Mechanisms of development of diabetes mellitus in children
Hyperglycemia develops due to a lack of insulin or with an excess of factors that oppose its activity.
Why is insulin so necessary?
In healthy people, the pancreas releases digestive enzymes and hormones - insulin and glucagon - into the bloodstream to control the amount of glucose (simple sugars from food) in the body. The release of insulin into the blood lowers the volume of glucose, allowing it to enter the cells where it is metabolized. When the amount of sugar in the blood is very low, the pancreas secretes glucagon to stimulate the release of glucose from the liver.
Immediately after a meal is consumed, glucose and amino acids are absorbed into the bloodstream, and the amount of sugar in the blood rises sharply. The β-cells of the pancreas receive a signal to release insulin into the bloodstream. Insulin rises to its peak volume 20 minutes after eating.
Insulin allows glucose to enter cells, especially muscles and liver cells. Here insulin and other hormones direct glucose to maintain energy or store it for future use. When insulin levels are high, the liver stops producing glucose and stores it in other forms until the body needs it again.
As the amount of glucose in the blood reaches its peak, the pancreas decreases the production of insulin (about 2-4 hours after a meal, the amount of sugar and insulin is low).
Where can a "breakdown" occur?
Several pathogenic events are involved in the development of the disease. They range from autoimmune damage to β-cells with further insulin deficiency, to abnormalities that cause resistance to its activity. The basis of metabolic disorders in diabetes is the insufficient effect of insulin on the target tissues.
Insufficient insulin activity occurs due to impaired secretion of this hormone and / or diminished tissue responses to insulin. Impaired insulin secretion and deviations in its activity are often combined in one patient, and it is not clear which defect, if only one, is the main cause of hyperglycemia.
Classification of diabetes mellitus
There are 3 types of disease.
Type 1 diabetes mellitus (T1DM)
Insulin-dependent diabetes is the most common type of illness in children. T1DM occurs when the body attacks the β-cells that make insulin, and as a result, it is not produced. Since there is no insulin, cells cannot absorb sugar from the bloodstream and convert it into energy for the body. This leads to an increase in blood sugar.
Type 2 diabetes mellitus (DM2)
This type rarely develops in a child. However, the number of children with T2DM has been on the rise lately. In this type of disorder, the pancreas is still producing insulin, but production will either be very slow to meet the needs, or the body does not respond to insulin properly, i.e. develops resistance to its action.
Prediabetes
This is a condition in which blood sugar is high but not sufficient to diagnose diabetes. If prediabetes is controlled, it can delay the development of type 1 and 2 diabetes in children.
Etiology
T1DM reasons
Most cases (95%) of T1DM are the result of environmental factors that interact with the patient's genetic susceptibility. This interaction leads to the development of an autoimmune disease that targets the insulin-producing cells of the pancreas. These cells are gradually destroyed, while insulin deficiency usually develops after 90% of their number is destroyed.
Genetic problems
There is clear evidence of the presence of a genetic component in the development of T1DM. In a monozygous (identical) twin, the lifetime risk of developing the disease increases to 60%, although diabetes mellitus develops in only 30% of cases within 10 years after the detection of the disease in the first twin. In contrast, a dizygotic (non-identical) twin has only an 8% risk, which is similar to that of other siblings.
The incidence of diabetes in children is 2 to 3% if the mother has the disease; this indicator increases if the father is sick. The likelihood increases to almost 30% if both parents have type 1 diabetes.
Some children cannot develop type 1 diabetes because they do not have a genetic marker that researchers have linked to type 1 diabetes. Scientists have found that T1DM can develop in people with a certain HLA complex. HLA is a human leukocyte antigen, and the function of antigens is to induce an immune response in the body. As a result, in children with T1DM, the immune system damages the insulin-producing β-cells. There are several HLA complexes that are associated with T1DM, and they are all on chromosome 6.
External factors
Infection and diet are the most common factors associated with T1DM.
Viral infections play an important role in the development of T1DM. They are thought to initiate or modify the autoimmune process. Cases of the direct toxic effect of the disease in congenital rubella have been identified. One survey found that enterovirus infection during pregnancy leads to an increased risk of T1DM in offspring. Paradoxically, the incidence of type 1 diabetes is higher in areas where the overall prevalence of infectious diseases is lower.
Diet also matters. Breastfed babies have a lower risk of developing type 1 diabetes, and there is a direct link between cow's milk consumption per capita and the incidence of diabetes. Some proteins in bovine milk (eg, bovine serum albumin) are similar to the β-cell antigen.
