What is typical for diabetes insipidus tests. Diabetes insipidus. Diagnosis and differential diagnosis. Asymptomatic course of diabetes

Most of us are familiar with the main symptoms of diabetes - usually thirst and copious urination. Less well-known are weight gain, fatigue, dry skin and frequent pustular skin rashes. Often these signs are an indication for a laboratory examination.

But is the diagnosis of diabetes mellitus always so obvious: the differential diagnosis of the disease is of great interest to the scientific world.

It should be noted that in medicine there are two forms of "sugar" pathology: CD-1 (type 1, insulin-dependent) and CD-2 (type 2, insulin-independent).

• It is characterized by the almost complete absence of insulin in the body due to a violation of its synthesis in the beta cells of the pancreas that have undergone autoimmune destruction.
• the problem lies in the violation of the sensitivity of cell receptors: there is a hormone, but the body perceives it incorrectly.

How to distinguish types of pathology? The differential diagnosis of type 1 and type 2 diabetes is shown in the table below.

Table 1: Diagnosis of differential diabetes mellitus:

Important! All basic symptoms of the disease (polyuria, polydipsia, pruritus) are similar for IDDM and NIDDM.

Syndromes and diseases

Differential diagnosis of type 2 diabetes mellitus, like IDDM, is carried out according to the main syndromes.

In addition to diabetes, polyuria and polydipsia may be characteristic of:

• chronic kidney disease and chronic renal failure;
• primary hyperaldosteronism;
• hyperparathyroidism;
• neurogenic polydepsia.

According to the syndrome of hyperglycemia, differential diagnosis of type 1 and type 2 diabetes mellitus is carried out with:

• Itsenko-Cushing's disease/syndrome;
• steroid diabetes;
• acromegaly;
• hemochromatosis;
• pheochromocytoma;
• some diseases of the liver and pancreas;
• alimentary hyperglycemia.

With the development of glucosuria syndrome, the differential diagnosis of type 2 diabetes mellitus and IDDM is carried out with the following diseases:

• alimentary glucosuria;
• glucosuria in pregnancy;
• toxic lesions;
• kidney diabetes.

This is interesting. False-positive results in the study of urine for glucose can be observed when taking large doses of vitamin C, acetylsalicylic acid, cephalosporins.

Differential Diagnosis

diabetes insipidus

Differential diagnosis of diabetes and diabetes insipidus is of great interest to endocrinologists. Despite the fact that the symptoms of these pathologies are similar, their mechanism of development and pathogenesis are strikingly different.

Diabetes insipidus is associated with an acute shortage of the hypothalamic hormone vasopressin, which is responsible for maintaining normal water balance.

Secreted in the hypothalamus, vasopressin is transported to the pituitary gland, and then distributed with the bloodstream throughout the body, including the kidneys. At this level, it promotes the reabsorption of fluid in the nephron and its retention in the body.

Depending on the cause, diabetes insipidus can be central or nephrogenic (renal). The first often develops against the background of traumatic brain injuries, neoplasms of the hypothalamus or pituitary gland. The second is the result of various tubulopathies and impaired sensitivity to the hormone of the renal tissues.

Are both DM and the pathology under consideration clinically manifested by thirst and profuse urination? But what are the differences between them?

Table 2: Diabetes insipidus and diabetes mellitus - differential diagnosis:

sign	Diabetes
	Sugar	non-sugar
Thirst	Expressed moderately	intolerable
Volume of daily urine	Less than 3 l	Up to 15 l
The onset of the disease	gradual	Sudden, very acute
Enuresis	Absent	Available
hyperglycemia	+	—
Glucosuria	+	—
Relative density of urine	Increased	Very low
dry eating test	The patient's condition does not change	The patient's condition noticeably worsens, signs of dehydration appear.

Chronic kidney disease

In chronic renal failure at the stage of polyuria, patients often complain of frequent profuse urination, which may indicate the development of hyperglycemia. However, in this case, a differential diagnosis will help: type 2 diabetes mellitus and IDDM are also characterized by elevated blood sugar levels and glucosuria, and in CRF, signs of fluid retention in the body (edema), a decrease in rel. urine density.

