Diagnosis | Necrosis

Diagnosis

The diagnostic procedure depends on the location of the necrosis. If it is an external necrosis, for example skin necrosis, a physician can make a diagnosis after closer examination. In addition, a smear of the wound is taken to determine whether pathogens are present in the necrosis.

However, if the necrosis is internal, for example bone or organ necrosis, imaging is required. This is usually done by MRI (magnetic resonance imaging) or CT (computed tomography). First impressions and a suspected diagnosis can also be obtained by performing an ultrasound of the affected area.

More specific, however, is more complex imaging. In the case of necroses, medicine does not generally classify them according to stage. A distinction is usually made according to the type and location of necrosis.

For example, a decubitus is divided into four different stages (according to EPUAP). The depth of the wound and the involvement of certain structures play a major role. According to Wagner and Armstrong, necroses in the context of diabetic macroangiopathy (“diabetic foot“) are also divided into different stages, whereby, for example, an existing infection also plays a role here.

Bone necrosis is divided into seven stages according to the ARCO classification. Diagnostic criteria in particular are taken into account. Necrosis describes cell death as a reaction to damaging influences such as toxins, infections or undersupply.

A single cell or entire cell groups can be affected. Necroses are divided into the so-called “coagulation necroses” (coagulation necrosis) and “colliquation necroses” (liquefaction necrosis). Coagulation necrosis can occur in protein-rich tissues, whereby denaturation (destruction of the structure) of the proteins occurs.

Gangrene describes a special form of coagulation necrosis. This means necrosis is a kind of umbrella term for various necrotic processes. A gangrene is again divided into a dry and a moist gangrene.

While a dry Gangrene appears very sunken and dried out and is therefore also called “mummified” or leathery, a moist Gangrene is slightly liquefied, shiny, purulent and malodorous. The reason for this is the immigration and multiplication of bacteria, which liquefy the Gangrene through their metabolic products. Another special form is the so-called gas fire, in which an infection of the Gangrene with Clostridia (clostridium perfringens) leads to the formation of gaseous bacterial toxins.