Nitrosamines, chemicals found in smoked foods and some water sources, are known to cause T1DM in animals; however, a definite association with the disease in humans has not been established.
The relationship between the increase in the incidence of T1DM in populations and the distance from the equator has been revealed. Reducing exposure to ultraviolet light and vitamin D levels, which are more common at higher latitudes, increases the risk of pathology.
Other reasons
Additional factors that increase the likelihood of developing T1DM include the following:
- congenital absence of the pancreas or insulin-producing cells;
- resection of the pancreas;
- damage to the pancreas (cystic fibrosis, chronic pancreatitis, thalassemia, hemochromatosis, hemolytic uremic syndrome);
- Wolfram syndrome;
- chromosomal abnormalities such as Down syndrome, Turner syndrome, Klinefelter syndrome, or Prader-Willi syndrome (the risk is about 1% in Down and Turner syndromes).
T2DM reasons
The causes of T2DM are complex. This condition, like T1DM, is the result of a combination of genetic factors and lifestyle.
Genetic changes
The risk of developing T2DM is increased if one or both parents have this disease.
It is difficult to determine which genes carry this risk. Studies have identified at least 150 DNA variants that are associated with the likelihood of T2DM. Most of these changes are common and are present in both diabetic patients and healthy people. Each person has some changes that increase the risk and others that reduce it. It is the combination of these changes that helps determine the likelihood of developing a disease in a person.
It is believed that genetic changes associated with T2DM change the time and location of gene activity (expression). These changes in expression affect genes involved in many aspects of T2DM, including β-cell development and function, insulin release and processing, and cell sensitivity to its effects.
Risk factors
The main risk factors for developing T2DM in young people are as follows:
- Obesity and lack of exercise are the factors most contributing to the development of insulin resistance.
- The presence of type 2 diabetes in relatives of the 1st and 2nd line.
- Age 12-16 years is the average age range for the onset of T2DM in young people. This period coincides with the relative insulin resistance that occurs during puberty.
- Too low or high birth weight.
- Gestational diabetes or T2DM in the mother.
- Artificial feeding during infancy.
- Maternal smoking increases the likelihood of developing diabetes and obesity in the offspring.
Smoking in teens also increases their own risk of developing diabetes. Insomnia and psychosocial stress are associated with an increased risk of childhood obesity and impaired glucose tolerance in adults.
The main symptoms of diabetes in children
T1DM symptoms
As diabetes progresses, symptoms continually increase, reflecting:
- decrease in the mass of β-cells;
- worsening insulinopenia (lack of insulin);
- progressive hyperglycemia.
Initially, when only the supply of insulin is limited, hyperglycemia sometimes occurs. When serum glucose exceeds the renal threshold, recurrent polyuria (increased urine production) or nocturia (predominance of nocturnal diuresis) begins. With further β-cell loss, chronic hyperglycemia causes more persistent diuresis, often with nocturnal enuresis, and polydipsia (insatiable thirst) becomes more evident. Female patients may develop fungal vaginitis due to chronic glucosuria (glucose in the urine).
Calories are lost in the urine (due to glucosuria), causing compensatory hyperphagia (overeating). If this hyperphagia does not keep pace with glucosuria, fat loss follows, accompanied by clinical weight loss and a decrease in subcutaneous fat stores. A healthy 10-year-old child consumes about 50% of the 2000 calories per day in the form of carbohydrates. When a child develops diabetes, the daily loss of water and glucose can be 5 liters and 250 g, respectively, which is 1000 calories or 50% of the average daily calorie intake. Despite the compensatory increase in food intake, the body is starving because unused calories are lost in the urine.
When your child does not have enough insulin to convert glucose into energy, he uses fat as an alternative. When fat is broken down, by-products, ketones, build up in the body. At this point, the child's condition quickly deteriorates, abdominal discomfort, nausea and vomiting occur, and a fruity smell is felt from the mouth.
T2DM symptoms
An illness can be suspected in a child when the classic symptoms appear:
- polyuria;
- polydipsia;
- hyperphagia;
- weight loss.
Other early signs of diabetes in children include:
- blurred vision;
- violation of the sensitivity of the lower extremities;
- fungal infections.
However, many T2DM patients are asymptomatic, the disease remains undetected for many years.
More often, pathology occurs in people who are overweight or obese. Patients with T2DM often show signs of insulin resistance such as hypertension, PCOS (polycystic ovary syndrome), or acanthosis nigricans (darkening and thickening of the skin).
