Pathology deals with the assessment and determination of causes of pathological changes in the organism. In doing so, it works closely with anatomy, pathophysiology and cytology. In medicine, it is an important tool for quality assurance.
What is pathology?
Pathology is a branch of medicine that deals with the symptoms and symptom complexes of pathological processes as well as their causes. The term pathology is derived from the Greek word “pathologia”, which means disease, suffering or passion. In this sense, pathology is defined as the study of disease or illness. It is a branch of medicine that deals with the symptoms and symptom complexes of pathological processes as well as their causes. Furthermore, it examines the origin, the mode of development and the effects of diseases. For this purpose, pathology has many examination possibilities at its disposal. It examines both macroscopic and microscopic changes and therefore works closely with the subfields of anatomy, cytology and pathophysiology. However, it must be distinguished from forensic medicine, which deals only with unnatural causes of death, but uses similar examination methods. Sometimes the terms are difficult to separate because the term “pathology” is also used figuratively to refer to a pathology department or institute.
Function, effect, and goals
As already mentioned, pathology in the true sense deals with the development, identification, course and effects of diseases. In doing so, it makes use of various methods of investigation. Thus, pathological diagnosis is based on the assessment of tissues by macroscopic and microscopic examination. In macroscopic assessment, the aim is to detect pathological anatomical changes already by visual inspection, which can provide an indication of certain pathological processes. For example, conspicuous color changes can be detected in tissue samples, which, in conjunction with other symptoms that occur, can indicate certain diseases. Microscopic examinations using light microscopy register abnormalities at the cellular level. This method can often be used to assess the malignancy of the cells under examination. Pathology is also increasingly using biochemical and molecular biological methods for diagnostics. Electron microscopy is also being used to an increasing extent in pathological research. In addition to the examination of living tissue, pathology also performs autopsies (post-mortem examinations). Autopsies are used to determine the natural cause of death. The aim here is to find out which pathological processes specifically led to death. However, in pathology, the examination of living tissue (biopsy) predominates by far. In a biopsy, tissue samples are taken by a physician and examined by a pathologist. The pathologist processes small samples into sectional preparations and examines them under a light microscope. After preparation, he first evaluates large pieces of tissue macroscopically. Sections of tissue that appear unusual are cut out of the specimen again and prepared for microscopy. Microscopy often gives the pathologist an indication of the nature of the pathological change and its severity. In this way, any cancer cells can be identified and the affected areas determined. If a tumor is present, its type, size, extent, and malignancy can be assessed. Today, in addition to histological (microscopic examination of tissue), immunological, biochemical and molecular biological examinations of the tissue are also performed. The examination of the tumor at the molecular level can be decisive for the choice of a particular form of therapy. A second important field of pathology is, as already mentioned, the autopsy of cadavers. An autopsy can only be performed if the relatives of the deceased agree to it. It serves to clarify the cause of death, can confirm the doctor in the correctness of his treatment method and reveals any risk factors lying in the family, such as genetic factors. It is important to note that the pathologist performs autopsies only to determine natural causes of death.If there is a suspicion of an unnatural cause of death, such as an accident or murder, the forensic pathologist deals with this. The third task of pathology is quality assurance in order to maintain and constantly improve medical standards. According to the type of pathological examination, pathology has split into four different subfields. Thus, pathological anatomy deals with the examination of pathological tissue changes by mere visual inspection. Histopathology, as the most common method of examination, involves the histological examination of tissue samples by microscopic and immunohistological methods. In cytopathology, single cells instead of tissues are examined for pathological changes. Finally, molecular pathology, the fourth branch of pathology, is used to evaluate single cells and tissues at the molecular level.
Special features
Pathologic changes are specific to all organic structures, so each branch of medicine and even each form of organism has its own pathology. For example, in the case of the nervous system, the term neuropathology is used. Neuropathology is a branch of pathology that deals specifically with diseases of the nervous system and brain. In contrast to neurology, neurosurgery and psychiatry, it is a clinical theoretical subject, which serves as a basis for diagnosis, therapy and prophylaxis of neurological diseases. Furthermore, because of the difference in pathology, human and veterinary medicine also represent separate medical fields. The difficult demarcation of pathology from other medical specialties in general linguistic usage is also expressed in the case of autopsy. Thus, colloquially, an autopsy is always assigned to pathology, regardless of the cause of death. However, in the case of unnatural deaths (homicide, accident), forensic pathologists are used for the examination. Only when natural causes of death are to be determined are autopsies always performed by pathologists.
