Martwica

Martwica, also known as necrosis, is a form of cell death that occurs in living tissue. It is an irreversible process resulting from injury, such as infection, toxins, or trauma. Unlike apoptosis, which is programmed cell death, necrosis is a pathological process.

The process of necrosis typically begins with cell swelling and the rupture of the cell membrane. This leads to the release of cellular contents into the surrounding tissue, triggering an inflammatory response. The extracellular matrix can also be affected, leading to structural changes in the tissue.

There are several types of necrosis, classified based on their gross and microscopic appearance. Coagulative necrosis is characterized by the preservation of the basic cell outline, often seen in myocardial infarction. Liquefactive necrosis involves the digestion of cells, resulting in a liquid mass, common in brain infarction or bacterial infections. Caseous necrosis, a distinct form, resembles cheese and is typically associated with tuberculosis. Fat necrosis occurs in fatty tissues and can be seen after pancreatitis or trauma. Gangrenous necrosis is a clinical term, often referring to the death of a limb due to ischemia, which can be either coagulative or liquefactive.

The causes of necrosis are diverse and include ischemia (lack of blood supply), infection (bacterial, viral, fungal), toxins (chemical or biological), physical agents (trauma, burns, radiation), and immunological reactions.

The clinical manifestations of necrosis depend on the location and extent of the affected tissue. Symptoms can range from pain and swelling to loss of function and systemic effects like fever. Diagnosis is usually made through clinical examination, imaging studies, and histopathological examination of tissue samples. Treatment focuses on addressing the underlying cause of the necrosis and managing complications. In some cases, surgical debridement of necrotic tissue may be necessary to prevent further spread of infection or damage.