Medical treatment of cholangiohepatitis and cholelithiasis in mature horses: 9 cases (1991-1998).

The study explores the treatment of cholangiohepatitis and cholelithiasis in horses using medical therapies, indicating that seven of nine horses treated responded well and returned to normal functioning. Long-term antibiotic therapy was shown to be crucial for the overall recovery.

Objective and Approach

• The study aims to discuss and review the treatment of cholangiohepatitis and cholelithiasis – liver conditions associated with inflammation of the bile ducts and liver stones respectively – in horses.
• The research primarily focuses on a medical approach to treating these conditions, involving long-term use of antimicrobials.
• Nine horses were studied over a period spanning from 1991 to 1998, and their responses to the treatment were recorded and analyzed.

Findings and Observations

• Seven out of the nine horses successfully responded to the treatment and were able to return to their normal activities, with a minimum follow-up period of a year.
• A median treatment duration of 51 days was recorded, ranging from 17 to 124 days, further emphasizing the need for long-term antimicrobial therapy for the horses to survive.
• Fatal response to the treatment was related to severe liver conditions, including severe periportal and bridging hepatic fibrosis and hyperammonaemic hepatic encephalopathy.
• All subjects showed signs of suppurative cholangiohepatitis, with varying degrees of periportal and bridging fibrosis.

Diagnostic and Treatment Techniques

• The researchers used a transabdominal ultrasound for diagnosis in each horse, helping them obtain liver tissue for lab examination and bacterial culture, assess liver size and echogenicity, and monitor the dissolution of hepatoliths.
• Discrete hyperechoic calculi were identified in four cases, but all horses exhibited ultrasonographic evidence of biliary obstruction, indicated by several dilated bile ducts.
• In two horses, different species of Escherichia coli, and Bacteroides vulgatus were detected.
• In successful cases, physical recovery was observed first, even before the normalization of biochemical indices of liver and bile duct function, which included gammaglutamyl transaminopeptidase (GGT), alkaline phosphatase (AP), bile acids, and serum bilirubin.
• The GGT levels were consistently monitored as an indicator of liver and biliary disease. These levels were observed to initially rise even as the horses displayed clinical signs of improvement.

Recommendations and Conclusion

• The authors emphasize that supportive medical therapies, such as intravenous fluids, were essential aspects of the treatment procedure. They were used throughout treatment, especially for chronic cases that worsened during the treatment period.
• The research stresses the importance of continuing the treatment until the GGT levels return to normal. This recommendation comes from the observation that past treatment failures might have resulted from insufficient treatment durations.