Complications of diabetes mellitus
All complications of diabetes are associated with poor monitoring of blood glucose volume.
Diabetic coma
It is a life-threatening complication that causes loss of consciousness. The condition occurs with excessively high or low glucose levels (hyperglycemia and hypoglycemia, respectively).
When falling into a coma, a person cannot wake up or purposefully respond to sounds and other types of stimulation. If left untreated, the condition can be fatal.
Before coma develops, the patient usually has signs and symptoms of hyperglycemia or hypoglycemia.
Hyperglycemia symptoms:
- increased thirst;
- frequent urination;
- fatigue;
- nausea and vomiting;
- shortness of breath;
- abdominal pain;
- fruity odor from the mouth;
- dry mouth;
- cardiopalmus.
Symptoms of hypoglycemia:
- trembling and nervousness;
- anxiety;
- fatigue;
- weakness;
- increased sweating;
- hunger;
- nausea;
- dizziness;
- speech disorder;
- confusion of consciousness.
Target organ damage
High glucose levels can lead to other diseases of organs and systems.
Diabetic retinopathy
This is a complication of the organ of vision, which occurs due to damage to the blood vessels of the retina.
Diabetic retinopathy is sometimes asymptomatic, only minor vision problems may appear, but the condition can progress to blindness.
Any patient with uncontrolled diabetes is likely to develop this pathology.
Symptoms:
- spots or dark strings before the eyes;
- blurred vision;
- violation of color identification;
- blindness.
Diabetic retinopathy usually affects both eyes.
Diseases of the feet
There are two main foot problems affecting diabetic patients.
Diabetic neuropathy
Diabetes can damage nerves, making it difficult for patients to feel anything in their limbs.
In this condition, a person does not feel irritation on the leg or does not notice when the shoes begin to rub. Lack of feeling and awareness leads to an increased risk of blistering, sores, and cuts.
Peripheral vascular disorders
The disease causes changes in blood vessels, including arteries. Fat deposits block blood vessels outside the brain and heart. Basically, the vessels leading to and from the limbs are affected, reducing blood flow to them.
Reduced blood flow leads to pain, infection, and delayed wound healing. For severe infections, amputation may be required.
Symptoms of Diabetic Foot Problems
Manifestations of a diabetic foot:
- loss of sensitivity;
- numbness or tingling;
- painless blisters or other wounds;
- change in skin color;
- changes in skin temperature;
- red stripes;
- painful tingling sensation;
- fingertip staining;
- deformation of the foot.
If there is an infection in the foot ulcer, the symptoms are as follows:
- fever;
- chills;
- redness.
With such symptoms, you need to call an ambulance.
Cardiovascular disorders
Heart disease in diabetes is caused by high blood sugar levels. Over time, high glucose damages the arteries, making them stiff and hard. The accumulation of fat inside these blood vessels leads to the development of atherosclerosis. Ultimately, blood flow to the heart or brain can be blocked, leading to heart attack or stroke.
Diabetic nephropathy
Diabetic nephropathy is a disease of the kidneys in diabetes that interferes with their work to remove waste and excess fluid from the body.
The kidneys contain millions of tiny clusters of blood vessels (glomeruli) that filter waste from the blood. Severe damage to these blood vessels due to high glucose levels leads to diabetic nephropathy, decreased kidney function, and kidney failure.
Laboratory methods for confirming the diagnosis
If a child is suspected of having diabetes, the pediatrician will order some tests to diagnose the condition.
- Determination of blood sugar levels. This test is done to check the amount of glucose in your child's blood at any random time. If the test results show high blood sugar levels, the doctor may diagnose diabetes. But if the test results are normal, but the specialist still suspects diabetes, he will order additional tests to determine the amount of sugar in the blood.
- Glycated hemoglobin test (A1C). This test is done to determine your child's average blood sugar level over the past two or three months. The test measures the percentage of glucose associated with hemoglobin. If the A1C level is higher than 6.5 on two separate tests, this indicates that the child has diabetes.
- Fasting blood sugar test: the test involves taking a blood sample after a night's sleep on an empty stomach.
If the child is diagnosed with diabetes, a blood test for autoantibodies will be done to find out the type of diabetes.
Treatment approaches
Diet. What is a "grain" unit?
Adherence to your diet is an important component of diabetes management. Prior to the discovery of insulin, children with diabetes were kept alive by a diet strictly limited in carbohydrate intake. These measures have led to a long tradition of strict carbohydrate control.
