Essentials & Ethics of Clinical Laboratory Profession 0308101
Introduction to
Medical Laboratory Science
(1)
Department of Clinical Sciences
Introduction
• A laboratory is a facility that provides controlled
conditions in which scientific or technological research,
experiments, and measurement may be performed.
• A
medical laboratory or clinical laboratory is
a laboratory where tests are done on clinical specimens in
order to get information about the health of a patient as
pertaining to the diagnosis, treatment, and prevention of
disease.
What is Medical Laboratory Science?
▪ Medical laboratory science is the use of clinical
laboratory tests to detect, diagnose, monitor and treat
disease.
▪ Blood, tissue and body fluids can be chemically analyzed
and examined for foreign organisms and abnormalities.
▪ This information is then used by the medical team to
make decisions regarding a patient's medical care.
▪ 85% of all medical decisions are based on the results of
clinical laboratory testing.
What is Medical Laboratory Science?
• In additional to routine testing, duties in the clinical
laboratory include developing and modifying procedures
and monitoring programs to ensure the accuracy of test
results.
Role of medical laboratory services
The medical laboratory services play an essential
role in
1. Treating patients and monitoring their response to
treatment.
2. Monitoring the development and spread of infectious and
dangerous pathogens (disease causing organisms),
3. Deciding effective control measures against major
prevalent disease
4. Deciding health priorities.
Role of medical laboratory services
Without Reliable Laboratory Services:
▪
The source of a disease may not be identified correctly.
▪
Patients are less likely to receive the best possible care.
▪
Resistance to essential drugs may develop and continue
to spread.
▪
Epidemic diseases may not be identified on time and
with confidence.
Laboratory Tests
What are lab tests?
• Laboratory tests are medical procedures that involve
testing samples of blood, urine, or other tissues or
substances in the body.
• Many laboratory tests are readily available in the larger
laboratories, but typically only a small percentage of these
tests are routinely ordered.
• Generally, a small number of appropriately chosen
laboratory tests (a panel of tests) or a reflective testing
algorithm is sufficient to confirm or rule out one or more
of the possibilities in a differential diagnosis.
Laboratory Tests
Why does your doctor use lab tests?
Your doctor uses laboratory tests to help:
▪ Identify changes in your health condition before any
symptoms occur.
▪ Diagnose a disease or condition even before you have
symptoms
▪ Plan your treatment for a disease or condition
▪ Evaluate your response to a treatment, or
▪ Monitor the course of a disease over time
Laboratory Tests
Many factors affect test results. These include:
• Your sex, age
• What you eat and drink
• Medicines you take
• How well you followed pre-test instructions
What do lab tests show?
• Lab tests show whether your results fall within normal
ranges.
• Normal test values are usually given as a range, rather
than as a specific number, because normal values vary
from person to person.
Levels of Testing
• Clinical Laboratory Improvement Act of 1988 (CLIA ’88)
• Divides all clinical labs into:
• “Waived” Labs
• “Moderately complex” Labs
• “Highly complex” Labs
Levels of Testing
• Waived laboratories
• Lab tests can be classified as “waived” if they are simple
tests with an insignificant risk of erroneous results.
• Have no certification or education requirements for
testing personnel
• Do not require proficiency testing Examples:
• ESR,
• Glucose by glucometer
• Urinalysis by dipstick
Levels of Testing
• Moderately Complex
• Mainly manual procedures with limited steps and
preparation and automated analyses that do not require
operator intervention during the analytical process
• Requires proficiency testing.
Proficiency testing
Levels of Testing
• Highly Complex
• Designation for labs that perform ALL laboratory
testing, including highly specialized
• Requires extensive proficiency testing
Types of Laboratories
There are different types of labs
▪ Hospital laboratory
▪ Physician office labs
▪ Private (or community) laboratory
▪ Reference labs
Types of Laboratories
• A lot of samples are sent between different labs for
uncommon tests.
• It is more cost effective if a particular laboratory
specializes in a rare test, receiving specimens (and
money) from other labs, while sending away tests it
cannot do.
Types of Laboratories
Hospital laboratories
• Offer extensive testing in different specialty area,
in addition to the standard tests required to monitor the
health of the other patients in the hospital.
• Generally, hospital laboratories perform high volumes of
routine test procedures.
