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gangrene

What is gangrene?

Gangrene comes from the Greek and means "that which eats away". This name came about due to the external appearance of gangrene and the sometimes very rapid spread of it. Gangrene is tissue necrosis in which the skin dies and subsequently dissolves and changes.

Gangrene used to be called "gangrene". They are divided into dry burn, wet burn (infected gangrene) and gas burn (infection with clostridia). The most common cause of gangrene is a reduced blood flow to tissue, for example due to arterial disease, diabetes or frostbite.

Localizations

Gangrene on the tooth

Gangrene on, or rather in, the tooth is caused by inflammation of the tooth pulp. The tooth pulp is located inside the tooth and contains the nerves and blood vessels that supply the tooth. Bacterial or chemical factors can lead to inflammation of the pulp and swelling of it. Since the pulp is surrounded by hard material, the pressure cannot escape, which leads to severe pain. The pressure also closes the vessels and causes necrotic remodeling of the pulp tissue.

The substances released during inflammation, such as ammonia, can escape at the root of the tooth and cause an extremely unpleasant bad breath. In rare cases, the inflammation can spread to the jawbone, which can be very dangerous.

A tooth gangrene is treated by drilling open the tooth in order to release the pressure and to ensure rinsing (disinfection).

You might also be interested in the topic: Symptoms of root inflammation

Gangrene of the appendix

A gangrene of the appendix is actually a gangrenous appendix. Appendix or appendix is an appendage located on the appendix which tends to become inflamed. There is a naturally occurring bacterial flora in the large intestine. Either accidentally or through relocation of the appendix, for example through poorly digestible food or stool, the process can be infected by the intestinal bacteria.

This is followed by a strong swelling of the appendix, which in turn can cut off the blood supply. Depending on how strongly inflamed or how much the blood supply is blocked, appendicitis is divided into several stages. The last stage is also known as "appendicitis gangrenosa". The blood supply is completely suppressed and the intestinal cells die off. The appendix usually turns black-green in color and manifests itself as severe pain.

When the process is surgically removed, which is the only sensible therapy in this case, a bad smell and co-inflammation of the surrounding tissue are usually noticed.

Read more on the topic: Appendicitis

Gangrene of the gallbladder

Gallbladder gangrene is very similar to appendix gangrene. Inflammation of the gallbladder also results in an under-supply of blood with a subsequent necrotic change in the form of gangrene. In contrast to the appendix, gallstones in the gallbladder usually build up bile acid, which leads to irritation and inflammation. Bacteria migrate into the actually sterile wall of the gallbladder, which further intensifies the inflammation.

Due to the increased pressure and the additional swelling of the gallbladder wall, there is an insufficient supply of blood to it. In the most severe form of gallbladder inflammation, the cells subsequently die off and the cells undergo necrotic remodeling, which is then also referred to as gangrene. At this stage there is a high risk of the gallbladder bursting (perforation), which can lead to inflammation of the peritoneum and be very dangerous.

You might also be interested in the topic: Inflammation of the gallbladder

Fournier gangrene

Fournier gangrene or Fournier's gangrene is a special form of necrotizing fasciitis. This leads to a bacterial infection, which spreads along the fascia boxes. Fournier gangrene occurs in the genital, perineum or anal region and is a rapidly progressing disease. The skin dies (necroses) and becomes discolored.

Redness, itching, swelling, and severe pain are also symptoms. In addition, there is usually a high fever, increased heart rate and a poor general condition. Despite therapy, Fournier gangrene is associated with a mortality rate of 20-50%. Such gangrene is treated with a broad-acting antibiotic and surgical "debridement". This means that the necrotic skin areas are generously removed and, if necessary, covered with skin grafts at intervals.

Risk factors for Fournier gangrene are:

diabetes
weakened immune system
Smoke
chronic alcohol consumption
Obesity
the male gender

Read more on the subject at: Fournier gangrene

Gangrene on the foot

The foot is a very common site for gangrene. The reason for this is that these are caused by an insufficient supply of tissue with blood, including oxygen. Due to their great distance from the center of the body and their narrow vessels, feet have an increased risk of blood deficiency.

Common causes are:

arterial occlusive disease ("smoker's leg")
an arterial embolism (wandering blood clot)
a macroangiopathy ("diabetic foot")

All of these causes lead to a narrowing or occlusion of the supplying blood vessels (arteries) via various mechanisms. This can happen suddenly (for example due to an arterial embolism) or slowly (for example due to a diabetic foot). The foot is insufficiently supplied with oxygen, which leads to tissue death. The skin turns grayish-black and dries up, which is also known medically as "mummification" (dry gangrene). If bacteria also migrate, the gangrene liquefies and is referred to as moist. Moist gangrene also tend to have a very strong smell and are therefore usually noticed early. Once noticed, gangrene should be treated as soon as possible.

causes

The most common cause of gangrene is an insufficient blood flow in tissues remote from the body (peripheral), such as feet and fingers, caused by systemic factors. These are primarily diabetes, smoking and diseases of the cardiovascular system.

With gangrene of the internal organs, a spontaneous inflammation of the respective organ is usually responsible. The undersupply of blood leads to a lack of oxygen in the tissue, which in medicine is also referred to as "ischemia". It leads to over-acidification and swelling of the cells. The cell proteins perish (denature) and the tissue begins to rot.

