Diabetic gangrene is the necrosis of a part of the body in diabetes mellitus. Distal parts of the lower extremities usually suffer. The main symptoms are pain, black (black-blue, dark purple) limb color, lack of sensitivity and blood supply in the affected area. With wet necrosis, suppuration, nausea, chills, hyperthermia are observed. The diagnosis is made on the basis of anamnesis and external examination data, MRI, ultrasound, radiography are prescribed to assess the condition of tissues and vessels, ankle-shoulder index is determined, neurological examination is performed. Depending on the prevalence and type of necrosis, conservative measures, necrectomy or amputation of a limb are carried out.
ICD 10
E10-E14.5
Meaning
Diabetic gangrene is a local necrosis of a part of the body of a living organism. Is the cause of disability. In the case of wet necrosis, it causes intoxication of the body by the products of tissue decay. Diabetic gangrene is a severe form of diabetic foot syndrome. About 35-40% of patients with diabetes mellitus (DM) are at risk of developing this pathology, the epidemiological indicator is 3.5-8.5%. With type 1 diabetes, the probability of gangrene increases sharply 7-10 years after the onset of the disease, with type 2 diabetes, the risk of this complication exists from the onset of the disease. Patients with type 2 diabetes suffer from gangrene 10 times more often than those with type 1 diabetes mellitus. 8-12% of patients with a confirmed diagnosis need limb amputation.
Causes
The key etiological factor is the severe course of diabetes mellitus. Violation of glucose metabolism causes vascular, neurological and osteoarticular changes that lead to the development of gangrene. Primary and secondary causes of diabetic limb necrosis include:
- Decompensation of the DM. Prolonged hyperglycemia underlies vascular and neurological disorders. Gangrene is formed against the background of insufficient blood flow, tissue hypoxia, decreased sensitivity.
- Deformities of the foot. Limited mobility of the joints, uneven distribution of the load on the foot, overload of its individual sections lead to a violation of the trophic tissues and deformation of the foot. Scuffs, cracks and ulcers appear, in the area of which areas of necrosis are subsequently formed.
- Immunodeficiency conditions. There is a decrease in the adaptive and protective mechanisms of the body. Patients become more vulnerable to accidental skin damage, infection of wounds.
- Concomitant diseases. Gangrene is more often diagnosed in patients with pathologies of the cardiovascular and urinary systems. The risk group includes elderly people with severe nephropathy, cardiac and venous insufficiency, and overweight.
- Social-economic factors. Often, complications of diabetes are caused by low compliance of patients – inconsistency of their behavior with the recommendations and prescriptions of an endocrinologist. Other factors are the unavailability of medical care and an antisocial lifestyle.
Pathogenesis
The mechanisms of gangrene development include peripheral neuropathy, angiopathy and deformation of the feet with the formation of high-pressure areas. The pathogenetic basis of gangrene is circulatory disorders. Hyperglycemia provokes structural and functional changes in large and small vessels. The capillary membrane thickens, delaminates, selective filtration and exchange diffusion of liquids are disrupted. Nutrients and oxygen are not supplied in the right amount, metabolic products accumulate in the tissues.
The formation of atherosclerotic plaques leads to narrowing or blocking of the lumen of the arteries of large and small caliber. Against this background, destructive changes are formed, necrotic processes are triggered. With a violation of nutrition and oxygen supply, cells die. If this process occurs gradually, the development of dry gangrene is likely – the tissues are dehydrated, mummified. The cause of wet gangrene is the death of cells in the process of rotting. The decomposition of tissues occurs under the influence of bacteria, there is an accumulation of pus and gases.
Symptoms
Dry gangrene occurs with a slowly forming circulatory disorder. A limited area of tissues is affected, the spread of necrosis is uncharacteristic. At the stage of ischemia, severe pain is felt below the level of blockage of the vessel. The skin turns pale, becomes marble-bluish. The temperature of the affected leg is reduced, there is a deterioration in sensitivity, tingling, itching, burning are possible. In healthy tissues bordering on the focus of necrosis, an inflammatory process develops with pronounced fullness. As a result, a demarcation line is formed – a border zone of acute inflammation.
Due to edema in the demarcation zone, pain syndrome persists for a long time. Other types of sensitivity in the underlying departments are completely lost. The affected area is black, dark blue or black-brown. Necrosis spreads from the periphery to the area with normal blood circulation, then the process stops. Necrotic tissues along the demarcation line soften and are replaced by granulation tissue, a scar is gradually formed. Sometimes there is spontaneous rejection of the dead part (spontaneous amputation). The dead tissues dry out, and do not disintegrate, so patients feel satisfactory, there are no signs of intoxication.
The first manifestations of wet gangrene are the pallor of the skin, the formation of spots and bubbles with sucrovichnoy fluid. The affected area is cold to the touch, sensitivity is absent or significantly reduced, veins are dilated. Edema progresses rapidly, the boundary between the affected and healthy areas is not defined, necrosis spreads in the proximal direction. Fabrics that have undergone rotting have a testy consistency and a fetid smell. Color – from gray to dark black. During palpation, a characteristic sound resembling a crunch or whistle is heard. Symptoms of general intoxication are increasing: high body temperature, lethargy, lethargy, headache, nausea, vomiting.