To calculate the carbohydrate load in diabetes, the concept of "bread" unit (XE) is used:
1 XE = 12 g of digestible carbohydrates. This amount is contained in half a 1 cm thick piece of bread.
After consuming 1 XE, the amount of glucose in the blood increases by 2 mmol / l.
Carbohydrates should be at least 50 - 60% of the daily energy requirement, fats - 20% - 30% and proteins 15 - 20%. The daily caloric content of the diet is calculated by the formula: 1000+ (nx100), where n is the number of years of the child. During puberty, for boys, for every year after 12 years, 100 kcal is added, for girls - 100 kcal is subtracted. The regimen of food intake is 6 meals a day at the next distribution of daily calorie intake.
| Breakfast | 20 – 25 % |
| 2nd breakfast | 20 – 25 % |
| Dinner | 20 – 25 % |
| Afternoon snack | 5 – 10 % |
| Dinner | 10 – 15 % |
| 2nd dinner | 5 – 10% |
The dietitian should develop a diet plan for each child according to their individual needs and circumstances. It is necessary to regularly review and adjust the plan, taking into account the patient's height and lifestyle changes.
Movement is life
Patients with type 1 diabetes require daily exercise under glycemic control before starting exercise and hourly during exercise. If necessary, a carbohydrate subsidy. Preferred sports: tennis, athletics, dancing, skiing.
Under the influence of physical exertion, children not only increase muscle mass, improve coordination, endurance, emotional tone, but also utilize glucose by muscles without the participation of insulin. With T1DM in children, delayed hypoglycemia may develop, which occurs 12 hours or more after physical exertion, which dictates the need to determine glycemia within 24 hours from the start of training and reduce the insulin dose in the next 12 hours after intense exercise.
Treatment for type 1 diabetes
The treatment of T1DM in children requires an integrated approach with an emphasis on medical, dietary and psychosocial issues. Treatment strategies should be flexible to suit the individual needs of each patient and family.
A study on the control of diabetes and complications found that intensive insulin therapy, aimed at maintaining blood glucose concentrations as close to normal as possible, can delay the onset and slow the progression of complications of diabetes (retinopathy, nephropathy, neuropathy). Achieving this goal with intensive insulin therapy may increase the risk of hypoglycemia. The adverse effects of hypoglycemia in young children can be significant because the immature CNS is more susceptible to glycopenia.
The goals of therapy differ depending on the age of the patient. For children under 5 years of age, a suitable goal is to maintain a blood glucose concentration between 80 and 180 mg / dL. For school-aged children, an acceptable target range is 80 to 150 mg / dL. For teens, the target is 70 to 130 mg / dL.
There are many types of insulin, which vary in duration of action and time to maximum effect. These insulins can be used in different combinations, depending on the needs and goals of the individual patient.
- Fast-acting insulin: this type of insulin takes effect within 15 minutes and is taken right before meals. In a healthy person, the body releases insulin when they eat. This release of insulin during meals is called bolus secretion, which is mimicked by rapid-acting insulin.
- Short-acting insulin: takes effect within 30 minutes - 1 hour. It is also taken before meals, but lasts longer than fast-acting insulin. It is introduced 30 minutes - 1 hour before meals. This type of insulin also mimics bolus secretion.
- Intermediate insulin: the effect lasts 10-16 hours. It is usually taken twice a day and used to mimic basal secretion. Basal secretion is a small amount of insulin that is always in the blood (if there is no diabetes). In order to function effectively, the body needs this type of secretion, so T1DM patients must take insulin that mimics it.
- Long-acting insulin: like intermediate acting insulin, prolonged insulin reproduces basal secretion. The effect lasts 20-24 hours, so it is usually taken once a day. Some people may take this type of insulin twice a day for better blood sugar control.
- Mixed: combines two types of insulin - for example, fast and intermediate action. This will overlap the bolus and basal secretions.
The most commonly used regimen is multiple injections of fast-acting insulin given during meals in combination with prolonged basal insulin given at bedtime. After the total daily insulin dose has been determined, 30% to 50% is given as long-acting insulin, and the remainder is given as fast-acting insulin, divided according to the need for correcting high glucose and food intake.
Treatment for type 2 diabetes
T2DM is a progressive syndrome that gradually leads to absolute insulin deficiency throughout the patient's life. A systemic approach to the treatment of T2DM should be applied in accordance with the natural course of the disease, including the addition of insulin preparations. However, lifestyle changes (diet and exercise) are an integral part of the treatment regimen and consultation with a dietitian is usually necessary.