Diabetes as a risk factor

In diabetes, there is an increased concentration of sugar in the blood due to a lack of insulin (hormone of the pancreas). If this is increased over a longer period of time, it can lead to a so-called saccharification (glycation) of the "bad" cholesterol (LDL) and an increased deposition of it on the vessel wall.

The lack of insulin leads to an increased breakdown of fat in the body, which leads to an increased concentration of fats in the blood. All of these factors lead to increasing damage to the vascular wall, which reduces its diameter and worsens blood flow. Medically, this is called "diabetic macroangiopathy" and can lead to what is known as a "diabetic foot".

Read more on the topic: Diabetic microangiopathy

Smoking as a risk factor

Smoking negatively affects the vascular system in several different ways. Nicotine affects the nervous system and promotes the release of the stress hormones adrenaline and noradrenaline from the adrenal gland. These narrow the blood vessels and thereby increase blood pressure.

The oxygen radicals contained in cigarette smoke, which get into the blood via the lungs, damage the vessel wall, which in the long term leads to a narrowing of it.

Furthermore, the cigarette smoke has an influence on the lipid metabolism and changes the blood consistency by making the blood "thicker" and more difficult to flow through narrow vessels. All these factors lead to a poor blood supply in the context of arteriosclerosis, which in the long term leads to a so-called “smoker's leg” and can manifest itself as gangrene.

You might also be interested in the topic: Peripheral arterial disease

diagnosis

Gangrene is usually a so-called clinical diagnosis. This means that medical professionals can make the diagnosis after a thorough inspection and physical examination. In most cases, gangrene is even a visual diagnosis, which means that only a quick look is necessary to be able to make a suspected diagnosis. In addition, a smear of gangrene is usually taken and microbiologically examined for bacteria.

Concomitant symptoms

Accompanying symptoms of gangrene are mainly pain and a foul-smelling, putrid odor. Outwardly, a gangrene appears as black-greenish discoloration, shrunken and sore. Gangrene can be either dry or wet. With a damp gangrene there is also a very foul-smelling, putrid, repulsive odor, which indicates an infection with bacteria and tends to spread quickly.

Pain occurs especially with gangrene of the internal organs and with suddenly occurring oxygen deficiency. In addition, there may be a pale coloration of the respective extremity and cold skin. Sensory disturbances and muscle weakness are also often found. The latter symptoms occur mainly in diabetics and smokers and have mostly been present for a long time and are therefore hardly noticed any more.

Pain

Whether and how severe pain occurs in gangrene primarily depends on how suddenly it occurs. Gangrene of the internal organs is usually always accompanied by severe, cramp-like pain. If these suddenly stop, the organ may have ruptured and an emergency room should be visited as soon as possible.

Gangrene of the skin, which is caused by a sudden lack of oxygen, is associated with very severe pain and is usually not overlooked for this reason. In the case of diabetics, small nerves can also be damaged in the long term, which can greatly reduce or even prevent the pain and lead to gangrene being overlooked.

Read more on the topic: Circulatory disorders

treatment

Gangrene should be treated as soon as possible. The earlier gangrene is discovered, the better the result of the therapy. One of the reasons for this is the invasion of bacteria, which can be prevented by rapid therapy. As part of the examination, the doctor will take a swab to test whether and, if so, which bacteria are present. However, since such a microbiological result usually takes about two days, broad-acting antibiotic therapy is started beforehand if a bacterial infection is suspected.

If possible, a so-called "necrectomy" is also performed. The dead tissue is surgically removed. If this is not possible because the infection has already spread too much or because the cause of the gangrene (e.g. reduced blood flow) cannot be treated, an amputation may be necessary. In rare cases, the infection can spread into the bloodstream, which requires inpatient treatment.

Duration of healing and prognosis

The most important principle in the treatment of gangrene is that it can only heal if the cause in question is eliminated. If this is the case, because, for example, a migrated blood clot (embolism) was responsible for it and this was removed, the healing time depends on how advanced the gangrene was. If this has been completely removed and any bacteria that may be present have been treated with antibiotics, nothing stands in the way of complete healing.

It is important to know that dead tissue that is present in gangrene cannot be healed. It is only possible to remove it. However, if there is a chronic (long-term) cause, such as a smoker's leg or diabetic foot, the prognosis depends heavily on the actual disease. In such cases, gangrene may not heal properly and may recur. For this reason, correct blood sugar control in diabetics and stopping consumption and adequate exercise in smokers is essential for the prognosis. Especially with smokers and diabetics, especially with repeated occurrence of gangrene, amputation cannot be avoided because of the lack of prospect of improvement.

What is the difference between gangrene and necrosis?

Gangrene and necrosis relate to one another in much the same way as an apple to fruit. Necrosis describes the death of cells as a reaction to damaging influences such as poisons, infections or insufficient supplies. This can affect a single cell or entire cell clusters. Necroses are divided into so-called coagulation necrosis (coagulation necrosis) and liquefaction necrosis (colliquation necrosis).

Coagulation necrosis can develop in protein-rich tissues, with denaturing (destruction of the structure) of the proteins. A gangrene describes a special form of coagulation necrosis, in which a necrotic remodeling occurs, especially due to an insufficient supply of oxygen.

A gangrene is in turn divided into a dry and a wet gangrene. While a dry gangrene appears very sunken and parched and is therefore also referred to as “mummified”, a wet gangrene is slightly liquefied, shiny, purulent and smelly. The reason is the immigration and multiplication of bacteria, which liquefy 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.

Further information

Further information on the subject can be found on the following pages: