The term pathogenesis means step by step development of a disease due to a series of changes in the structure and /or function of a cell/tissue/organ being caused by a microbial , chemical or physical agent.The pathogenesis
of a disease
is the mechanism
by which an etiological
factor causes the disease. The term can also be used to describe the development of the disease, such as acute
. The word comes from the Greek pathos
, "disease", and genesis
Types of pathogenesis include microbial infection, inflammation, malignancy and tissue breakdown.
Most diseases are caused by multiple pathogenetical processes together. For example, certain cancers arise from dysfunction of the immune system (skin tumors and lymphoma after a renal transplant, which requires immunosuppression).
Often, a potential etiology is identified by epidemiological observations before a pathological link can be drawn between the cause and the disease.