Adrenal disorders and other endocrine disorders

Primary hyperaldosteronism (Conn's syndrome) is a clinical syndrome characterized by excessive production of the hormone aldosterone by the adrenal glands.

Its symptoms are quite typical and are manifested by three syndromes:

• defeat of the CCC;
• neuromuscular disorders;
• kidney dysfunction.

The defeat of the cardiovascular system, primarily represented by arterial hypertension. Neuromuscular syndrome is associated with hypokalemia and is manifested by bouts of muscle weakness, convulsions and short-term paralysis.

Nephrogenic syndrome is represented by:

• decrease in the contraceptive abilities of the kidneys;
• nocturia
• polyuria.

Unlike both forms of DM, the disease is not accompanied by disturbances in carbohydrate metabolism.

Itsenko-Cushing's disease/syndrome is another neuroendocrine disease with damage to the adrenal glands, which is involved in the differential diagnosis. It is accompanied by excessive secretion of glucocorticosteroids.

Clinically manifested by the following symptoms:

• obesity of a special type (excess weight is deposited mainly in the upper half of the body, the face becomes moon-shaped, and the cheeks are covered with a bright red blush);
• the appearance of pink or purple striae;
• excessive hair growth on the face and body (including in women);
• muscle hypotension;
• arterial hypertension;
• impaired insulin sensitivity, hyperglycemia;
• weakening of the immune system.

Gradually developing insulin resistance and signs of hyperglycemia may prompt the doctor to diagnose type 2 diabetes mellitus: the differential diagnosis in this case is carried out with an assessment of the additional symptoms described above.

In addition, the appearance of signs of hyperglycemia is possible with some other endocrine diseases (primary hyperthyroidism, pheochromocytoma), etc. Dif. Diagnosis of these diseases is based on advanced laboratory tests.

Pancreatitis and other gastrointestinal diseases

Chronic inflammatory damage to pancreatic tissues causes gradual death of functionally active cells with their sclerosis. Sooner or later, this leads to organ failure and the development of hyperglycemia.

It is possible to suspect the secondary nature of the syndrome on the basis of patient complaints (girdle pain in the epigastrium, radiating to the back, nausea, vomiting after eating fatty fried foods, various stool disorders), as well as laboratory and instrumental tests (increased levels of the alpha-amylase enzyme in the blood, ECHO signs of inflammation on ultrasound, etc.).

Note! Separately, it is necessary to highlight such a condition as alimentary hyperglycemia and glycosuria. They develop in response to the intake of excess carbohydrates in the body and, as a rule, persist for a short time.

Thus, the differential diagnosis of the main syndromes of DM is carried out with many diseases. A diagnosis based only on clinical data can be considered only preliminary: it must necessarily be based on data from a complete laboratory and instrumental examination.

Questions to the doctor

Asymptomatic course of diabetes

Hello! I am 45 years old, a woman, and there were no special complaints. Recently measured sugar - 8.3. I didn't donate blood on an empty stomach, maybe that's the reason.

A little later, I decided to take the test again. On an empty stomach from a vein, the result was also elevated - 7.4 mmol / l. Is it diabetes? But I have absolutely no symptoms.

Hello! Hyperglycemia in laboratory tests most often indicates the development of diabetes mellitus. Be sure to consult with an endocrinologist in person to decide whether to undergo an additional examination (first of all, I would advise you to donate blood for HbAc1, ultrasound of the pancreas).

Self-diagnosis

Good evening! Tell me if there are any reliable signs that will help determine if you have diabetes. I recently noticed that I began to eat a lot of sweets. It cannot be a symptom of a health problem.

Hello! Craving for sweets is not considered as a manifestation of DM. From the point of view of physiology, such a need may indicate a lack of energy, overwork, stress, hypoglycemia.

About SD, in turn, may indicate:

• dry mouth;
• strong thirst;
• frequent and profuse urination;
• weakness, decreased performance;
• sometimes - skin manifestations (severe dryness, pustular diseases).

Signs of diabetes in a child

With adults, everything is more or less clear. How to suspect diabetes in a child? I heard that in babies the disease is very difficult, up to coma and death.

