Organization
Clinical pathologists are often medical doctors. In some countries in South-America, Europe, Africa or Asia, this specialty can be practiced by non-physicians, such as Ph.D. or Pharm.D. after a variable number of years of residency.
In United States of America
Clinical pathologists work in close collaboration with clinical scientists (clinical biochemists, clinical microbiologists, etc.), medical technologists, hospital administrators, and referring physicians to ensure the accuracy and optimal utilization of laboratory testing.
Clinical pathology is one of the two major divisions of pathology, the other being anatomical pathology. Often, pathologists practice both anatomical and clinical pathology, a combination sometimes known as general pathology. Similar specialties exist in veterinary pathology.
Clinical pathology is itself divided into subspecialties, the main ones being clinical chemistry, clinical hematology/blood banking, hematopathology and clinical microbiology and emerging subspecialties such as molecular diagnostics and proteomics. Many areas of clinical pathology overlap with anatomic pathology. Both can serve as medical directors of CLIA certified laboratories. Under the CLIA law, only the US Department of Health and Human Services approved Board Certified Ph.D., DSc, or MD and DO can perform the duties of a Medical or Clinical Laboratory Director. This overlap includes immunoassays, flow cytometry, microbiology and cytogenetics and any assay done on tissue. Overlap between anatomic and clinical pathology is expanding to molecular diagnostics and proteomics as we move towards making the best use of new technologies for personalized medicine. [3]
Clinical pathologists may assist physicians in interpreting complex tests such as platelet aggregometry, hemoglobin or serum protein electrophoresis, or coagulation profiles. If interfering substances are suspected, they may recommend alternate test methods. For example, hemolysis, icterus, lipemia, or heterophile antibodies may confound results obtained by traditional methods such as ion-selective electrodes, enzymatic assays or immunoassays. Alternate methods such as blood gas analysers, point-of-care testing or mass spectrometry may help resolve the clinical question.
In Europe
Recently, EFLM has chosen the name of "Specialists in Laboratory Medicine" to define all European Clinical pathologists, regardless of their training (M.D., Ph.D. or Pharm.D.). [4]
In France, Clinical Pathology is called Medical Biology ("Biologie médicale") and is practiced by both M.D.s and Pharm.D.s. The residency lasts four years. Specialists in this discipline are called "Biologiste médical" which literally translates as Clinical Biologist rather than "Clinical pathologist". [5]
Microscopes, analyzers, strips, centrifuges
Macroscopic examination
Visual examination of the specimen may provide information to the pathologist or the physician. For example, fluid drained from an abscess may appear cloudy, or cerebrospinal fluid obtained by lumbar puncture may exhibit xanthochromia, suggesting a bleed has occurred. Laboratory technologists may provide qualitative descriptions accordingly.
Microscopical examination
Microscopic analysis is an important activity of the pathologist and the laboratory technologist. They have many different stains at their disposal (GRAM, MGG, Grocott, Ziehl–Neelsen, etc.). Immunofluorescence, cytochemistry, the immunocytochemistry, and FISH are also used in order make a correct diagnosis.
Pathologists may review samples such as pleural, peritoneal, synovial, or pericardial fluids to characterize them as "normal", tumoral, inflammatory, or even infectious. Microscopic examination can also determine the causal infectious agent – often a bacterium, mould, yeast, parasite, or (rarely) virus.
Laboratory Analysers
Automated analysers, by the association of robotics and spectrophotometry, have allowed these last decades better reproducibility of the results, in particular in medical biochemistry and hematology. [6]
Efficiency and productivity can be enhanced by automating the pre-analytical processing, including barcode reading, sorting, centrifuging, and aliquoting specimens.
The analysers must undergo daily controls prior to performing patient testing. Analysers must also undergo daily, weekly and monthly maintenance. Quality management involves reviewing quality control trends to detect emerging problems in instrument calibration, correlating results between instruments that perform similar testing, and running standardized samples to prove linearity and precision.
Some laboratory processes involve automated analysis combined with manual review by technologists. For example, when hematology analysers flag samples as abnormal, automated white blood cell differential counts may be superseded by manual differential counts using stained slides read at the microscope or scanned by digital imaging software. Laboratory technologists may flag abnormal samples for pathologist review. The pathologist may recommend additional testing, such as flow cytometry to identify lymphoma or leukemia cells, or cytology to characterize solid tumor cells.
