DEFINITION
Laboratory medicine a specialty in which pathologists provide testing of patient samples (usually blood or urine) in several different areas.
Determination of the level of enzymes in blood in case of heart attack or
Level of glucose (sugar) in the blood of a patient with diabetes.
The presence of bacteria and other microorganisms.
Blood cells studies for various types of anemias
COURSE CONTENTS Clinical Biochemistry
Cardiac profilesLiver and renal panelsBone metabolismLipid chemistry
Special chemistryCardiovascular markersTumour markersNutritional markersCalculi
Immunology and ImmunodiagnosticsDrug monitoringUrine and serum proteinsAutoimmune disease testingEndocrinology testsFertility testing
Point-of-Care TestingCardiac markersGlucose monitoring programBlood gases and metabolitesRoutine chemistry panelsRoutine urinalysis and pregnancy screeningCoagulationComplete Blood Counts Urine toxicology screening
Laboratory Hematology Routine and special hematology
Hemoglobinopathy studiesSpecial stains
HematopathologyBone marrow consultations and
interpretive report Special coagulation
Coagulation profiles, screening and factors and inhibitors
Platelet studiesThrombophilia testing
Microbiology Infection control
Reference centre for medical microbiology and infectious diseases
Detection and typing of epidemiologically significant organisms
Molecular Diagnostic Testing Blood Bank/Donor Center
Concepts of immunohematology and histocompatibility
Blood transfusion services and quality assurance
Blood donation and storage of bloodBlood groupingCompatibility testing
RECOMMENDED BOOKS
Textbook:Clinical biochemistry an illustrated color
atlas by Allan GawDistrict laboratory practice in tropical
countries by Monica Cheesbrough.Clinical chemistry by William J Marshall.
Reference books:
Medical Laboratory technology by Ramnik Sood.
REASONS FOR ORDERING TESTS
Confirm diagnosis
Aid in diagnosis
Evaluate prognosis
Monitor therapy
Screen for a disease
SECTIONS OF THE LABORATORY CLINICAL PATHOLOGY
1. Clinical Chemistry Liver profile Lipid profile Glucose profile
Special chemistry(endocrinology, fertility)
2.Clinical Microscopy Analysis of body fluids Urin analysis Fecal anaysis Semen analysis
3. Microbiology Cultures (sputum,blood, urine) Sensitivity tests4. Hematology Biggest section Includes CBC,coagulation,
PT, APTT
Blood bankVery critical section
Bec. May have errors Blood typing Cross match
Goes hand in hand with serology and immunology
Tests done for MALARIA SYPHILIS HIV
Serology/Immunology Cardiac and thyroid fxntest
II. ANATOMY PATHOLOGY
Histopathology
SAMPLE
A sample of a material to be tested or analyzed
that is prepared from a gross sample and retains the latter's composition.
SPECIMENS WHICH ARE USED IN LAB FOR TESTING Venous blood, serum or plsma. Arterial blood Capillary blood Urine Faeces Cerebrospinal fluid Sputum and saliva Tissue and cells Calculi Aspirates e.g.
Pleural fluid Ascites Synovial fluid Intestinal Pancreatic
NATURE OF REQUEST
STAT
Performed immediately and by itself
Run control and standard
20-50% More expensive
TAT is shortened Request is needed
Today
Confusing Performed as
soon as possible, given priority
Based on “running time”
Routine Done with the batch Wait for TAT stated
by laboratory
AUTOMATION AND COMPUTERIZATION
Test Repertoire (Range) More than 400 tests can be performed in the lab Analyzers
Laboratory personnels
VALUES
REFERENCE VALUES Better term than
“normal value” Pulled value, usually
95%of population Vary in diff. hospitals
but not that far
SIGNIFICANT VALUES Clinical decision
should be made if higher or lower than reference value
Usually when 2x to 3x
CRITICAL VALUES
Needs immediate attention “panic values” Should call physician Patient is at risk
Glucose less than 45mg/dl More than 500mg/dl Potassium less than 6.6 g/dl More than 19.9 g/dl
REFERENCE VALUES
Not fixed for allShould consider:
Age Sex Pregnancy Diurnal Variation Race Blood type
ROUTINE EXAMINATIONS
ROUTINE ADMISSION TESTS CBC, Urinalysis, Fecalysis
ROUTINE CHEMISTRIES BUN, Creatinine, Glucose, Uric Acid, Cholesterol
Sometimes triglycerides
SPECIMEN COLLECTION
Correct sample Correct information (history) More information is required while
reassessing or assessing prognosis. Identification must be clear and correct.
QUALITY ASSURANCE TO OBTAIN CORRECT TEST RESULTS
Immediate and long term clinical, public health, andhealth planning decisions are based on the results oflaboratory tests. Incorrect, delayed, or misinterpretedtest results can have serious consequences forpatients and communities, undermine confidence inthe service, and waste scarce district healthresources. Achieving reliability of test results is dependent on: Understanding what are the commonest causes of
inaccuracy and imprecision in the performance of tests and of delayed or misinterpreted
and sources of error). Taking the necessary steps to prevent and minimize errors by:
– implementing Standard Operating Procedures (SOPs) with quality control for all district laboratory activities.
– introducing every month a quality control day and an external quality assessment scheme for outreach laboratories (see later text, Role of the district medical officer in TQM).
– appointing a district laboratory coordinator to monitor the performance of district laboratories (see later text).
Agreeing with those requesting laboratory tests, policies of work that will enable the laboratory to provide an efficient, safe, cost-effective, and reliable service (see subunit 2.4).
Maintaining good communications between laboratory staff and those requesting tests.