Hello! Indeed, children are a special category of patients that require close attention from both medical professionals and parents.

The first thing that attracts attention in case of illness in childhood is thirst: the child begins to drink noticeably more, sometimes he can even wake up at night, asking for water.

The second most common "childish" symptom of diabetes is frequent urination and enuresis. Sticky urine stains can be seen on the potty or near the toilet, if the baby wears a diaper, due to the high sugar content in the urine, it can stick to the skin.

Then weight loss becomes noticeable: the baby quickly loses kilograms even despite a good appetite. In addition, there are signs of asthenia: the baby becomes lethargic, drowsy, rarely participates in games.

All this should alert attentive parents. Such symptoms require immediate examination and medical advice.

diabetes insipidus, otherwise referred to as diabetes, is a pathological process characterized by impaired reabsorption of fluid in the kidneys, as a result of which urine is not sufficiently concentrated, therefore, it is excreted in very large quantities in diluted form. Against this background, patients develop a constant feeling of thirst, indicating a significant loss of fluid by the body. If the loss of fluid by the body is not compensated sufficiently from the outside, then dehydration develops.

Diabetes insipidus develops as a result of a defect in the production of vasopressin, an antidiuretic hormone produced by the hypothalamus, or a decrease in the sensitivity of the kidney tissue to its effects. Diabetes insipidus belongs to a group of rare endocrine pathologies, which in 20% of cases develops as a complication after brain surgery. According to medical statistics, the development of the disease is not related to the sex and age of patients, but is more often recorded in people 20-40 years old.

Classification of diabetes insipidus

Depending on the level at which violations occur, there are two types of diabetes insipidus:

1. Central or hypothalamic diabetes insipidus- occurs as a result of a violation of the formation or release of antidiuretic hormone. It is further subdivided into idiopathic diabetes insipidus, which is based on a hereditary pathology characterized by low production of antidiuretic hormone, and symptomatic diabetes insipidus, which can occur against the background of other diseases, for example, with injuries and tumor processes of the brain, infectious inflammation of the meninges, etc.

2. Nephrogenic or renal diabetes insipidus- occurs due to a violation of the sensitivity of the renal tissues to the effects of vasopressin. This type of diabetes insipidus is much less common. In this case, either the inferiority of the structure of the nephrons, or the vasopressin resistance of the receptors of the renal tissue is noted. This type of diabetes insipidus can be congenital, or it can occur with drug-induced damage to kidney cells.

Some authors also point out gestagenic diabetes insipidus of pregnancy, the development of which is associated with increased activity of a special placental enzyme that destroys vasopressin. Young children may develop functional diabetes insipidus associated with the immaturity of the mechanism of urine concentration in the kidneys. In addition, against the background of the use of drugs from the group of diuretics, the development of iatrogenic diabetes insipidus.

Endocrinologists also distinguish primary polydipsia as one of the forms of diabetes insipidus, which manifests itself in the form of a pathological feeling of thirst (with damage or tumor processes in the thirst center in the hypothalamus) or a compulsive desire to drink (with neurosis, psychosis and schizophrenia). At the same time, due to an increase in fluid intake, the physiological production of vasopressin is suppressed and the clinical picture of diabetes insipidus develops.

Based on the clinical picture, diabetes insipidus is also classified according to severity without correction with drugs:

- mild degree the disease is characterized by daily urine output in the range of 6-8 liters;

At medium degree pathology, the amount of urine excreted per day is 8-14 liters;

For severe the daily volume of excreted urine is more than 14 liters.

During the period when the disease is corrected by drugs, three stages are distinguished in its course:

1. compensation stage, which is characterized by the absence of symptoms of thirst and an increase in the volume of urine excreted;

2. subcompensatory stage- with the periodic occurrence of a feeling of thirst and the presence of polyuria.

3. stage of decompensation, which is characterized by a constant feeling of thirst and polyuria, even during treatment.