Cultures
Samples undergoing examination for pathogens, primarily in medical microbiology, may be incubated with culture media. Those allow, for example, the description of one or several infectious agents responsible of the clinical signs.
Values known as "normal" or reference values
Detailed article: Reference range.
Pathology is the study of disease and injury. The word pathology also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when used in the context of modern medical treatment, the term is often used in a narrower fashion to refer to processes and tests that fall within the contemporary medical field of "general pathology", an area that includes a number of distinct but inter-related medical specialties that diagnose disease, mostly through analysis of tissue and human cell samples. Idiomatically, "a pathology" may also refer to the predicted or actual progression of particular diseases, and the affix pathy is sometimes used to indicate a state of disease in cases of both physical ailment and psychological conditions. A physician practicing pathology is called a pathologist.
Anatomical pathology (Commonwealth) or anatomic pathology (U.S.) is a medical specialty that is concerned with the diagnosis of disease based on the macroscopic, microscopic, biochemical, immunologic and molecular examination of organs and tissues. Over the 20th century, surgical pathology has evolved tremendously: from historical examination of whole bodies (autopsy) to a more modernized practice, centered on the diagnosis and prognosis of cancer to guide treatment decision-making in oncology. Its modern founder was the Italian scientist Giovanni Battista Morgagni from Forlì.
Hematology is the branch of medicine concerned with the study of the cause, prognosis, treatment, and prevention of diseases related to blood. It involves treating diseases that affect the production of blood and its components, such as blood cells, hemoglobin, blood proteins, bone marrow, platelets, blood vessels, spleen, and the mechanism of coagulation. Such diseases might include hemophilia, sickle cell anemia, blood clots (thrombus), other bleeding disorders, and blood cancers such as leukemia, multiple myeloma, and lymphoma. The laboratory analysis of blood is frequently performed by a medical technologist or medical laboratory scientist.
Forensic pathology is pathology that focuses on determining the cause of death by examining a corpse. A post mortem examination is performed by a medical examiner or forensic pathologist, usually during the investigation of criminal law cases and civil law cases in some jurisdictions. Coroners and medical examiners are also frequently asked to confirm the identity of remains.
Clinical chemistry is a division in medical laboratory sciences focusing on qualitative tests of important compounds, referred to as analytes or markers, in bodily fluids and tissues using analytical techniques and specialized instruments. This interdisciplinary field includes knowledge from medicine, biology, chemistry, biomedical engineering, informatics, and an applied form of biochemistry.
Phlebotomy is the process of making a puncture in a vein, usually in the arm, with a cannula for the purpose of drawing blood. The procedure itself is known as a venipuncture, which is also used for intravenous therapy. A person who performs a phlebotomy is called a phlebotomist, although most doctors, nurses, and other technicians can also carry out a phlebotomy. In contrast, phlebectomy is the removal of a vein.
Transfusion medicine is the branch of medicine that encompasses all aspects of the transfusion of blood and blood components including aspects related to hemovigilance. It includes issues of blood donation, immunohematology and other laboratory testing for transfusion-transmitted diseases, management and monitoring of clinical transfusion practices, patient blood management, therapeutic apheresis, stem cell collections, cellular therapy, and coagulation. Laboratory management and understanding of state and federal regulations related to blood products are also a large part of the field.
An automated analyser is a medical laboratory instrument designed to measure various substances and other characteristics in a number of biological samples quickly, with minimal human assistance. These measured properties of blood and other fluids may be useful in the diagnosis of disease.
A veterinary specialist is a veterinarian who specializes in a clinical field of veterinary medicine.
A Medical Laboratory Scientist (MLS) or Clinical Laboratory Scientist (CLS) or Medical Technologist (MT) performs diagnostic testing of blood and body fluids in clinical laboratories. The scope of a medical laboratory scientist's work begins with the receipt of patient or client specimens and finishes with the delivery of test results to physicians and other healthcare providers. The utility of clinical diagnostic testing relies squarely on the validity of test methodology. To this end, much of the work done by medical laboratory scientists involves ensuring specimen quality, interpreting test results, data-logging, testing control products, performing calibration, maintenance, validation, and troubleshooting of instrumentation as well as performing statistical analyses to verify the accuracy and repeatability of testing. Medical laboratory scientists may also assist healthcare providers with test selection and specimen collection and are responsible for prompt verbal delivery of critical lab results. Medical Laboratory Scientists in healthcare settings also play an important role in clinical diagnosis. An estimated 70% of medical decisions are based on laboratory test results and MLS contributions affect 95% of a health system's costs.
