Concentration of lipid in the blood of a fasted (>12 h) patient that exceeds the upper range of
normal for that species; includes both hypercholesterolemia and hypertriglyceridemia
Lipemic serum or plasma separated from blood that contains an excess concentration of
Lactescence opaque, milklike appearance of serum or plasma that contains an even higher
concentration of triglycerides (>1000 mg/dL) than lipemic serum
PATHOPHYSIOLOGY Primary Hyperlipidemia
Idiopathic hyperchylomicronemia defect in lipid metabolism causing hypertriglyceridemia and
hyperchylomicronemia; possibly caused by a defect in lipoprotein lipase activity or the absence of the surface apoprotein CII; familial disorder in the miniature schnauzer
Hyperchylomicronemia in cats familial, autosomal recessive defect in lipoprotein lipase activity Idiopathic hypercholesterolemia occurs in some families of Doberman pinschers and Rottweilers;
Postprandial absorption of chylomicrons from the gastrointestinal tract occurs 30–60 min after
ingestion of a meal containing fat; may increase serum triglycerides for 3–10 hours
Diabetes mellitus low lipoprotein lipase (LPL) activity; high synthesis of very-low-density
Hypothyroidism low LPL activity and lipolytic activity by other hormones (e.g., catecholamines);
reduced hepatic degradation of cholesterol to bile acids
Hyperadrenocorticism increased synthesis of VLDL by the liver and low LPL activity causes both
hypercholesterolemia and hypertriglyceridemia.
Liver disease hypercholesterolemia caused by reduced excretion of cholesterol in the bile Nephrotic syndrome common synthetic pathway for albumin and cholesterol and possibly low
oncotic pressure lead to increased cholesterol synthesis.
Obesity excessive hepatic synthesis of VLDL
Ophthalmic Nervous Endocrine/Metabolism Gastrointestinal Hepatobiliary
Dog and cat Variable, depending on the cause Hereditary hyperlipidemias age of onset is >8 months in cats and >4 years in predisposed breeds
Recent ingestion of a meal Seizures Abdominal pain and distress Neuropathies
Physical Examination Findings
Lipemia retinalis Lipemic aqueous Neuropathy Cutaneous xanthomata Lipid granulomas in abdominal organs
Increased Absorption of Triglycerides or Cholesterol Increased Production of Triglycerides or Cholesterol
Nephrotic syndrome Pregnancy Defects in lipid clearance enzymes or lipid carrier proteins Idiopathic hyperchylomicronemia Hyperchylomicronemia in cats Idiopathic hypercholesterolemia
Decreased Clearance of Triglycerides or Cholesterol
Hypothyroidism Hyperadrenocorticism Diabetes mellitus Pancreatitis Cholestasis
Obesity High dietary intake of fats Genetic predisposition in miniature schnauzer and Himalayan cat Idiopathic hypercholesterolemia observed in families of Doberman pinschers and rottweilers
Diagnosis DIFFERENTIAL DIAGNOSIS Fasting Hyperlipidemia
Rule out postprandial lipemia with a 12-hour fast.
Idiopathic hyperchylomicronemia is observed most commonly in the miniature schnauzer breed. Hyperchylomicronemia in cats often manifests as polyneuropathies and lipogranulomas. Idiopathic hypercholesterolemia is observed most frequently in the Doberman pinscher and
rottweiler breeds; animals are often asymptomatic.
Diabetes mellitus signs include polyphagia, weight loss, polydypsia, and polyuria; glycosuria and
fasting hyperglycemia confirm the diagnosis.
Hypothyroidism signs include lethargy, hypothermia, heat seeking, and dermatologic changes
Pancreatitis signs include abdominal pain, vomiting, diarrhea, and anorexia; often hyperlipidemia
is accompanied by high liver enzyme activities and high lipase and amylase.
Hyperadrenocorticism signs include polydypsia, polyuria, polyphagia, dermatologic changes (e.g.,
alopecia and thin skin), and hepatomegaly; hypercholesterolemia often is attended by high ALP isoenzyme.
Hepatic disease and cholestatic disorders—signs include anorexia, weight loss, and icterus. Nephrotic syndrome signs include ascites and peripheral edema; hypercholesterolemia is observed
in conjunction with hypoproteinemia and proteinuria.
LABORATORY FINDINGS Sample Handling
Submit serum. Lipemia causes hemolysis if serum remains on RBC for a long time; inquire about the laboratory
method of clearing lipemic samples before submission.