Diabetes insipidus - causes and mechanism of development

Central diabetes insipidus can develop as a result of congenital genetic defects and pathologies of the brain. Acquired diabetes insipidus of the central type develops with tumor processes in the brain, as well as metastases resulting from tumor lesions of other organs, after trauma and infectious diseases that affect the brain. In addition, the disease can develop with ischemia and hypoxia of brain tissues as a result of vascular disorders. Idiopathic diabetes insipidus occurs with the spontaneous appearance of antibodies to cells that produce antidiuretic hormone, while an organic lesion of the hypothalamus is not detected.

Nephrogenic diabetes insipidus can also be congenital and acquired. Congenital forms of this type of diabetes insipidus develop with Wolfram syndrome and genetic defects in receptors that respond to vasopressin. Acquired forms of diabetes insipidus of the renal type can develop with chronic renal failure, amyloidosis of the kidneys, disorders of the metabolic processes of calcium and potassium in the body, and poisoning with drugs containing lithium.

Symptoms of diabetes insipidus

The two most telling symptoms of diabetes insipidus are polyuria(urination exceeding the daily norm) and polydipsia(drinking plenty of fluids). The volume of urine excreted per day in patients with diabetes insipidus can vary in the range of 4-30 liters, depending on the severity of the disease. At the same time, urine is practically colorless, has a low density and practically does not contain salt and other components. Because of the irresistible feeling of thirst, patients with diabetes insipidus consume a lot of fluids. The amount of fluid consumed by patients can range from 3 to 18 liters per day. Both one and the second signs entail sleep disturbance, neurosis, increased fatigue, and emotional imbalance.

Diabetes insipidus in children It is manifested most often by nighttime urinary incontinence, which is subsequently joined by growth retardation and puberty. Over time, there are structural changes in the organs of the urinary system, manifested in the form of expansion of the renal pelvis, ureters and bladder. Due to the consumption of significant volumes of fluid, the stomach also suffers, as its walls, as well as the surrounding tissues, are overstretched, which leads to prolapse of the stomach, dysfunction of the biliary tract and chronic irritable bowel syndrome.

When examining patients with diabetes insipidus, excessive dryness of the skin and mucous membranes is revealed. Patients complain of poor appetite, sudden weight loss, headaches, vomiting, and hypotension. One of the symptoms of diabetes insipidus in women is irregular menstruation. Diabetes insipidus in men is characterized by a decrease in sexual function.

The danger of diabetes insipidus lies in the possibility of developing dehydration, as a result of which persistent neurological disorders can develop. A similar complication occurs if the liquid. lost in the urine is not properly replenished from the outside.

What criteria are used to diagnose diabetes insipidus?

Diagnosis in the typical course of diabetes insipidus is quite simple. It relies on unquenchable thirst and an increased volume of daily urine, exceeding 3 liters per day in history. In a laboratory study, plasma hyperosmolarity and an increased level of sodium and calcium with a reduced level of potassium are important criteria. When examining urine, its hyperosmolarity and low density are also revealed.

The first stage of diagnosing diabetes insipidus is aimed at confirming the very fact of the presence of polyuria (increased amount of urine) with its low density. Usually, in diabetes insipidus, urine output exceeds 40 ml per kilogram of body weight with a relative density of urine less than 1005 g / l. If such urination is established, the second stage of diagnosis is carried out, which consists in performing a test with a dry diet. The test with dry food in the classic version according to Robertson involves the refusal of fluid intake (complete) and (preferably) the refusal of food in the first 8 hours of the test. Before the start of fluid and food restriction, the patient is determined by the osmolality of blood and urine, the level of sodium in the blood, the volume of urine excreted, body weight and blood pressure. After stopping the supply of food and water to the patient, this set of studies should be repeated every 1-2 hours, depending on how the patient feels. The test is terminated if during its course the patient has lost more than 3-5% of his weight, the patient's condition worsens, the sodium level and blood osmolality increase, and also when urine with an osmolality of more than 300 mOsm/l is obtained. In stable patients, such a test can be performed on an outpatient basis, while the patient should not drink for as long as he can stand according to his state of health. If a urine sample with an osmolality of 650 mOsm/L is obtained during fluid restriction, the diagnosis of diabetes insipidus may be ruled out.

