Clinical Laboratory Test of Lipoprotein Panel

CLINICAL LABORATORY TEST OF LIPOPROTEIN PANEL

Include cholesterol, low density lipoprotein (LDL) cholesterol, trigliserides, and hight density lipoprotein (HDL) cholesterol.

CHOLESTEROL

Normal Values :
Desirable : 0 – 199 mg/dL [SI = 0-5.17 mmol/L]
Borderline : 200 – 239 mg/dL [SI = 5.2-6.21 mmol/L]
High Risk : ≥ 240 mg/dL [SI = ≥6.22 mmol/L]

Description :
Cholesterol exists in muscle, RBCs, and cell membranes. It is used by the body to form steroid hormones, bile acids, and cell membranes. Elevated cholesterol concentrations are associated with atherosclerosis and an increased risk of coronary artery disease.

Clinical Implication :
1.Increased levels of > 200 mg/dL are considered to be high and require a triglyceride evaluation. Associated conditions include cardiovascular disease, atherosclerosis, Type II familial hypercholesterolemia, and obstructive jaundice.
2.Decreased levels are associated with malabsorption, liver disease, sepsis, and pernicious anemia.
3.A patient must fast for 12 hours before blood is obtained to measure the serum concentration of cholesterol, and should maintain a “normal” diet for 7 days prior. Alcohol should not be consumed 24 hours before testing and all lipid-lowering drugs should be withheld.

LOW DENSITY LIPOPROTEINS (LDL)

Normal Values (Adult) :
Desirable : < 130 mg/dL [SI = <3 data-blogger-escaped-.36="" data-blogger-escaped-br="" data-blogger-escaped-mmol="">Borderline : 130-159 mg/dL [SI = 3.36-3.11 mmol/L]
High Risk : ≥ 160 mg/dL [SI = >4.13 mmol/L]

Description :
LDL are beta cholesterol esters

clinical Implication :
High LDL values are associated with coronary vascular disease or familial hyperlipidemia. Levels may also be elevated samples taken from non fasting subjects. Levels may also be elevated in types IIa and IIb hyperliproteinemia, diabetes mellitus, hypothyroidism, obstructive jaundice, nephrotic syndrome, familial and idiopathic hyperlipidemia, and with the use of estrogens or estrogens-containing oral contraceptives.
Decreased LDL levels may occur in patients with hypoproteinemia.

HIGH DENSITY LIPOPROTEINS (HDL)

Normal Values : Adult : 30-70 mg/dL [SI = 0.78-1.18 mmol/L]
Description : HDL are the products of liver and intestinal synthesis and triglyceride catabolism.

Clinical Implication :

1. There is an inverse relationship between HDL-cholesterol levels and the incidence of coronary artery disease.
2. Increased HDL cam occur in chronic alcoholism, primary biliary cirrhosis, and subsequent to exposure to industrial toxins or polychlorinated hydrocarbons. Patients taking clofibrate, estrogens, nicotinic acids, oral contraceptives, and phenytoin may have increased HDL levels.
3. Decreased HDL can occur in patients with cystic fibrosis, severe hepatic cirrhosis, diabetes mellitus, Hodgkin’s disease, nephritic syndrome, malaria, and some acute infections. Patients receiving probucal, hydrochlorothiazide, progestins, and prolonged parenteral nutrition may have decresed HDL levels.

TRIGLYCERIDES

Normal Values (desirable adult) :
Male : 40-160 mg/dL [SI = 0.44-1.88 mmol/L]
Female : 35-135 mg/dL [SI = 0.4-1.53 mmol/L]
Description :
Triglycerides are found in plasma lipids are chylomicrons and very low density lipoproteins (VLDL)

Clinical Implications :

1. Triglycerides are increased in patients with alcoholic cirrhosis, alcoholism, anorexia nervosa, biliary cirrhosis, biliary obstruction, cerebral thrombosis, chronic renal failure, diabetes mellitus, Down’s syndrome, hypertension, idiopathic hypercalcemia, hyperlipoproteinemia (type I, IIb, III, IV and V), gout, ischemic heart disease, hypothyroidism, pregnancy, acute intermittent porphyria, respiratory distress syndrome, thalassemia major, viral hepatitis, and Werner’s syndrome.
2. Cholestyramine, corticosteroids, estrogens, ethanol, high carbohydrate diets, intravenous miconazole, oral contraceptives, and spironolactone can increase triglycerides.
3. Decreased triglycerides may be seen with chronic obstructive lung disease, hyperparathyroidism, intestinal lymphangiectasia, severe parenchymal liver disease, malabsorption, and malnutrition.
4. Ascorbic acid, asparaginase, clofibrate, and heparin can decrease triglyceride serum concentrations.

Source : Boh, L.E. 1996. Clinical Clerkship Manual. Applied Threpuetics, Inc. Washington, 5-33, 5-34, 5-36