Pathology is a branch of medicine that deals with the diagnosis and study of disease. It covers a wide range of topics, from the study of individual cells to the investigation of whole organs and systems. Pathologists use a variety of techniques to examine tissues and organs, including microscopy, histology, immunology, molecular biology and genetics.
The word pathology comes from the Greek pathos, meaning “suffering” or “disease”. Pathologists are often called “the detectives of medicine” because their work involves solving puzzles to determine the cause of disease. In many cases, pathology is used to confirm a diagnosis made using other methods such as clinical examination or radiology.
Pathologists work in hospital laboratories where they examine tissues removed during surgery (biopsies) or post-mortem examinations (autopsies). They also examine fluids such as blood and urine for evidence of disease. In some cases, pathologists may be asked to give expert testimony in court about their findings.
The main types of pathology are histopathology, cytopathology and immunopathology. Histopathology is the study of tissue changes at the microscopic level using stains and specialised techniques such as electron microscopy. Cytopathology is the study of changes in cells that can be seen with a microscope; it includes tests such as Pap smears for cervical cancer screening. Immunopathology is concerned with how diseases develop when the body’s immune system is not working properly.