Anatomic pathology 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. Anatomic pathology is the discipline that relies on direct visualization of human tissue, both grossly and microscopically, to render appropriate diagnoses, the purpose of identifying and classifying microorganisms in biopsy or excisional specimens. Gram stain and various acid-fast stains still have broad usage for detecting bacteria and mycobacteria, respectively. Anatomic pathology is the branch of medicine that studies the effect of disease on the structure of body organs, both as a whole and microscopically. The primary role of anatomic pathology is to identify abnormalities that can help to diagnose disease and manage treatment.
Anatomic pathology is somewhat different from clinical pathology, which deals with the measurement of chemical constituents of blood and other body fluids, analysis of blood cells and identification of microbes. While most of the tests described on this site would be categorized as clinical pathology, many are used in conjunction with anatomic pathology procedures. In fact, technical advances are blurring the distinctions between the two in many areas. Overlaps include, for example, flow cytometry, cytogenetics and molecular pathology, which can be performed on both tissue samples and blood or body fluid samples.
There are two main subdivisions within anatomic pathology: Histopathology: Which involves examination of intact tissue from biopsy or surgery under the microscope; this is often aided by the use of special staining techniques and other associated tests, such as using antibodies to identify different components of the tissue.
Cytopathology: Which is the examination of single cells or small groups of cells from scrapings or aspiration of fluid or tissue under the microscope, a common cytology test is the cervical Pap smear. Technologists often screen preparations and report results but, in many cases, the pathologist gives the definitive diagnosis to the healthcare practitioner. Anatomic pathologists are also involved in performing post-mortem examinations (autopsies). An autopsy may be performed after a person has died of an illness that could not, for whatever reason, be properly or fully diagnosed before death. The physician will seek consent from the family to have an autopsy performed. If the cause of death is suspicious or related to an illegal activity, the autopsy will be performed by a forensic pathologist.
Histopathology: Histopathology involves the examination of sampled tissues under the microscope. These may be small pieces of tissue obtained from a part of the body using a technique called biopsy or samples taken from whole organs or parts of organs removed during surgery.
Cytopathology: Cytology is the study of individual cells and cytopathology is the study of individual cells in disease, although the two terms are often used interchangeably. Sampled fluid and/or tissue from a patient is smeared onto a slide and stained.
Katherine Gray| Managing Editor
Archives of Clinical Pathology
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