2. Lipid profile tests-Introduction
A group of tests that are often ordered together to
determine risk of coronary heart disease.
They are useful indicators of whether someone is
likely to have a heart attack or stroke caused by
blockage of blood vessels or hardening of the arteries
(atherosclerosis).
This panel of tests includes measures of;
triglycerides
Total cholesterol
Low density lipoprotein (LDL)
and high-density lipoprotein (HDL).
3. Indications- for all lipid tests
As a component of a complete examination,
especially for individuals over age 40 years or those
who are obese
To estimate the degree of risk for atherosclerotic
cardiovascular disease
Family history of hypercholesterolemia or
cardiovascular disease
Known or suspected disorders associated with
altered cholesterol levels
Monitoring of response to dietary treatment of
hypercholesterolemia
Monitoring for response to drugs known to alter
cholestrol levels
4. Total cholesterol level-
introduction
Cholesterol has two sources:
that obtained from the diet (exogenous
cholesterol)
that which is synthesized in the
body(endogenous cholesterol).
Comprises cell membrane structure
Excreted in bile as bile acids
Most is produced by the liver and the intestinal
mucosa.
5. Patient prepartion;
Patient should ingest own normal diet, for 2
weeks so that no weight gain or loss will occur for
2 weeks.
The patient should abstain from alcohol for 24
hours
Fast from food for overnight= 12 hours before the
study.
Water is not restricted.
Drugs that may alter cholesterol levels be
withheld for 12 hours before the test(although this
practice should be confirmed with the physician
ordering the study.) e.g cholestyramine,
6. procedure
A venipuncture is performed and the sample
collected in a red-topped tube. The sample
should be sent promptly to the laboratory.
7. Reference values
25 yr 125–200 mg/dL 3.27–5.20 mmol/L
25–40 yr 140–225 mg/dL 3.69–5.85 mmol/L
40–50 yr 160–245 mg/dL 4.37–6.35 mmol/L
50–65 yr 170–265 mg/dL 4.71–6.85 mmol/L
65 yr 175–265 mg/dL 4.71–6.85 mmol/L
9. Serum triglyceride levels
Are combinations of three fatty acids and one
glycerol molecule
Used in the body to provide energy for various
metabolic processes, with excess amounts stored
in adipose tissue.
Derived from
unused glucose and amino acids
adipose tissue
Diets high in calories, fats, or carbohydrates will
elevate serum triglyceride levels, which is
considered a risk factor for atherosclerotic
cardiovascular disease.
Raised in alcohol intake, hereditary
10. Reference ranges
20–40 yr
Men 10–140 mg/dL 0.11–1.58 mmol/L
Women 10–150 mg/dL 0.11–1.68 mmol/L
40–60 yr
Men 10–180 mg/dL 0.11–2.01 mmol/L
Women 10–190 mg/dL 0.11–2.21 mmol/L
11. Serum lipoproteins
Cholestrol and triglycerides are insoluble in water.
Therefore these lipids are transported in the blood as
lipoproteins—complex molecules consisting of
triglycerides, cholesterol, phospholipids, and proteins.
Are classified according to DENSITY from lowest as ;
chylomicrons,
very-low-density lipoproteins (VLDL),
low-density lipoproteins (LDL),
high-density lipoproteins (HDL).
High HDL and low LDL levels are predictive of a reduced
risk of cardiovascular disease.
High LDL cholesterol and low HDL cholesterol levels are
considered risk factors for atherosclerotic cardiovascular
disease.
12. indications
Indicated in high risk patients for cardiovascular
disease
Estimation of the degree of risk for
cardiovascular disease: increased LDL
cholesterol= high risk for cardiovascular disease
Evaluation of response to treatment for altered
levels
Support for decisions regarding the need for drug
therapy or diet modification.
Known or suspected disorders associated with
altered lipoprotein levels e.g
hyperlipoproteinaemia
13. Lipoprotein reference ranges
LDL HDL
25 yr 1.87–3.53
mmol/L
25–40 yr 2.30–4.60
mmol/L
40–50 yr 2.56–4.74
mmol/L
50–65 yr 2.69–4.96
mmol/L
65 yr 2.69–5.12
mmol/L
0.82–1.46 mmol/L
0.82–1.54 mmol/L
0.84–1.54 mmol/L
0.87–1.79 mmol/L
0.90–1.92 mmol/L
15. CARDIAC MARKERS-used
especially in myocardial infarction
ENZYMES include;
Creatinekinase enzyme(CK)/creatine
phosphokinase(CPK)
Isoenzymes include-
CK MB(heart)
CK BB(brain)
CK MM(skeletal muscle)
Aspartate aminotransferase
OTHER MARKERS(proteins);
Myoglobin
Troponin(troponin I, troponin T)
16. Indications
Indicated with a patient suspicious of having
syptoms and signs of myocardial infarction e.g
chest pain
Patient with high risk factors for myocardial
infarction e.g hypertension, diabetes, previous
history of heart attack.
Thrombolytic therapy with e.g sterptokinase is
usually the treatment for myocardial infarction
Usually multiple cardiac marker tests over time
are required for follow up .
NB; electrocardiographic studies(ECG) are used
alongside these tests to diagnose myocardial
17. CREATINE KINASE/CREATINE
PHOSPHOKINASE
Found in heart, brain and skeletal muscle
With myocardial infarction it usually the first
enzyme to rise in blood
Also increased in:
Burns,
some cancers,
bowel infarction,
Cardiomyopathy
Intramascular injections
18. Cardiac troponins
Usually do not rise immediately after myocardial
damage
However both are highly specific and sensitive for
myocardial damage
Used especially to exclude cardiac damage in
patients with chest pain therefore myocardial
infarction is most likely present with their
increase.
A venipuncture is performed and the sample is
collected in a red-topped tube.
19. Myoglobin
It is a sensitive early indicator of cardiac damage
However skeletal muscle injury can also cause its
release to blood.
It is usually used alongside cardiac enzymes.
A venipuncture is perfomed and blood collected in
a red topped vacutainer.
Increased in: myocardial infarction, others -
muscle injury ,polymyositis
20. procedure
Reassure patient
Take history of any medication used or alcohol
prior
Do not give intramascular injections as it may
interfere with test e.g creatinine kinase
Advice patient on need to repeat blood sampling
Avoid placing tourniquet for too long as it may
alter results
Venipuncture is perfomed and blood withdrawn to
a red topped vacutainer
An ECG is done if not done before
