Type 1 diabetes is an endocrine disease characterized by insufficient insulin production and an increase in blood glucose levels. Due to prolonged hyperglycemia, patients suffer from thirst, lose weight, and get tired quickly. Muscle and headache, cramps, itching, increased appetite, frequent urination, insomnia, hot flashes are characteristic. Diagnostics includes a clinical survey, laboratory tests of blood and urine, revealing hyperglycemia, lack of insulin, metabolic disorders. Treatment is carried out by the method of insulin therapy, a diet is prescribed, physical education classes.
ICD 10
E10 Insulin-dependent diabetes mellitus
The term “diabetes” comes from the Greek language and means “flowing, flowing”, so the name of the disease describes one of its key symptoms – polyuria, the excretion of a large amount of urine. Type 1 diabetes is also called autoimmune, insulin-dependent and juvenile. The disease can manifest itself at any age, but more often manifests in children and adolescents. In recent decades, there has been an increase in epidemiological indicators. The prevalence of all forms of diabetes mellitus is 1-9%, the share of the insulin-dependent variant of pathology accounts for 5-10% of cases. The incidence depends on the ethnicity of the patients, the highest among the Scandinavian peoples.
Causes
The factors contributing to the development of the disease continue to be investigated. To date, it has been established that type I diabetes mellitus occurs on the basis of a combination of biological predisposition and external adverse effects. The most likely causes of pancreatic damage, a decrease in 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. In the presence of a sick parent, the risk to the child increases by 4-10% compared to the general population.
- Unknown external factors. There are some environmental influences that provoke type 1 diabetes. This fact is confirmed by the fact that identical twins with exactly the same set of genes get sick together only in 30-50% of cases. It was also found that people who migrated from a territory with a low incidence to a territory with a higher epidemiology are more likely to suffer from diabetes than those who refused to migrate.
- Viral infection. An autoimmune response to pancreatic cells can be triggered by a viral infection. The most likely influence of Coxsackie and rubella viruses.
- Chemicals, medicines. Beta cells of the insulin-producing gland can be affected by certain chemicals. Examples of such compounds are rat poison and streptozocin, a drug 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 hepatic, fatty and muscular. When insulin secretion decreases, they stop taking glucose from the blood. There is a state of hyperglycemia – a key sign of diabetes mellitus. The blood thickens, the blood flow in the vessels is disrupted, which is manifested by deterioration of vision, trophic lesions of the extremities.
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 insulin-dependent tissues, including brain tissue. When the concentration of blood sugar exceeds 7-10 mmol / l, the alternate route of glucose excretion is activated – through the kidneys. Glucosuria and polyuria develop, as a result of which the risk of dehydration of the body and electrolyte deficiency increases. To compensate for the loss of water, the feeling of thirst (polydipsia) increases.
Classification
According to the recommendations of the World Health Organization, type I diabetes mellitus is divided into autoimmune (provoked by the production of antibodies to gland cells) and idiopathic (there are no organic changes in the gland, the causes of pathology remain unknown). The development of the disease occurs in several stages:
- Identification of predisposition. Preventive examinations are carried out, genetic burden is determined. Taking into account the average statistical indicators for the country, the level of risk of developing the disease in the future is calculated.
- Initial starting torque. Autoimmune processes are activated, beta cells are damaged. Antibodies are already being produced, but insulin production remains normal.
- Active chronic autoimmune insulitis. The antibody titer becomes high, and the number of insulin-producing cells decreases. A high risk of DM manifestation in the next 5 years is determined.
- Hyperglycemia after carbohydrate loading. A significant part of the insulin-producing cells undergoes destruction. Hormone production is decreasing. Normal fasting glucose levels are maintained, but hyperglycemia is detected after eating for 2 hours.
- Clinical manifestation of the disease. Symptoms characteristic of diabetes mellitus appear. Hormone secretion is sharply reduced, 80-90% of the gland cells are susceptible to destruction.
- Absolute insulin deficiency. All the cells responsible for the synthesis of insulin die. The hormone enters the body only in the form of a drug.
Symptoms of type 1 diabetes
The main clinical signs of the manifestation 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, sometimes night incontinence appears. Patients are thirsty, feel dry mouth, drink up to 8-10 liters of water per day. Appetite increases, but body weight decreases by 5-12 kg in 2-3 months. Additionally, there may be insomnia at night and drowsiness during the day, dizziness, irritability, fatigue. Patients feel constant fatigue, hardly perform the usual work.
There is itching of the skin and mucous membranes, rashes, ulceration. The condition of hair and nails worsens, wounds and other skin lesions do not heal for a long time. Violation of blood flow in capillaries and vessels is called diabetic angiopathy. Capillary damage is manifested by decreased vision (diabetic retinopathy), inhibition of kidney function with edema, arterial hypertension (diabetic nephropathy), uneven blush on the cheeks and chin. With macroangiopathy, when veins and arteries are involved in the pathological process, atherosclerosis of the vessels of the heart and lower extremities begins to progress, gangrene develops.
Half of the patients have symptoms of diabetic neuropathy, which is the result of electrolyte imbalance, insufficient blood supply and edema of the nervous tissue. The conductivity of nerve fibers worsens, convulsions are provoked. With peripheral neuropathy, patients complain of burning and painful phenomena in the legs, especially at night, a feeling of “goosebumps”, numbness, increased sensitivity to touch. Autonomic neuropathy is characterized by failures on the part of the functions of internal organs – symptoms of digestive disorders, bladder paresis, genitourinary infections, erectile dysfunction, angina pectoris occur. With focal neuropathy, pains of various localization and intensity are formed.