Carrying out a test with a dry diet in patients suffering from diabetes insipidus does not lead to a significant increase in the osmolality of urine and the concentration of substances in it. During the test, in patients with diabetes insipidus, due to dehydration developing due to fluid loss, nausea and vomiting, convulsions, agitation, and headache appear. The temperature may rise.

When confirming the diagnosis of diabetes insipidus, a desmopressin test is performed - the administration of despopressin in patients with central diabetes insipidus causes a decrease in the amount of urine, and in patients with renal diabetes insipidus, the volume of urine does not decrease.

For differential diagnosis with diabetes, the level of glucose in blood taken on an empty stomach is determined. To clarify the cause of the development of diabetes insipidus, an x-ray is performed, an examination by an ophthalmologist and a psychoneurologist. If there is a suspicion of volumetric formations of the brain, magnetic resonance imaging is performed. The renal form of diabetes insipidus is diagnosed by ultrasound and computed tomography of the kidneys. If in doubt, a nephrologist is consulted and a kidney biopsy is performed.

How to treat diabetes insipidus?

After the diagnosis is made and the form of diabetes insipidus is established, treatment begins with the elimination of the cause that caused it, i.e. they remove tumors, eliminate the consequences of craniocerebral injuries, treat major diseases, etc.

For replacement of antidiuretic hormone in all forms of diabetes insipidus prescribe its synthetic analogue - desmopressin, which is applied orally by instillation into the nose. Central diabetes insipidus involves the use of chlorpropamide, carbamazepine and other drugs that stimulate the production of vasopressin.

An integral part of therapy are activities that normalize the water-salt balance, which include the infusion of large volumes of saline solutions. To reduce the excretion of urine, hypothiazide is prescribed.

Diet for diabetes insipidus involves reducing the load on the kidneys, therefore, includes products containing a minimum of protein and a sufficient amount of fats and carbohydrates. Patients with diabetes insipidus are recommended frequent fractional meals, which include a lot of vegetables and fruits. To quench your thirst, instead of water, it is preferable to use juices, compotes, fruit drinks.

Idiopathic form of diabetes insipidus does not pose a threat to life, but cases of complete recovery are extremely rare. Gestational and iatrogenic diabetes insipidus are more transient in nature, and most often end in a complete cure. Proper use of substitution therapy allows patients to maintain their ability to work. One of the most unfavorable prognostic forms of diabetes insipidus is renal diabetes insipidus in children.

• Analyzes in St. Petersburg

  One of the most important stages of the diagnostic process is the performance of laboratory tests. Most often, patients have to perform a blood test and a urine test, but other biological materials are often the object of laboratory research.

• Endocrinologist's consultation

  Specialists of the North-Western Center of Endocrinology diagnose and treat diseases of the endocrine system. The endocrinologists of the center in their work are based on the recommendations of the European Association of Endocrinologists and the American Association of Clinical Endocrinologists. Modern diagnostic and therapeutic technologies provide optimal treatment results.

Not many people know that in addition to the usual type 1 and type 2 diabetes, there is also diabetes insipidus. This is a disease of the endocrine glands, it is a syndrome of the hypothalamic-pituitary system. Therefore, such a disease really has nothing to do with diabetes, except for the name and constant thirst.

In diabetes insipidus, there is a partial or complete deficiency of the antidiuretic hormone vasopressin. It overcomes osmotic pressure and stores and then distributes fluid throughout the body.

So, the hormone provides the necessary amount of water that allows the kidneys to function normally. Therefore, vasopressin is necessary for natural homeostasis, because it ensures its normal operation even with a lack of moisture in the body.

In critical situations, for example, during dehydration, the brain receives a signal that regulates the functioning of organs. This contributes to the fact that fluid loss is reduced by reducing the flow of saliva and urine.

So, diabetes insipidus differs from diabetes in that during its course, the blood glucose indicator remains normal, but both diseases have a common symptom - polydipsia (strong thirst). Therefore, diabetes insipidus, which is characterized by the reabsorption of fluid from the tubules of the kidneys, received this name.

