In this disorder there is an excess of fats and fat-like substances (lipoproteins) in the blood, resulting from a defect in lipoprotein metabolism. The two clinically important lipids in dogs are cholesterol and triglycerides. There are similarities to familial hypertriglyceridemia in people.
The mode of inheritance is unknown.
An elevation of triglycerides (hypertriglyceridemia) usually causes periodic episodes of vomiting and diarrhea with abdominal discomfort and lack of appetite. These signs last for a few hours or days and may resolve on their own while your dog doesn't eat.
Sustained high blood levels of glycerides are also associated with an increased risk for pancreatitis, a life-threatening disease which causes profuse vomiting and severe abdominal pain.
Elevated blood cholesterol levels on their own do not appear to cause any problems.
Your veterinarian will likely suspect this condition based on clinical signs (described above) together with a fatty (lipemic) blood sample. Although it is not uncommon for any dog to have fat in a blood sample shortly after a meal, a sample that is lipemic after 12 hours of fasting is diagnostic for high blood levels of triglycerides.
Sometimes hypertriglyceridemia only becomes apparent when your veterinarian takes a blood sample from your dog for an unrelated reason.
Hypercholesteremia on its own doesn't cause clinical signs, but may be found incidentally on a blood sample.
Restriction of dietary fat is the most important therapy for hypertriglyceridemia. Once a diet has been established that will keep the level of triglycerides in the blood below a certain level, your dog will need to stick to the diet for life. Your veterinarian will monitor the levels of triglycerides annually or if there is an unexplained episode of vomiting and diarrhea.
It is important for you or anyone caring for your dog to be aware of the risks of consuming a large amount of fat in a single meal ( eg. garbage) which can bring on a fatal episode of pancreatitis.
Due to the risks associated with sustained high blood levels of triglycerides, even dogs without clinical problems at the time of diagnosis should undergo dietary management to restrict fat.
Treatment is not required for hypercholesteremia.
For the veterinarian: The goal is to achieve, with dietary management, a serum TG (in uncleared serum) of 500 mg/dl and a normal CH, with little or no weight loss. There are some drug therapies that have been tried but the benefits have not been substantiated.
Normal post-prandial dogs may have a transient (6 - 10 hours), modest (150 - 400 mg/dl) elevation of serum triglycerides. A grossly lipemic fasting serum sample is diagnostic for hypertriglyceridemia. Hypercholesterolemia can only be detected by laboratory examination.
Hyperlipidemia is clinically important when fasting triglyceride concentrations exceed 500 mg/dl or cholesterol exceeds 300 mg/dl. It is important that the values be measured on uncleared serum samples.
FOR MORE INFORMATION ABOUT THIS DISORDER, PLEASE SEE YOUR VETERINARIAN.
Ford, R.B. 1995. Canine hyperlipidemia. in S.J. Ettinger and E.C. Feldman (eds.) Textbook of Veterinary Internal Medicine, pp.1414-1419. W.B. Saunders, Toronto.