• Hospital laboratories may also serve as a reference
laboratory for the local community, especially for STAT
testing needs (STAT tests
are those that require
immediate results.)
Types of Laboratories
Hospital laboratories
Tests performed at a hospital laboratory may include the following:
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Electrolytes
Kidney function tests
Liver function analysis
Blood typing and crossmatches for transfusions
Identification of microorganisms and antibiotic sensitivity testing
Urine analysis
Coagulation testing
Cardiac enzyme assays
Complete blood counts (CBCs) and other hematology testing
Types of laboratories
Hospital laboratories
• Hospital laboratories may also offer another method for
testing samples, called point-of-care testing (POCT).
• Point-of-care tests are actually performed at the patient’s
bedside rather than in the laboratory, using a portable
instrument that gives immediate results.
Types of laboratories
Hospital laboratories
• These tests may be performed by laboratory personnel or
in some situations by other hospital employees who have
been trained to perform the testing.
Types of laboratories
Physician Office Laboratories (POLs)
• Are clinical laboratories within physician offices where
laboratory testing is carried out on specimens obtained
from the practices’ own patients.
• The results for tests performed on site are available quickly
and patient treatment can begin immediately if necessary.
Types of laboratories
These (outpatient) laboratories generally perform low complexity
tests which include:
• Urine analysis
• Pregnancy testing
• Coagulation testing to monitor patients who are taking
anticoagulants
• Glucose levels and other tests used to monitor diabetic patients
• Fecal occult blood tests for the presence of blood in the stool
• Cholesterol testing
• Physician office laboratories may also provide testing that is more
complex if staff members are properly trained to perform such pro
cedures.
Types of laboratories
Reference Laboratories
• Perform more tests annually than POLs or the hospital
laboratories, processing perhaps thousands of specimens
per day.
• These tests include those that are performed at hospital
laboratories, but reference laboratories may offer
specialized testing that is NOT performed at either hospital
laboratories or POLs.
• Specimens may be sent to a reference laboratory from all
over the country.
Types of laboratories
Private (or community) laboratory
• Receive samples from general physician, insurance
companies, clinical research sites and other health clinics for
analysis.
Laboratory Departments
Mainly three types of Medical Laboratories as per the
types of investigations carried out.
1. Clinical Pathology: Hematology, Histopathology, Cytology,
Routine Pathology
2. Clinical Microbiology: Bacteriology, Virology, Mycology,
Parasitology, Immunology, Serology.
3. Clinical Biochemistry: Biochemical analysis, Hormonal
assays etc.
Laboratory Departments
Laboratory Departments
These departments may include the following:
• Phlebotomy (blood collection)
• Specimen Processing: The area of the laboratory where
all incoming specimens are
• Sorted,
• Accessioned into the computer system of the laboratory,
• Appropriately labeled for transport to their respective
departments for testing.
• The specimen processing department may also prepare
specimens for transport to reference laboratories.
Laboratory Departments
• Hematology: Whole blood testing, which focuses on the
formed elements (the blood cells) in the blood.
• Coagulation testing is also performed in this department.
Laboratory Departments
• Clinical Chemistry: Testing performed on plasma or
serum and includes analysis of the substances dissolved in
the blood- stream.
• Most testing is automated, and many of the tests are
performed as panels or groups of tests.
Laboratory Departments
• Serology/Immunohematology: Testing that focuses
primarily on the presence of antigens or antibodies on
cells or in the liquid portion of the blood.
• Blood typing and antibody screens and crossmatches for
transfusions may also be performed in this department.
Laboratory Departments
• Urinalysis: The physical appearance of urine is assessed,
and urine chemical and microscopic analysis is performed.
Laboratory Departments
• Microbiology/Parasitology: Identification of pathogenic
microorganisms and antibiotic sensitivity testing.
Laboratory Departments
• Cytology:
• Examination of various specimens for abnormal cells,
chromosomal studies, Pap smears.
Laboratory Departments
• Coagulation:
• Specimens testing for the presence of various clotting
factors.
Laboratory Departments
• Blood Bank
• Perform crossmatch to identify compatible blood for
patients who are bleeding or for surgery.
• Some people have unusual blood types, and a detailed
evaluation must be performed.
Laboratory Departments
• Histology/Pathology: Tissue samples examined for
abnormal function and form.
Laboratory Departments
Laboratory Departments