Complications
Despite the intensive development of diagnostic techniques in clinical endocrinology, approximately 47% of patients with diabetic gangrene are diagnosed at late stages. The most severe consequences are amputation of a limb and death from intoxication or sepsis. According to statistics, in economically developed countries, 6-8 amputations of the lower limb per 1,000 diabetic patients are performed every year. These figures do not take into account the amputation of part of the foot, so the real rates of complications are higher. About 12,000 operations are performed annually in the USA. 1.2% of patients with type I diabetes and 0.7% of patients with type II diabetes lose their feet. Amputations at the level of the lower leg and above are performed by 0.4% and 0.1% of patients, respectively.
Diagnostics
Diagnosis in the presence of a detailed clinical picture does not cause difficulties. Detection of diabetic gangrene in the early stages is a task for a polyprofessional team of specialists. People from the risk group require regular examinations by an endocrinologist, vascular surgeon, orthopedist. When signs of complications are detected, a full range of studies is carried out, which includes:
- Clinical survey, examination. There is a history of sensitivity disorders, swelling, pain, ulceration. On examination, a change in skin color from reddish to black, edema (with colliquation necrosis) or a decrease in the volume of the limb (with coagulation lesion), deformity of the foot, restriction of joint mobility is determined. When infected, pus is released from the wound. Various types of sensitivity are reduced or completely lost. Knee and Achilles reflexes are weakened. The ankle-shoulder index is less than 0.6-0.9.
- Laboratory tests. High levels of fasting glucose (more than 7 mmol/L) and glycosylated hemoglobin (more than 6.5%), elevated cholesterol, triglycerides, HDL and LDL are detected in the blood. In the urine – an increased concentration of glucose and ketone bodies. In case of purulent inflammation, bacterial seeding of the discharge onto the microflora is prescribed.
- Instrumental research. Common methods for assessing the safety of blood flow are ultrasound and radiopaque angiography of the vessels of the lower extremities. It is characterized by a decrease in capillary circulation, an increase in regional vascular resistance, damage to the vascular bed, impaired vascular patency below the occlusion area. Of the imaging diagnostic methods, CT and MRI of the foot are considered the most popular. There are signs of osteoarthropathy, osteoporosis, osteolysis in the metatarsal and tarsal areas, hyperostosis.
Treatment
Treatment of diabetic gangrene is carried out in a surgical hospital. Hypoglycemic drugs are replaced with insulin, dosages are adjusted to achieve a state of compensation for diabetes. They carry out general measures aimed at optimizing the work of blood vessels and the heart, eliminating intoxication, increasing the activity of the immune system. As part of systemic therapy, drugs that improve blood circulation (angioprotectors, microcirculation correctors), dissolving blood clots (direct-acting anticoagulants), relieving spasms (antispasmodics) are used.
To normalize blood pressure, diuretics, calcium antagonists, ACE inhibitors, beta-blockers are introduced into the treatment program. Upon admission, broad-spectrum antibiotics are prescribed, and then antibiotic therapy is corrected taking into account the sensitivity of the pathogen. Severe patients undergo blood transfusions, infusion of solutions to correct metabolic disorders, resuscitation measures. Crutches and wheelchairs are used to unload the affected foot.
With dry gangrene, mainly conservative management is indicated. Bandages are performed, dead tissues are removed in a dressing room when signs of separation appear. Local remedies are used to clean the wound surface, stimulate epithelialization. In case of wet gangrene due to intoxication and the danger of spreading necrosis, surgical treatment is carried out after the formation of the demarcation line. To localize the process, the limb is covered with ice bubbles, intra-arterial injections of antibiotics are performed.
Excision of dead tissues is usually carried out 1-3 days after admission. Necrotomy, necrectomy and amputation of a limb are possible. The purpose of necrotomy (tissue dissection) is to determine the boundaries of necrosis, reduce the intensity of the purulent-inflammatory process, and combat general intoxication. Necrectomy (removal of non-viable tissues) is performed with small areas of necrosis. Subsequently, bandages are prescribed, after cleansing the wound, according to indications, autodermoplasty and other techniques are used to close the defect. With extensive tissue necrosis and the threat of the process spreading to the overlying departments, amputation is required.
In the long-term period, in the absence of contraindications, planned interventions are carried out aimed at restoring blood circulation and preventing the recurrence of gangrene. Minimally invasive operations that do not require a long period of rehabilitation are mainly used. The type of procedure is determined individually. Stenting of peripheral arteries, endovascular dilation, arterialization of limb veins is possible.
Prognosis and prevention
Dry gangrene is considered a prognostically favorable variant of pathology, the degree of violation of limb support depends on the prevalence of the process. In persons with wet gangrene, the prognosis is less favorable both with respect to the preservation of limb functions and with respect to life. The cause of death may be a late request for medical help, the spread of the purulent-necrotic process to the proximal part of the limb, sepsis, decompensation of the functions of internal organs against the background of severe intoxication. Prevention of diabetic gangrene is based on the correct therapy of diabetes. It is important to strictly follow all doctor’s prescriptions, including taking medications, following a low-carb diet and a physical activity regime. It is worth giving up bad habits that contribute to the development of atherosclerosis (smoking, drinking alcohol and fatty foods), avoiding accidental wounds, choosing orthopedic shoes and keeping them clean inside, regularly performing hygienic foot care procedures.