A 13 yr old female Asian small-clawed otter (Aonyx cinereal) with a six-month history of chronic kidney disease presented for bloodwork and evaluation of a mass. Anesthesia was smooth with a mildly prolonged recovery. Lab results showed static anemia and azotemia, and mild elevation in alkaline phosphatase. A 1 cm subcutaneous mass adjacent to the right caudal mammary gland was excised and tramadol was prescribed for post-operative analgesia. Over the subsequent 48 hrs the otter became lethargic, hyporexic, and polydipsic. Tramadol was discontinued due to suspicion of gastrointestinal stasis and potential sedative effects. On the fourth day post-op she was administered buprenorphine and became rapidly obtunded. The opioid was reversed and blood was collected which revealed an acute severe hepatopathy with elevations in hepatic enzymes, gamma glutamyl transferase (GGT), and bile acids. Cursory ultrasound noted an enlarged gallbladder. Recovery from anesthesia was poor and she remained unresponsive for several hours. Due to presumed hepatic encephalopathy, supportive treatment was initiated via serial applications of lactulose and neomycin per rectum which improved mentation through the night. The following morning she was taken to a local veterinary specialty hospital for diagnostic assessment of suspected biliary obstruction. Findings suggested cholecystitis with thickening of the bile duct and an emergency cholecystectomy was performed. Post-operative management included broad-spectrum antimicrobials, analgesics, gastroprotectants, prokinetics, and subcutaneous fluids. Lab results 19 days post-op showed significant improvement in clinical chemistry. The otter made a full recovery and continues medical management for chronic renal disease.
The authors wish to thank the Georgia Aquarium animal health and zoological operations staff for their commitment to excellence in animal care, Marina Ivanĉić, DVM, DACVR for her stat review of in-house ultrasound, as well as the radiology and surgical departments of Blue Pearl Sandy Springs for their assistance in the management of this case.
* Presenting author