In the clinical laboratory, tests are performed on various specimens, including blood, body fluids, cultures, and more. Results are then reported to the ordering clinician.
Commonly requested tests are performed in-house, while less commonly requested tests may be sent to a reference laboratory.
The clinical laboratory can be divided into various departments, each staffed by medical laboratory scientists (MLS) and medical laboratory technicians (MLT). MLSs and MLTs are trained to perform specific tests and to operate and monitor automated instruments within their department(s). Each department is overseen by a qualified supervisor or a lead MLS/MLT.
Departments within the clinical laboratory include data management, specimen collection and processing, hematology and coagulation, chemistry, immunology and serology, transfusion services, microbiology, and molecular diagnostics. In all of these departments, specialized automated instruments ensure analysis quality and deliver results to the patient's electronic medical record (EMR).
The data management department is where the laboratory information system (LIS) and its communication with analyzers are managed.
The specimen collection and processing department is where specimens are collected and processed before being sent to the necessary department(s) for testing. Blood is the most common specimen collected and received from outpatient collection areas. Tasks in the specimen collection and processing department are also performed by phlebotomists and medical laboratory assistants (MLA).
The hematology department is where cellular components of the blood—red blood cells, white blood cells, and platelets—are tested. Coagulation, or the blood's ability to clot, is also tested in this department.
The chemistry department is where blood plasma and serum are tested for various analytes. An example of an analyte is an electrolyte, such as sodium (Na+), chloride (Cl-), and potassium (K+). Urinalysis, or the analysis of urine, is performed in this department or hematology.
The transfusion services department is where blood donor units are matched with blood recipients. The transfusion services department receives and tests donor blood components for compatibility with patient samples. It requires high quality control since erroneous compatibility results can cause serious adverse outcomes for the patient.
The microbiology department is where microorganisms within a patient specimen are grown for identification, known as "culturing." After microorganisms are cultured, they are tested for identification and other relevant findings, such as antibiotic sensitivity, which reveals the most effective antibiotic treatment for a patient's infection.
The molecular diagnostics department is where molecules like DNA and RNA are tested to produce diagnostic results. The most common laboratory technique is the polymerase chain reaction (PCR), which helps identify bacterial or viral infections, including HPV and COVID-19.
3. Gathany, James."This photograph depicted an Enteric Diseases Laboratory Branch (EDLB), Public Health scientist, who was testing bacterial samples for their antimicrobial susceptibility." CDC Public Health Image Library, 2019, https://phil.cdc.gov/Details.aspx?pid=23182.
4. Gathany, James."This photograph depicted an Enteric Diseases Laboratory Branch (EDLB), Public Health scientist, who was setting up a molecular test called a polymerase chain reaction (PCR), in order to detect specific bacterial DNA in a sample." CDC Public Health Image Library, 2019, https://phil.cdc.gov/Details.aspx?pid=23174.
