbladder damage or leakage but fresh blood was noted in the gallbladder lumen of 3 cats. Median Platynosomum spp. egg counts were higher in bile (1450 eggs/mL; IQR, 400; 5138 eggs/mL) as compared to feces (46 eggs/mL; IQR, 10; 107 eggs/mL) (P < .001). CONCLUSION AND CLINICAL IMPORTANCE: Bile egg count analysis is an alternative method with higher egg counts as compared to fecal egg count analysis for the diagnosis of platynosomosis. Obtaining bile via US guidance is technically feasible and safe in cats with cholangitis/cholecystitis. Cholecystocentesis and bile analysis are especially relevant for those cats with chronic cholangitis/cholecystitis and negative fecal egg counts for Platynosomum.