Severe hypertriglyceridaemia in horses and ponies with endocrine disorders.

This research investigates and documents the occurrence of severe hypertriglyceridaemia, an unusually high level of triglycerides in the blood, in horses and ponies suffering from endocrine disorders. The study reviews case details from six different institutions, providing descriptions and outcomes for three horses and four ponies with this condition. These animals, while otherwise appearing healthy, experienced high triglyceride levels due to endocrine disorders related to pituitary dysfunction and insulin resistance. Treatment with medications resulted in improved laboratory results for some, but not all horses and ponies.

Methodology

• For this study, cases were identified from six different participating institutions, with data extracted from the existing medical records.
• The researchers focused on horses and ponies showing severe hypertriglyceridaemia (serum triglyceride concentration above 5.65 mmol/l) secondary to an endocrine disorder but otherwise displaying normal health.

Results

• Case details from three horses and four ponies were analyzed. Common symptoms included weight loss with a good appetite in four subjects, while the hypertriglyceridaemia condition was found incidentally in three others.
• Despite the health issues, all animals were alert, bright, and showcased normal or increased appetite. Their serum triglyceride concentrations varied broadly, ranging from 10.5 to 60.3 mmol/l.
• Additional abnormalities found included hyperglycaemia in six subjects, suspected insulin resistance, and mild to significant increases in hepatic enzyme activities. In two of these animals, moderate hepatic lipidosis was confirmed histologically.
• Based on clinical signs, ACTH concentrations, or the results of a dexamethasone suppression test, three horses and three ponies were diagnosed with pituitary pars intermedia dysfunction. Five of these animals also had type 2 diabetes mellitus, while one pony suffered from diabetes without the mentioned pituitary dysfunction.
• Following treatment with pergolide or insulin, laboratory abnormalities improved in four cases. Specific treatment was not attempted for one horse, and in two others, treatment was only partially effective or impaired by the owner. One of these cases showed persistent biochemical abnormalities for seven years without apparent ill effects.

Conclusions

• The researchers concluded that horses and ponies might develop severe hypertriglyceridaemia as a result of endocrine disorders, particularly those associated with insulin resistance.
• With treatment of these endocrine conditions, hypertriglyceridaemia can improve, even if such improvement is not systematic.
• Despite clear biochemical evidence of liver involvement, no related clinical abnormalities were noticed in the studied animals.