Diabetes mellitus type 1

Diabetes mellitus type 1is an endocrine disease characterized by insufficient insulin production and elevated blood sugar levels. Due to prolonged hyperglycemia, patients suffer from thirst, lose weight and quickly tire. It is characterized by muscle and headaches, cramps, itchy skin, increased appetite, frequent urination, insomnia, hot flashes. The diagnosis includes a clinical interview, laboratory tests of blood and urine, which reveal hyperglycemia, lack of insulin, and metabolic disorders. Treatment is carried out with the help of insulin therapy, diet and physical exercises are prescribed.

Main information

The term "diabetes" comes from Greek and means "flowing, leaking", so the name of the disease describes one of its main symptoms - polyuria, the release of large amounts of urine. Type 1 diabetes is also called autoimmune, insulin-dependent and juvenile diabetes. The disease can occur at any age, but is more common in children and adolescents. In recent decades, an increase in epidemiological indicators has been observed. The prevalence of all forms of diabetes mellitus is 1-9%, the insulin-dependent variant of the pathology accounts for 5-10% of cases. The incidence depends on the ethnicity of the patients and is highest among Scandinavian peoples.

Causes of type 1 diabetes

Factors contributing to the development of the disease continue to be studied. It has already been established that type 1 diabetes occurs based on a combination of biological predisposition and external adverse influences. The most likely causes of pancreatic damage and reduced insulin production include:

• Heredity.The tendency to insulin-dependent diabetes is transmitted in a straight line - from parents to children. Several combinations of genes predisposing to the disease have been identified. They are most common among residents of Europe and North America. Having an affected parent increases the child's risk by 4-10% compared to the general population.
• Unknown external factors.There are certain environmental influences that provoke type 1 diabetes. This fact is confirmed by the fact that identical twins, who have exactly the same set of genes, get sick together only in 30-50% of cases. It was also found that people who migrated from an area of low incidence to an area of higher epidemiology were more likely to develop diabetes than those who refused to migrate.
• Virus infection.An autoimmune response to pancreatic cells can be triggered by a viral infection. Coxsackie and rubella viruses are the most likely to influence.
• Chemicals, drugs.The beta cells of the gland that produces insulin can be damaged by certain chemicals. Examples of such compounds are rat poison and medicine for cancer patients.

Pathogenesis

The pathology is based on insufficient production of the hormone insulin in the beta cells of the islets of Langerhans of the pancreas. Insulin-dependent tissues include liver, fat, and muscle. When insulin secretion decreases, they stop taking glucose from the blood. A state of hyperglycemia occurs - a key sign of diabetes mellitus. The blood thickens, blood circulation in the vessels is disturbed, which is manifested by deterioration of vision and trophic lesions of the limbs.

Insulin deficiency stimulates the breakdown of fats and proteins. They enter the bloodstream and are then metabolized by the liver into ketones, which become energy sources for non-insulin-dependent tissues, including brain tissue. When the concentration of blood sugar exceeds 7-10 mmol/l, the alternative pathway for the release of glucose is activated - through the kidneys. Glycosuria and polyuria develop, leading to an increased risk of body dehydration and electrolyte deficiency. To compensate for the loss of water, the feeling of thirst increases (polydipsia).

Classification

According to the recommendations of the World Health Organization, diabetes mellitus type I is divided into autoimmune (caused by the production of antibodies against the cells of the gland) and idiopathic (there are no organic changes in the gland, the causes of the pathology remain unknown). The development of the disease takes place in several stages:

1. Identifying a predisposition.Preventive examinations are carried out, the genetic burden is determined. Taking into account the average statistical indicators for the country, the level of the risk of developing the disease in the future is calculated.
2. Initial starting point.Autoimmune processes are activated and β-cells are damaged. Antibodies have already been produced, but insulin production remains normal.
3. Active chronic autoimmune insulitis.The antibody titer becomes high and the number of insulin-producing cells decreases. A high risk of developing diabetes in the next 5 years is determined.
4. Hyperglycemia after carbohydrate loading.A significant proportion of insulin-producing cells are destroyed. Hormone production decreases. Normal fasting glucose levels are maintained, but hyperglycemia is detected within 2 hours after a meal.
5. Clinical manifestation of the disease.Symptoms characteristic of diabetes mellitus appear. Hormonal secretion is sharply reduced, 80-90% of the cells of the gland are subject to destruction.
6. Absolute insulin deficiency.All cells responsible for insulin synthesis die. The hormone enters the body only in the form of a medicine.

Symptoms of type 1 diabetes

The main clinical signs of the disease are polyuria, polydipsia and weight loss. The urge to urinate becomes more frequent, the volume of daily urine reaches 3-4 liters, nighttime urination sometimes occurs. Patients experience thirst, dry mouth and drink up to 8-10 liters of water per day. Appetite increases, but body weight decreases by 5-12 kg in 2-3 months. You may also experience insomnia at night and sleepiness during the day, dizziness, irritability and fatigue. Patients experience constant fatigue and find it difficult to carry out their usual work.

Itching of the skin and mucous membranes, rashes and ulcers appear. The condition of hair and nails deteriorates, wounds and other skin lesions do not heal for a long time. Impaired blood flow in capillaries and vessels is called diabetic angiopathy. Capillary damage is manifested by reduced vision (diabetic retinopathy), reduced kidney function with edema, arterial hypertension (diabetic nephropathy), uneven redness of the cheeks and chin. In macroangiopathy, when veins and arteries are involved in the pathological process, atherosclerosis of the vessels of the heart and lower extremities begins to progress and gangrene develops.

Half of patients develop symptoms of diabetic neuropathy, which results from electrolyte imbalance, insufficient blood supply, and swelling of nerve tissue. The conductivity of nerve fibers deteriorates, convulsions are provoked. With peripheral neuropathy, patients complain of burning and pain in the legs, especially at night, a feeling of "pins and needles", numbness and increased sensitivity to touch. Autonomic neuropathy is characterized by disturbances in the functions of internal organs - symptoms of digestive disorders, bladder paresis, genitourinary infections, erectile dysfunction, angina pectoris appear. In focal neuropathy, pain with different localization and intensity is formed.

Complications

Prolonged disruption of carbohydrate metabolism can lead to diabetic ketoacidosis, a condition characterized by the accumulation of ketones and glucose in the plasma and increased acidity of the blood. It manifests acutely: appetite disappears, nausea and vomiting appear, abdominal pain, the smell of acetone in exhaled air. In the absence of medical assistance, confusion, coma and death occur. Patients with signs of ketoacidosis require emergency treatment. Other dangerous complications of diabetes include hyperosmolar coma, hypoglycemic coma (in case of improper insulin administration), "diabetic foot" with the risk of limb amputation, severe retinopathy with complete loss of vision.

Diagnosis

Patients are examined by an endocrinologist. Sufficient clinical criteria for the disease are polydipsia, polyuria, changes in weight and appetite - signs of hyperglycemia. During the examination, the doctor also clarifies the presence of hereditary burden. The presumptive diagnosis is confirmed by the results of laboratory tests of blood and urine. The detection of hyperglycemia allows to distinguish diabetes mellitus from psychogenic polydipsia, hyperparathyroidism, chronic renal failure and diabetes insipidus. At the second stage of the diagnosis, differentiation of different forms of diabetes is carried out. The complete laboratory examination includes the following studies:

• Glucose (blood).Determination of sugar is carried out three times: in the morning on an empty stomach, 2 hours after a carbohydrate load and before going to bed. Hyperglycemia is indicated by readings of 7 mmol/l on an empty stomach and 11. 1 mmol/l after taking a carbohydrate meal.
• Glucose (urine).Glycosuria indicates persistent and severe hyperglycemia. Normal values for this test (in mmol / l) are up to 1. 7, borderline - 1. 8-2. 7, pathological - more than 2. 8.
• Glycated hemoglobin.Unlike free glucose, which is not bound to proteins, the amount of glycosylated hemoglobin in the blood remains relatively constant throughout the day. The diagnosis of diabetes is confirmed at levels of 6. 5% and above.
• Hormonal studies.Insulin and C-peptide tests are done. The normal fasting blood concentration of immunoreactive insulin ranges from 6 to 12. 5 µU/ml. The C-peptide indicator allows you to assess the activity of beta cells and the volume of insulin production. The normal result is 0. 78-1. 89 μg / l, in diabetes mellitus the concentration of the marker is reduced.
• Protein metabolism.Creatinine and urea tests are done. The final data allow to clarify the functionality of the kidneys and the degree of change in protein metabolism. If the kidneys are damaged, the levels are higher than normal.
• Lipid metabolism.For early detection of ketoacidosis, the content of ketone bodies in the blood and urine is examined. To assess the risk of atherosclerosis, the level of cholesterol in the blood (total cholesterol, LDL, HDL) is determined.

Treatment of type 1 diabetes

The efforts of doctors are aimed at eliminating the clinical manifestations of diabetes, as well as preventing complications, teaching patients to independently maintain normoglycemia. Patients are accompanied by a multi-professional team of specialists, which includes endocrinologists, nutritionists and physical therapy instructors. Treatment includes counseling, medication, and educational sessions. The main methods include:

• Insulin therapy.The use of insulin preparations is necessary for maximally achievable compensation of metabolic disorders and prevention of hyperglycemia. Injections are vital. The mode of application is prepared individually.
• Diet.Patients are prescribed a low-carbohydrate diet, including a ketogenic diet (ketones serve as an energy source instead of glucose). The basis of the diet is vegetables, meat, fish and dairy products. Sources of complex carbohydrates - wholemeal bread, cereals - are allowed in moderation.
• Dosed individual physical activity.Physical activity is beneficial for most patients who do not have severe complications. Classes are individually selected by a physical therapy instructor and conducted systematically. The specialist determines the duration and intensity of training, taking into account the patient's general state of health and the level of diabetes compensation. Regular walks, athletics and sports games are prescribed. Strength sports and marathon running are contraindicated.
• Self-control training.The success of diabetes maintenance treatment largely depends on the patients' level of motivation. During special classes, they are told about the mechanisms of the disease, possible methods of compensation, complications, and the importance of regular monitoring of the amount of sugar and the use of insulin is emphasized. Patients acquire skills for self-administration of injections, selection of food products and preparation of menus.
• Prevention of complications.Medicines are used to improve the enzyme function of glandular cells. These include agents that promote tissue oxygenation and immunomodulatory drugs. Timely treatment of infections, hemodialysis and antidote therapy are carried out to remove compounds that accelerate the development of the pathology (thiazides, corticosteroids).

Among the experimental methods of treatment, it is worth noting the development of special DNA vaccines for the treatment of diabetes mellitus at an early stage of development. In patients receiving intramuscular injections for 12 weeks, levels of C-peptide, a marker of pancreatic islet cell activity, increased. Another line of research is transforming stem cells into glandular cells that produce insulin. Experiments conducted on rats gave positive results, but to use the method in clinical practice, evidence of the safety of the procedure is needed.

Prognosis and prevention

The insulin-dependent form of diabetes mellitus is a chronic disease, but proper maintenance therapy allows patients to maintain a high quality of life. Preventive measures have not yet been developed, as the exact causes of the disease have not been clarified. Currently, all people at risk are recommended to undergo annual examinations in order to detect the disease at an early stage and promptly start treatment. This measure allows you to slow down the process of formation of persistent hyperglycemia and minimizes the likelihood of complications.