There is no specific diet or exercise regimen, but most experts recommend a low-calorie, low-fat diet and 30-60 minutes of physical activity at least 5 times a week. Screen time (watching TV and using a computer) should be limited to 1-2 hours a day. T2DM patients often come from a home environment with poor understanding of healthy eating habits.
Commonly observed behaviors include skipping meals, eating heavy snacks, and spending large amounts of time watching television, playing video games, and using the computer. Treatment in these cases is often difficult and ineffective if the whole family is hesitant to change their unhealthy lifestyle.
When lifestyle changes fail to normalize blood glucose levels, oral hypoglycemic medications (lowering blood glucose levels) are prescribed. Patients with markedly elevated glycated hemoglobin will require insulin treatment on a regimen similar to that used for T1DM. Once blood glucose is under control, most cases can be treated with oral hypoglycemic drugs and lifestyle changes, but some patients will still need insulin therapy.
First aid for coma
It is important to have your blood sugar measured if your child has any unusual symptoms so that the condition does not progress to coma. Diabetic comas are considered a medical emergency that requires immediate medical attention.
Treatment should be carried out in a hospital setting as quickly as possible and depends on the type of coma:
- hypoglycemic diabetic coma: the introduction of glucose and glucagon (a hormone that increases glucose levels);
- hyperglycemic diabetic coma: providing hydration and insulin administration.
Recovery is quick after starting treatment, but if the patient does not receive medical attention soon after entering a coma, long-term consequences can occur, such as the risk of permanent brain damage.
Coma can be fatal if left untreated.
Even if a diabetic coma does not occur, keeping blood sugar levels too low or too high for long can be very harmful.
The prognosis of diabetes in children. Benefits for children
The prognosis depends on the degree of diabetes compensation and the rate of development and progression of complications. Provided an optimally organized day and rest regimen, rational nutrition, insulin therapy, the prognosis is conditionally favorable. About 1/3 of patients die from end-stage (irreversible) renal failure within 15 - 20 years from the onset of the disease.
For children with diabetes, benefits from the state are provided, which will reduce the cost of treatment and rehabilitation of the patient. With type 1 diabetes, the child is assigned a disability.
People with diabetes are provided with:
- a voucher to a sanatorium or health camp with paid travel to the point for the child and his accompanying person;
- disability pension;
- special conditions for passing the exam, assistance with admission to an educational institution;
- the right to be diagnosed and treated in a foreign clinic;
- exemption from military service for male patients;
- tax exemption;
- cash allowance for the parents of a sick child under 14 years old.
Diabetes school
Often, specialists in polyclinics do not have time to explain all the features of pathology. In order to train a person to identify alarming symptoms in a timely manner and prevent the development of complications, diabetes schools are being organized in medical institutions. After completing survival training, the child will be able to adapt to the social environment so as not to feel sick.
If there is a diabetic child in the house
Living with diabetes isn't easy. Your child will need to adhere to a routine that includes monitoring blood sugar levels, timely insulin injections, consistent healthy food intake, and physical activity.
Here are some tips to tame illness and make life easier and better for your child and yourself.
- Educate your child about the importance of diabetes care. Help him understand the seriousness of the disease.
- Teach your child to choose healthy foods. Become a role model.
- Encourage physical activity: do the exercises together to help your child get used to it.
- As your child grows up, encourage him to take an active part in the treatment of the disease.
- Talk to the nurse at the schoolwhere the child is studying so that she can help check the child's blood sugar level and promptly administer insulin.
Prevention
Prevention consists in dynamic monitoring of children from families with a burdened history. These children should have their blood glucose levels checked regularly, and their general condition and other health parameters assessed. For patients, the most relevant is the prevention of exacerbations of diabetes, slowing its further progression, which is possible when attending a diabetes school.
The preventive measures are as follows.
- Following a balanced diet. Your child should eat foods that are low in fat, calories and high in fiber.
- Daily exercise for at least 30 minutes a day. This can be jogging, swimming, cycling.
- If the child is overweight, losing even 7% of their weight can reduce the risk of developing diabetes.
Conclusion
By following the doctor's instructions, your child can effectively manage diabetes. The only responsibility of parents is to offer the necessary support to the sick child. It is necessary to cultivate healthy lifestyle habits in him in order to maintain his well-being for life.