Two samples may be submitted: one for biochemical analysis, which may be cleared, and one for
triglycerides and cholesterol concentrations.
Drugs That May Alter Laboratory Results
Corticosteroids Phenytoin Prochlorperazine Thiazides Phenothiazines
Disorders That May Alter Laboratory Results
Nonfasted samples (<12 hours) Icterus spectrophotometric techniques Fluoride and oxalate anticoagulants enzymatic techniques Lipemia
Valid If Run in Human Laboratory? CBC/BIOCHEMISTRY/URINALYSIS
Results of hemogram usually normal Hyperadrenocorticism polycythemia and nucleated RBCs Hypothyroidism mild normocytic, normochromic anemia High triglycerides dogs, >150 mg/dL; cats, >100 mg/dL High cholesterol dogs, >300 mg/dL; cats, >200 mg/dL Nephrotic syndrome low albumin Diabetes mellitus high serum glucose Hyperadrenocorticism high ALP activity Pancreatitis high serum lipase Results of urinalysis often normal Nephrotic syndrome—proteinuria
OTHER LABORATORY TESTS
HDL and LDL determinations used in human medicine; values reported for HDL and LDL in
dogs and cats cannot be assumed to be reliable.
Chylomicron test obtain serum sample after a 12-hour fast and refrigerate for 12–14 hours; do not
freeze; chylomicrons rise to the surface and form a creamy layer.
Lipoprotein electrophoresis separates LDL, VLDL, HDL1, and HDL2 LPL activity collect serum for triglycerides and cholesterol concentrations and lipoprotein
electrophoresis before and 15 min after IV administration of heparin (90 IU/kg); if there is no change in values before and after heparin administration, a defective LPL enzyme system should be suspected.
T and T determinations indicated if hypothyroidism is suspected
Adrenocorticotropic hormone (ACTH) stimulation test indicated if hyperadrenocorticism is
DIAGNOSTIC PROCEDURES Treatment
Diet should contain <10% fat (e.g., Hill's r/d, Iams restricted calorie).
Medications DRUG(S) OF CHOICE
Initial management is dietary. See Alternative Drugs if diet fails to control hyperlipidemia.
CONTRAINDICATIONS PRECAUTIONS POSSIBLE INTERACTIONS ALTERNATIVE DRUG(S)
Gemfibrozil 7.5 mg/kg PO q12h Fish oils linolenic acid (omega-3 polyunsaturated fat), 10–30 mg/kg PO q24h Clofibrate and niacin not currently recommended in cats or dogs
Follow-Up PATIENT MONITORING
Keep triglyceride concentrations < 500 mg/dL to avoid possibly fatal episodes of acute
Checking cholesterol often is not necessary because hypercholesterolemia is not associated with
Pancreatitis and seizures are common complications of hyperlipidemia in the miniature schnauzer. In cats with hereditary chylomicronemia, xanthoma formation, lipemia retinalis, and neuropathies
have been reported; peripheral neuropathies usually resolve 2–3 months after institution of a low-fat diet.
Miscellaneous ASSOCIATED CONDITIONS
Pancreatitis Seizures Neuropathies
AGE-RELATED FACTORS ZOONOTIC POTENTIAL PREGNANCY SYNONYMS ABBREVIATIONS
ALP = alkaline phosphatase HDL = high-density lipoprotein LDL = low-density lipoprotein LPL = lipoprotein lipase T = thyroxine
Barrie J, Watson TOG. Hyperlipidemia. In: Bonagura JD, ed. Kirk's Current veterinary therapy
XII. Philadelphia: Saunders, 1995:430–434.
Ford R. Canine hyperlipidemias. In: Ettinger ST, Feldman EC, eds. Textbook of veterinary
internal medicine. 4th ed. Philadelphia: Saunders, 1994:1414–1418.
Jones B. Feline hyperlipidemias. In: Ettinger ST, Feldman EC, eds. Textbook of veterinary
internal medicine. 4th ed. Philadelphia: Saunders, 1994:1410–1413.
Author: Deborah S. Greco Consulting Editor: Editor Deborah S. Greco
Publicación de la Unión de Escritores y Artistas de CubaAño 2, números 6 - 7. La Habana, enero, 2008Con una conferencia del doctor Eusebio Leal, Historiador de la Ciudad de La Habana, se iniciaron en la UnEAC los actos por el 50 aniversario del triunfo de la Revolución. Para celebrar ese importante acontecimiento, la Asociación de Escritores convocó el ciclo La Revolución, la escri-