Very little is known about pathology and various misconceptions have arisen about this service.
We have analysed the situation and arrived at the perfect diagnosis
- to inform you about the complex and comprehensive workings of the
pathology laboratory.
The Pathology laboratory
After listening to a patient's complaints and performing a thorough
physical examination, a doctor will diagnose the disease, institute
the most appropriate therapy and thereafter monitor the results.
He might need the back up of additional tests such as laboratory
investigations, which enable him to diagnose, detect, or exclude
disease more reliably.
Prudent use of the pathology laboratory by the clinical team is
essential to improve diagnostic ability, thus reducing the period of
illness by the efficient institution of the most appropriate
therapy.
In order to achieve this goal, specimens must be transported rapidly
to the laboratory for accurate analysis by the pathologist and a
team of highly trained medical technologists.
Large numbers of specimens are processed daily. Correct specimen
identification and handling is critical. Elaborate procedures
designed to minimize the possibility of human error have been set
up.
Sophisticated, analytical equipment, linked to advanced computer
systems, is used in the analysis of specimens.
Quality assurance is considered a priority and so both local and
international quality control programs are adhered to. The modern
pathology laboratory is equipped with state-of-the-art technology
and is run by highly trained people.
The comprehensive pathology laboratory encompasses four disciplines.
Clinical Chemistry
More than 120 different tests, profiles and screening panels can be
performed. A variety of chemical components, proteins and hormones
present in blood and other body fluids, found normally or in diseased
states, are measured.
Chemical profiles and screening panels are specifically designed to
detect susceptibility to kidney disease, liver disease, diabetes,
and iron deficiency and thyroid dysfunctions amongst others.
Abnormal results lead to more definitive testing after consultation
between the referring doctor and the pathologist. Many chemistry
tests are particularly useful in monitoring the course of a disease
and the effect of the chosen therapy.
The toxicology section detects and monitors the level of
drugs or poisons in specimens. Blood levels are monitored in
industrial employees exposed to toxic compounds, such as lead.
Similarly, blood levels of therapeutic agents, such as
anticonvulsants taken by epileptics, require monitoring.
Haematology: the study of blood disease The most commonly performed test in the laboratory is the counting
and categorizing of blood cells (known as the full blood count).
Complex machines are used for this and the blood slides are examined
microscopically. This is often the first-line screening test for
disease or to detect specific conditions such as anaemia or leukaemia.
Te pathologist often consults with the referring doctor, suggesting
further tests, if indicated. The clotting ability of the blood is
also evaluated in patients with abnormal bleeding or bruising to
detect the possible causes.
Microbiology and Serology:
the study of infectious diseases.
Microbiology is primarily engaged in the testing of patient
specimens (e.g. urine, pus and sputum) for the presence of
micro-organisms (germs).
Micro-organisms are cultured in patient specimens, so that the germ
causing the infection may be identified and its sensitivity to
antibiotics determined. This allows for the early administration of
the most appropriate antibiotic, thus reducing the periods of
illness.
Serology implies the screening of patient serum for antibodies
produced by the body in defence of germs, such as the viruses
causing AIDS, German measles and hepatitis, which are not easily
cultured.
Anatomical Pathology Histology is
the study of diseased tissue.
This department is mainly employed in the analysis of tissue and
organs from the operating
theatre. Extremely thin sections of tissue
are stained and consequently examined microscopically by the
pathologist.
Specific reaction patterns are described for certain causative
agents such as tuberculosis. Malignancies (cancerous growths) are
assessed for completeness of removal and to assist in determining
the prognosis (long-term outlook).
The frozen section biopsy technique is used intra-operatively to
instruct the surgeon on the most appropriate therapy for a
particular tumour, in many cases doing away with subsequent surgery
and extra expense.
Cytology: the study of exfoliated cells
Superficial cells derived from various sites (e.g. cervix in a PAP
smear) are examined for microscopic abnormalities. Early detection
of potential malignancies favours the possibility of cure by timely
therapy.