nekróze

Nekróza is a medical term referring to the irreversible death of cells and tissues within a living organism. It is a pathological process that occurs when cells are subjected to severe injury or stress from which they cannot recover. Unlike apoptosis, which is programmed cell death, necrosis is typically a result of external factors that compromise the cell's integrity.

The causes of necrosis are varied and can include lack of blood supply (ischemia), physical trauma, exposure to toxins, infections, and extreme temperatures. When cells die due to necrosis, they swell and their membranes rupture, releasing their contents into the surrounding tissues. This release triggers an inflammatory response, as the body attempts to clear away the dead cells and repair the damaged area.

Different types of necrosis exist, often categorized by their gross and microscopic appearance. For instance, coagulative necrosis, common in hypoxic tissues like the heart, involves cell shrinkage and denaturation of proteins while maintaining the basic cell outline. Liquefactive necrosis, seen in brain tissue or abscesses, results in the dissolution of cells and the formation of a liquid mass. Caseous necrosis, often associated with tuberculosis, appears cheesy and crumbly. Fat necrosis occurs in fatty tissues, such as the breast or pancreas, and can be caused by trauma or enzymatic activity.

The consequences of necrosis depend on the extent of tissue damage and the organ affected. It can impair organ function and, in severe cases, lead to systemic complications or even death. Treatment focuses on addressing the underlying cause of the necrosis and managing the inflammatory response.