The course of ND is often acute. It is considered a disease of the young, so the age category of patients is up to 25 years. Moreover, a violation of the endocrine glands can occur in both women and men.

Diabetes insipidus: types

There is central and nephrogenic diabetes insipidus. CND, in turn, is divided into 2 types:

1. functional;
2. organic.

The functional type is categorized as an idiopathic form. The factors influencing the appearance of this species are not fully established, but many doctors believe that heredity plays a significant role in the development of the disease. Also, the reasons lie in a partial violation of the synthesis of the hormone neurophysin or vasopressin.

The organic form of the disease appears after various injuries, surgery and other injuries.

Nephrogenic diabetes insipidus develops when the natural functioning of the kidneys is disrupted. In some cases, there is a failure in the osmotic pressure of the renal tubules, in other situations, the susceptibility of the tubules to vasopressin decreases.

There is also such a form as psychogenic polydipsia. It can be triggered by drug abuse or PP is one of the manifestations of schizophrenia.

They also distinguish such rare types of ND as the gestagenic type and transient polyuria. In the first case, the placental enzyme is very active, which has a negative effect on the antidiuretic hormone.

Transient form of diabetes develops before the age of 1 year.

This occurs when the kidneys are underdeveloped, when the enzymes involved in metabolic processes begin to behave more actively.

Causes and symptoms of the disease

Sugar level

There are many factors that lead to the development of diabetes insipidus:

• tumor formations;
• chronic and acute infections (postpartum sepsis, influenza, syphilis, typhoid, scarlet fever, etc.);
• radiation therapy;
• nephritis;
• damage to blood vessels and parts of the brain;
• brain injury or surgery;
• amyloidosis;
• granulomatosis;
• hemoblastosis.

Autoimmune diseases and psychogenic disorders also contribute to the appearance of ND. And in the idiopathic form of the disease, the cause of the occurrence is the sharp appearance of antibodies against hormone-producing cells.

The clinical picture of diabetes insipidus is varied, ranging from headache to dehydration in the absence of adequate fluid intake. Therefore, in addition to screening, various tests for diabetes insipidus are performed.

The main signs of the disease include:

1. malfunctions in the digestive tract - constipation, gastritis, colitis, poor appetite;
2. strong thirst;
3. sexual dysfunction;
4. mental disorders - poor sleep, irritability, headache, fatigue;
5. frequent urination with copious amounts of fluid (6-15 liters);
6. drying of mucous membranes and skin;
7. visual impairment in diabetes;
8. weight loss
9. anorexia;
10. asthenic syndrome.

Often, diabetes insipidus is accompanied by increased internal pressure and decreased sweating. Moreover, if the patient does not drink enough water, then his condition will deteriorate greatly. As a result, the patient may develop such manifestations as blood clots, vomiting, nausea, tachycardia, fever, and a collapse occurs against the background of dehydration. In women with ND, the menstrual cycle is disrupted, and men have poor potency.

In children, the course of the disease can lead to a slowdown in sexual and physical development.

Diagnostics

To detect the presence of ND, a three-stage diagnostic examination is carried out:

• detection of hypotonic polyuria (urinalysis, Zimnitsky test, biochemical blood test);
• functional tests (desmopressin test, dry eating);
• detection of the causes that provoked the development of the disease (MRI).

First stage

Initially, if diabetes insipidus is suspected, a study is performed to determine the density of urine. Indeed, with the disease, the functioning of the kidneys worsens, as a result, the urine density is less than 1005 g / l.

To find out the level of density during the day, a study is being carried out according to Zimnitsky. This analysis is done every three hours for 24 hours. During this period, 8 urine samples are taken.

Normally, the results are deciphered as follows: the amount of the daily norm of urine should not exceed 3 liters, its density is 1003-1030, while the ratio of night and day diuresis is 1: 2, and excreted and drunk - 50-80-100%. The osmolarity of urine is 300 mosm/kg.

Also, to diagnose ND, a biochemical blood test is performed. In this case, the osmolarity of the blood is calculated. In the presence of a high concentration of salts in the plasma of more than 292 mosm / l and an excessive sodium content (from 145 nmol / l), diabetes insipidus is diagnosed.

