pathology

pathology, study of the cause of disease and the modifications in cellular function and changes in cellular structure produced in any cell, organ, or part of the body by disease. The changes in tissue include degeneration, atrophy, hypertrophy, hyperplasia, and inflammation. The microscope is an important factor in detecting tissue changes, especially in the examination of small sections of tissue removed for diagnosis (biopsy); for this reason real progress in pathology was not made until the 19th cent. Other diagnostic techniques for testing body fluids and tissues for abnormal composition or metabolisms are electronmicroscopy, immunocytochemistry, and molecular pathologies.

Medical specialty dealing with causes of disease and structural and functional changes in abnormal conditions. As autopsies, initially prohibited for religious reasons, became more accepted in the late Middle Ages, people learned more about the causes of death. In 1761 Giovanni Battista Morgagni (1682–1771) published the first book to locate disease in individual organs. In the mid-19th century the humoral theories of infection were replaced first by cell-based theories (see Rudolf Virchow) and then by the bacteriologic theories of Robert Koch and Louis Pasteur. Today pathologists work mostly in the laboratory and consult with a patient's physician after examining specimens including surgically removed body parts, blood and other fluids, urine, feces, and discharges. Culturing of infectious organisms, staining, fibre-optic endoscopy, and electron microscopy have greatly expanded the information available to the pathologist.

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Pathology (from Greek πάθος, pathos, "fate, harm"; and -λογία, -logia) is the study and diagnosis of disease through examination of organs, tissues, bodily fluids and whole bodies (Autopsy). The term also encompasses the related scientific study of disease processes, called General pathology.

Medical pathology is divided in two main branches, Anatomical pathology and Clinical pathology. Veterinary pathology is concerned with animal disease whereas Phytopathology is the study of plant diseases.

History of pathology

General pathology

Pathology as a medical specialty

Anatomical pathology

Clinical pathology

Forensic pathology

Veterinary pathology

Plant pathology

See also

• Molecular pathology
• Medical laboratory
• Important publications in pathology

External links

• Association of Clinical Biochemistry (UK)
• American Society for Investigative Pathology
• American Society of Cytopathology
• British Neuropathological Society
• Case Records of the Massachusetts General Hospital - Clinicopathological Conference
• College of American Pathologists
• Flickr group: Pathology and Lab Medicine: numerous photos illustrating the work of pathologists.
• HistoPathology Atlas
• humpath.com (Atlas in Human Pathology)
• Immunohistochemistry protocols and troubleshooting
• Mybiopsy.org
• Neuropathology blog
• Pathological Society of Great Britain and Ireland
• Royal College of Pathologists (UK)
• Royal College of Pathologists of Australasia (Australia & Oceania)
• Sullivan Nicolaides Pathology - Leading Australian Pathology Laboratory.
• United States and Canadian Academy of Pathology
• WebPath: The Internet Pathology Laboratory for Medical Education
• Pathtalk.org - A community weblog about pathology-related topics.
• What is a Pathologist? - a perspective from UK pathologist Fraser Charlton.
• Pathologypics - an interactive community-driven histology atlas