2. Ms. Tiffany was offered a position of
Executive Officer in a public enterprise.
One of the requirements for confirming
her position was a Certificate of Medical
Fitness. She visited her doctor and was
told that she would do some Chemical
Pathology laboratory investigations. The
doctor filled out a laboratory form
requesting for fasting blood glucose, lipid
profile, liver, thyroid, adrenal and renal
function tests, urine analysis and a
screen test for HIV. She was puzzled, as
she did not understand the meanings of
these medical terms. She , however,
went to the laboratory department of the
Eric Williams Medical Sciences Complex
and inquired as to the type of biological
specimens required for the tests.
Unfamiliar terms
Chemical pathology- the study of the biochemical
basis of disease and the application of biochemical
and molecular techniques in diagnosis.
Fasting blood glucose- a check of a person’s blood
glucose level after the person has not eaten for 8-12
hours.
Lipid profile- a group of tests that measures the
levels of cholesterol and triglycerides and is used to
assess the risk of developing cardiovascular disease
and monitor treatment.
Liver function test- common tests that are used to
determine how well the liver is working e.g. ALP,
albumin, urine and bilirubin.
Thyroid function tests- test used to determine how
well the thyroid produces its hormones; levels of
TSH, T3, T4 and TGB can be used.
Renal function test- test used to determine the
kidney’s efficiency.
Urine analysis (urinalysis)- analysis of the urine by
physical, chemical and microscopic means to test
for the presence of disease, drugs and other
substances.
2
3. • Discuss what comprises the Certificate of Medical
Fitness.
• Discuss the chemical pathology laboratory tests; their
ranges and uses.
• Discuss the type of biological specimens needed for the
tests.
• Discuss quantitative and qualitative tests.
• Discuss the difference between diagnostic and screen
tests.
• Discuss the factors that affect the interpretation and
chemical pathology results (age, time of sample
collection, gender and diurnal variation).
• Discuss important items of information required on a
laboratory request form. 3
4. • This is a pre-requisite for certain employment.
• It is important;
-to ensure that the job candidate is healthy and can perform the duties that are
required of them on the job
-to initiate a record on the employee, this can be useful in the case of health
emergencies
-for insurance purposes
-for determining the nature of a condition that may affect safety and efficiency
of the applicant
-to ensure that employees are treated fairly (in the case of a disabled person
provisions such as brailed document , for example, can be supplied)
-to adjudicate claims of discrimination under the Rehabilitation Act of 1973, as
amended
• Each certificate of medical fitness is tailored to meet the requirements of the
company or institution to which an applicant applies.
4
9. • Bodily fluids such as blood, urine, CSF,
plural fluid, synovial fluid and ascetic fluid
are tested
• Urine is ideally collected first but in
practice blood is the first fluid collected
from patient
• Determines the condition of the body by
comparing the tested values with
standard values
• Used for diagnosis (investigation that
indicates a particular metabolic
condition), prognosis (information in
given about the course of a disease),
screening (presence of a disease that
may not have clinical manifestation) and
treatment of illness.
9
11. Diagnostic tests
• Diagnostic tests can be performed at any time, as long as there are symptoms
and/or signs that suggest to your primary care provider that a condition or
disease may be present and a test is needed to confirm the diagnosis.
Screening tests
• Screening tests are recommended for people who don’t show symptoms and/or
signs of a condition or disease, but may be at an increased risk based on their
age, gender or other factors. Some common screening tests include Pap smears
for women and colonoscopies for people age 50 and older.
• Screening tests are preventive services that serve to detect disease in its early
stages. Early detection generally offers the best opportunity for successful
treatment.
11
12. • Urine is collected via the midstream clean catch method
12
15. • Blood samples are collected into tubes by a
phlebotomist. The tubes have different coloured tops to
represent the type of test to perform on the sample.
Figure 12: Blood Collection into Tubes with Identifying Color Tops 15
20. • correct identification of the patient
• appropriate preparation of the patient where necessary
• collection of the specimen into an appropriate container with the
correct anticoagulant or preservative
• accurate labelling of the specimen container after the sample has
been collected (not before, as this carries a higher risk of a specimen
being put into a container bearing another patient’s name). Primary
labelling of the sample with a barcode at source reduces the risk of
mislabelling in the laboratory
• rapid and secure transport to the laboratory. Some specimens need
to be transported under special conditions, for example arterial blood
for ‘blood gases’ in a sealed syringe in an ice-water mixture; requests
for blood, urine or faecal porphyrins must be protected from light.
20
29. • Hussein N S, Sadiq S M, Kamaliah M D, NorAkmal A W,
Gohar M N. Twenty-four-hour urine constituents in stone
formers: A study from the northeast part of Peninsular
Malaysia. Saudi J Kidney Dis Transpl 2013;24:630-7
• http://www.hmsa.com/help-center/screening-and-diagnostic-tests/
• https://www.inkling.com/read/marshall-clinical-biochemistry-
3rd/chapter-2/factors-affecting-test-results
• http://emedicine.medscape.com/article/773832-overview
• Raffick A.R. Bowen, Alan T. Remaley2. Interferences from
blood collection tube components on clinical chemistry assays.
Biochemia Medica 2014;24(1):31-44.
http://dx.doi.org/10.11613/BM.2014.006
• Wikipedia
29