Blood is taken from a vein on an empty stomach. Before the procedure (6-12 hours) you can drink only water. As a rule, the results of the tests need to wait one day.

In addition, in a biochemical blood test, such quantities are examined as:

1. glucose;
2. potassium and sodium;
3. total protein, including hemoglobin;
4. ionized calcium;
5. creatinine;
6. parathormone;
7. aldosterone.

The normal blood sugar level is up to 5.5 mmol / l. However, with ND, glucose concentrations often do not increase. But its fluctuations can be observed with strong emotional or physical stress, diseases of the pancreas, pheochromocytoma, and chronic liver and kidney failure. A decrease in sugar concentration occurs with violations in the functioning of the endocrine glands, starvation, tumors, and in case of severe intoxication.

Potassium and sodium are chemical elements that endow cell membranes with electrical properties. The normal content of potassium is 3.5 - 5.5 mmol / l. If its value is too high, then this indicates liver and adrenal insufficiency, cell damage and dehydration. A low potassium level is noted with starvation, kidney problems, an excess of certain hormones, dehydration, and cystic fibrosis.

The norm of sodium in the blood stream is from 136 to 145 mmol / l. Hypernatremia occurs with excessive salt intake, malfunctions in the water-salt balance, hyperfunction of the adrenal cortex. And hyponatremia occurs with the use of a large volume of fluid and in the case of pathologies of the kidneys and adrenal glands.

An analysis for total protein allows you to determine the level of albumin and globulins. The normal rate of total protein in the blood for adults is 64-83 g / l.

Of no small importance in the diagnosis of diabetes insipidus is glycosylated hemoglobin. Ac1 shows the average blood glucose over 12 weeks.

Hemoglobin is a substance present in red blood cells that delivers oxygen to all organs and systems. In people who do not suffer from diabetes, glycosylated hemoglobin in the blood does not exceed 4-6%, which is also characteristic of diabetes insipidus. Thus, elevated Ac1 values ​​make it possible to differentiate these diseases.

However, fluctuations in hemoglobin levels can occur with anemia, the use of nutritional supplements, the intake of vitamins E, C, and an excess of cholesterol. Moreover, glycosylated hemoglobin may have different indicators in diseases of the liver and kidneys.

The level of ionized calcium is an indicator responsible for mineral metabolism. Its average values ​​range from 1.05 to 1.37 mmol / l.

Also, tests for diabetes insipidus involve a blood test for aldosterone content. Deficiency of this hormone often indicates the presence of diabetes insipidus.

An increased level of creatinine and parathyroid hormone can also indicate the presence of the disease.

Second phase

At this stage, it is necessary to draw up a protocol for a dry diet test. The dehydration phase includes:

• blood sampling to check osmolality and sodium levels;
• taking urine to determine its quantity and osmolality;
• weighing the patient;
• measurement of pulse and blood pressure.

However, in hypernatremia, such tests are contraindicated.

It is worth noting that during the test you can not eat fast carbohydrate food with. Preference should be given to fish, lean meat, boiled eggs, grain bread.

The dry eating test is stopped if: the osmolality and sodium level exceed the norm, there is unbearable thirst and there is a weight loss of more than 5%.

The desmopressin test is done to distinguish between central and nephrogenic diabetes insipidus. It is based on testing the patient's sensitivity to desmopressin. In other words, the functional activity of V2 receptors is tested. The study is done after a dry diet test with the highest exposure to endogenous AVP.

Before testing, the patient must urinate. Then he is injected with desmopressin, while he can drink and eat, but in moderation. After 2-4 hours, urine is taken to determine its osmolality and volume.

Normally, the test results are 750 mOsm / kg.

With NDI, the values ​​rise to 300 mOsm/kg, and in the case of CND after dehydration, they are 300, and desmopressin - 750 mOsm/kg.

Third stage

An MRI is often done to detect diabetes insipidus. In a healthy person, the pituitary gland shows clear differences between the anterior and posterior lobes. Moreover, the latter on the T1 image has a hyperintense signal. This is due to the presence in it of secretory granules containing phospholipids and AVP.

