Septic cholangitis and peritonitis in a gelding.

An 8-year-old Arabian gelding with septic cholangitis and peritonitis was successfully treated with trimethoprim/sulfadiazine. The gelding was referred for evaluation of signs of abdominal pain, icterus, fever, and weight loss. Peritoneal fluid analysis revealed septic and suppurative peritonitis. Culture of the peritoneal fluid yielded Escherichia coli and Klebsiella pneumoniae, which were sensitive to trimethoprim/sulfadiazine. On the basis of results of hepatic ultrasonography, a diagnosis of septic cholangitis also was made. The horse was treated with 30 mg of trimethoprim/sulfadiazine/kg, PO, q 12 h for approximately 6 weeks. The horse improved steadily, and telephone follow-up with the owner 1 year later disclosed that the horse had complete return to normal condition, appetite, and attitude. On the basis of our findings, aggressive, long-term anti-inflammatory and antibiotic treatment may result in complete return to health and normal athletic function in horses with septic cholangitis and concurrent septic peritonitis.