Hematopathology or hemopathology is the study of diseases and disorders affecting and found in blood cells, their production, and any organs and tissues involved in hematopoiesis, such as bone marrow, the spleen, and the thymus. Diagnoses and treatment of diseases such as leukemia and lymphoma often deal with hematopathology; techniques and technologies include flow cytometry studies and immunohistochemistry.
Medical laboratory assistants (MLAs) also known as clinical laboratory assistants (CLA) or clinical assistants (CA) prepare, and in some cases process samples within a pathology laboratory. They also utilise pre-analytical systems in order for biomedical scientists (BMS) or Medical Laboratory Scientific Officers to process the biochemical tests requested on the sample. The majority of an MLA's time is spent in processing specimens. As such, the MLA has to have excellent knowledge of their particular sample acceptance policy, whilst obeying the data protection act, patient confidentiality, COSHH and the Caldicott rules.
Veterinary pathologists are veterinarians who specialize in the diagnosis of diseases through the examination of animal tissue and body fluids. Like medical pathology,veterinary pathology is divided into two branches, anatomical pathology and clinical pathology. Other than the diagnosis of disease in food-producing animals, companion animals, zoo animals and wildlife, veterinary pathologists also have an important role in drug discovery and safety as well as scientific research.
A medical laboratory or clinical laboratory is a laboratory where tests are conducted out on clinical specimens to obtain information about the health of a patient to aid in diagnosis, treatment, and prevention of disease. Clinical medical laboratories are an example of applied science, as opposed to research laboratories that focus on basic science, such as found in some academic institutions.
Rodney Smith Markin, is an American pathologist and authority in the field of laboratory automation. In 1993, he designed and created one of the world's first automated clinical laboratory specimen, device and analyzer management systems. In the mid-1990s, he chaired a standards group called the Clinical Testing Automation Standards Steering Committee (CTASSC) of the American Association for Clinical Chemistry, which later evolved into an area committee of the Clinical and Laboratory Standards Institute.
For the Irish playwright and screenwriter, see Nancy Harris.
A pathologists’ assistant (PA) is a physician extender whose expertise lies in gross examination of surgical specimens as well as performing forensic, medicolegal, and hospital autopsies.
Elaine Sarkin Jaffe is a senior National Cancer Institute (NCI) investigator at the National Institutes of Health (NIH) most well known for her contribution to hematopathology. She completed her medical education at Cornell University and the University of Pennsylvania, receiving her M.D. degree from University of Pennsylvania in 1969. After an internship at Georgetown University she joined NCI as a resident in anatomic pathology, and has been a senior investigator since 1974, focusing on the classification and definition of lymphomas. Jaffe's early work helped to provide a deeper understanding of the origin of lymphomas, especially follicular lymphoma. Her team notably elucidated the difference between T cell and B cell lymphomas.
The American Board of Pathology (ABPath) is one of 24 member boards of the American Board of Medical Specialties. This organization was assembled in May 1936, under the approval of the Advisory Board for Medical Specialties (ABMS) and the American Medical Association (AMA) Council on Medical Education and Hospitals. It is the duty of the ABPath to grant certification in Anatomic Pathology, Clinical Pathology and/or Anatomic/Neuropathology to qualified Doctors of Medicine and Doctors of Osteopathic Medicine (M.D./D.O.).
A white blood cell differential is a medical laboratory test that provides information about the types and amounts of white blood cells in a person's blood. The test, which is usually ordered as part of a complete blood count (CBC), measures the amounts of the five normal white blood cell types – neutrophils, lymphocytes, monocytes, eosinophils and basophils – as well as abnormal cell types if they are present. These results are reported as percentages and absolute values, and compared against reference ranges to determine whether the values are normal, low, or high. Changes in the amounts of white blood cells can aid in the diagnosis of many health conditions, including viral, bacterial, and parasitic infections and blood disorders such as leukemia.