Complications
Prolonged violation of carbohydrate metabolism can lead to diabetic ketoacidosis – a condition characterized by the accumulation of ketones and glucose in the plasma, an increase in blood acidity. It proceeds acutely: appetite disappears, nausea and vomiting appear, abdominal pain, the smell of acetone in the exhaled air. In the absence of medical care, confusion, coma and death occur. Patients with signs of ketoacidosis need urgent treatment. Other dangerous complications of diabetes include hyperosmolar coma, hypoglycemic coma (with improper use of insulin), “diabetic foot” with the risk of limb amputation, severe retinopathy with complete loss of vision.
Diagnostics
The examination of patients is carried out by an endocrinologist. Sufficient clinical criteria for type 1 diabetes are polydipsia, polyuria, changes in weight and appetite – signs of hyperglycemia. During the survey, the doctor also clarifies the presence of hereditary burden. The alleged diagnosis is confirmed by the results of laboratory tests of blood and urine. The detection of hyperglycemia makes it possible to distinguish diabetes mellitus with psychogenic polydipsia, hyperparathyroidism, chronic renal failure, diabetes insipidus. At the second stage of diagnosis, differentiation of various forms of DM is carried out. A comprehensive laboratory examination includes the following analyses:
- Glucose (blood). Sugar determination is performed three times: in the morning on an empty stomach, 2 hours after loading with carbohydrates and before going to bed. Hyperglycemia is indicated by indicators from 7 mmol / l on an empty stomach and from 11.1 mmol / l after eating carbohydrate food.
- Glucose (urine). Glucosuria indicates persistent and pronounced hyperglycemia. Normal values for this test (in mmol/l) are up to 1.7, borderline values are 1.8-2.7, pathological values are more than 2.8.
- Glycated hemoglobin. Unlike free, protein-free glucose, the amount of glycosylated hemoglobin in the blood remains relatively constant throughout the day. The diagnosis of diabetes is confirmed at 6.5% or higher.
- Hormonal tests. Tests for insulin and C-peptide are being carried out. The normal concentration of immunoreactive insulin in the blood on an empty stomach is from 6 to 12.5 µed/ml. The C-peptide indicator allows you to evaluate the activity of beta cells, the volume of insulin production. The normal result is 0.78–1.89 mcg / l, with diabetes mellitus, the concentration of the marker is reduced.
- Protein metabolism. Creatinine and urea tests are performed. The final data make it possible to clarify the functional capabilities of the kidneys, the degree of change in protein metabolism. With kidney damage, the indicators are higher than normal.
- Lipid metabolism. For early detection of ketoacidosis, the content of ketone bodies in the bloodstream and urine is studied. In order to assess the risk of atherosclerosis, the level of blood cholesterol (total cholesterol, LDL, HDL) is determined.
Type 1 diabetes treatment
The efforts of doctors are aimed at eliminating the clinical manifestations of diabetes, as well as at preventing complications, teaching patients to independently maintain normoglycemia. Patients are accompanied by a polyprofessional team of specialists, which includes endocrinologists, nutritionists, physical therapy instructors. Treatment includes consultations, the use of medicines, and training sessions. The main methods include:
- Insulin therapy. The use of insulin preparations is necessary for the maximum achievable compensation of metabolic disorders, prevention of hyperglycemia. Injections are vital. The scheme of introduction is made individually.
- Diet. Patients are shown a low-carbohydrate, including ketogenic diet (ketones serve as an energy source instead of glucose). The basis of the diet consists of vegetables, meat, fish, dairy products. In moderation, sources of complex carbohydrates are allowed – whole grain bread, cereals.
- Dosed individual physical activity. Physical activity is useful for most patients who do not have severe complications. Classes are selected by the physical therapy instructor individually, conducted systematically. The specialist determines the duration and intensity of training, taking into account the general state of health of the patient, the level of compensation for diabetes. Regular walking, athletics, and sports games are assigned. Strength sports, marathon running are contraindicated.
- Self-control training. The success of supportive treatment for diabetes largely depends on the level of motivation of patients. In special classes, they are told about the mechanisms of the disease, about possible ways of compensation, complications, emphasize the importance of regular control of the amount of sugar and the use of insulin. Patients master the skill of self-injection, food selection, menu preparation.
- Prevention of complications. Medications that improve the enzyme function of glandular cells are used. These include agents that promote tissue oxygenation, immunomodulatory drugs. Timely treatment of infections, hemodialysis, antidote therapy is carried out to remove compounds that accelerate the development of pathology (thiazides, corticosteroids).
Among the experimental methods of treatment, it is worth noting the development of the BHT-3021 DNA vaccine. In patients who received intramuscular injections for 12 weeks, the level of C-peptide, a marker of activity of pancreatic islet cells, increased. Another area of research is the transformation of stem cells into glandular cells that produce insulin. The experiments conducted on rats gave a positive result, but for the use of 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 supportive 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 from risk groups are recommended to undergo annual examinations to detect the disease at an early stage and start treatment in a timely manner. This measure allows you to slow down the process of formation of persistent hyperglycemia, minimizes the likelihood of complications.