Medical laboratory
From Wikipedia, the free encyclopedia
A medical laboratory or clinical laboratory is a laboratory where tests are done on biological specimens in order to get information about the health of a patient.
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[edit] Departments
The laboratory is often divided into a number of disciplines:
- Microbiology receive swabs, feces, urine, blood, sputum, medical equipment, as well as possible infected tissue. They culture this to check for any pathogenic microbes.
- Hematology receive whole blood and citrated plasma. They do full blood counts, blood films and coagulation investigations.
- Biochemistry usually receive serum. They test the serum for different components.
- Immunology test for antibodies.
- Histology process solid tissue removed from the body to make slides and examine cellular detail.
- Cytology examine smears of cells (such as from the cervix) for evidence of cancer and other conditions.
- Cytogenetics involves using blood and other cells to get a karyotype. This can be helpful in prenatal diagnosis (e.g. Down's syndrome) as well as in cancer (some cancers have abnormal chromosomes).
- Virology and DNA analysis are also done in large medical laboratories.
[edit] Types of laboratory
In many countries, there are two main types of labs that process the majority of medical specimens. Hospital laboratories are attached to a hospital, and perform tests on these patients. Private (or community) laboratories receive samples from general practitioners, insurance companies, and other health clinics for analysis.
For extremely specialised tests, samples may go to an environmental science or research laboratory.
A lot of samples are sent between different labs for uncommon tests. It is more cost effective if a particular laboratory specialises in a rare test, receiving specimens (and money) from other labs, while sending away tests it cannot do.
[edit] Sample processing
Sample processing will usually start with a set of samples and a request form.
Typically a set of vacutainer tubes containing blood, or any other specimen will arrive to the laboratory in a small plastic bag, along with the form.
The form and the specimens are given a laboratory number. The specimens will usually all receive the same number, often as a sticker that can be placed on the tubes and form. Entry of requests onto a laboratory management system involves typing, or scanning (where barcodes are used) in the laboratory number, and entering the patient identification, as well as any tests requested. This allows laboratory machines, computers and staff to know what tests are pending, and also gives a place (such as a hospital department, doctor or other customer) for results to go.
For biochemistry samples, blood is usually centrifuged and serum is separated. If the serum needs to go on more than one machine, it can be divided into separate tubes.
Many specimens end up in one or more sophisticated automated analyser, that process a fraction of the sample and return one or more "results".
[edit] Laboratory Informatics
Laboratories today are held together by a system of software programs and computers that exchange data about patients, test requests and test results, known as Laboratory information system.
This system enables hospitals and labs to send the correct test requests for each sample and keep track of individual patient or sample history, and help to guarantee a better quality of results, as well as publishing the results for doctors to check and patients to read.
