Clinical and pathological studies in horses with hepatic disease.

The research focused on understanding the progression of different liver diseases in horses using specific tests and diagnoses. Factors like hypokalaemia, alkalosis, and certain fatty acids and neurotransmitters were found to be potentially significant in the development of severe liver failure, known as hepatic coma.

Study Objectives and Methods

• The study aimed to follow and understand the progression of various liver diseases such as hepatic necrosis (death of liver cells), lipidosis (fatty liver), neoplasia (abnormal tissue growth), and cirrhosis (scarring of the liver) in horses. The researchers monitored this progression through serial measurements of various biological factors and liver biopsies.
• The biological factors tested include total serum bile acid concentrations and levels of plasma glutamate dehydrogenase (GD) and gamma glutamyl transferase (gamma GT). These substances are essential for liver function and their levels in the blood can indicate liver health or disease progression.
• A change in plasma ammonia concentrations and plasma urea concentration was also monitored. These are waste products that the liver normally removes from the bloodstream, so changes in their levels could indicate liver dysfunction.
• Additionally, the researchers monitored plasma glucose concentration since a decrease in this factor often indicates a poor prognosis.

Findings and Implications

• The researchers found that plasma ammonia concentrations were significantly higher in horses with liver disease than in clinically normal horses. However, these changes were not always paired with a decrease in plasma urea concentration. This suggests that increased ammonia levels alone may not be a reliable indicator of liver disease progression.
• Decreased plasma glucose concentrations were linked to a guarded (uncertain) prognosis, indicating that changes in glucose levels could be a key factor in predicting a horse’s survival chances with liver disease.
• The study also suggested that other factors like hypokalaemia (low blood potassium levels), alkalosis (an excessively alkaline state of the body fluids), short chain volatile fatty acids, and certain types of neurotransmitters might play a significant role in causing hepatic coma (a serious, life-threatening condition where the liver ceases to function) in horses with liver diseases.
• The findings of this research provide important insights into the biomarkers of liver disease progression in horses and could aid in early diagnosis and disease management. The potential role of hypokalaemia, alkalosis, fatty acids, and neurotransmitters in hepatic coma also opens up new areas for future research.