In the presence of CND, the signal emitted by the neurohypophysis is absent. This is due to a failure in the synthesis and transport and storage of neurosecretory granules.

Also, with diabetes insipidus, a neuropsychiatric, ophthalmological and x-ray examination can be performed. And in the renal form of the disease, ultrasound and CT of the kidneys are done.

The leading method of therapy for NND is the use of synthetic analogues of vasopressin (Desmopressin, Chlorpropamide, Adiuretin, Minirin). In the renal form, diuretics and NSAIDs are prescribed.

Either type involves an infusion treatment based on the administration of a saline solution. This is necessary to correct the water-salt metabolism.

Of no small importance is the observance of a certain diet, including limited intake of salt (4-5 g) and proteins (up to 70 g). These requirements correspond to the diet number 15, 10 and 7.

What tests should be taken if diabetes insipidus is suspected is described in the video in this article.

RCHD (Republican Center for Health Development of the Ministry of Health of the Republic of Kazakhstan)
Version: Clinical Protocols of the Ministry of Health of the Republic of Kazakhstan - 2013

Diabetes insipidus (E23.2)

Endocrinology

general information

Short description

Approved

minutes of the meeting of the Expert Commission

on Health Development of the Ministry of Health of the Republic of Kazakhstan

diabetes insipidus(ND) (lat. Diabetes insipidus) - a disease caused by a violation of the synthesis, secretion or action of vasopressin, manifested by the excretion of a large amount of urine with a low relative density (hypotonic polyuria), dehydration and thirst.
Epidemiology . The prevalence of ND in different populations varies from 0.004% to 0.01%. There is a worldwide trend towards an increase in the prevalence of ND, in particular, due to its central form, which is associated with an increase in the number of surgical interventions performed on the brain, as well as the number of traumatic brain injuries, in which the incidence of ND is about 30%. It is believed that ND affects both women and men equally often. The peak incidence occurs at the age of 20-30 years.

Protocol name:diabetes insipidus

Code (codes) according to ICD-10:
E23.2 - Diabetes insipidus

Protocol development date: April 2013

Abbreviations used in the protocol:
ND - diabetes insipidus
PP - primary polydipsia
MRI - magnetic resonance imaging
BP - blood pressure
DM - diabetes mellitus
Ultrasound - ultrasonography
GIT - gastrointestinal tract
NSAIDs - non-steroidal anti-inflammatory drugs
CMV - cytomegalovirus

Patient category: men and women aged 20 to 30 years, a history of trauma, neurosurgical interventions, tumors (craniopharyngoma, germinoma, glioma, etc.), infections (congenital CMV infection, toxoplasmosis, encephalitis, meningitis).

Protocol Users: district therapist, endocrinologist at a polyclinic or hospital, neurosurgeon at a hospital, traumatologist at a hospital, district pediatrician.

Classification

Clinical classification:
The most common are:
1. Central (hypothalamic, pituitary), caused by a violation of the synthesis and secretion of vasopressin.
2. Nephrogenic (renal, vasopressin-resistant), characterized by resistance of the kidneys to the action of vasopressin.
3. Primary polydipsia: a disorder in which pathological thirst (dipsogenic polydipsia) or a compulsive desire to drink (psychogenic polydipsia) and the associated excess water intake suppress the physiological secretion of vasopressin, ultimately leading to the characteristic symptoms of diabetes insipidus, while dehydration of the body produces vasopressin is being restored.

Other rare types of diabetes insipidus are also distinguished:
1. Gestagen, associated with increased activity of the placental enzyme - arginine aminopeptidase, which destroys vasopressin. After childbirth, the situation is normalized.
2. Functional: occurs in children of the first year of life and is due to the immaturity of the concentration mechanism of the kidneys and increased activity of type 5 phosphodiesterase, which leads to rapid deactivation of the vasopressin receptor and a short duration of vasopressin action.
3. Iatrogenic: the use of diuretics.

Classification of ND according to the severity of the course:
1. mild form - urine output up to 6-8 l / day without treatment;
2. medium - urine output up to 8-14 l / day without treatment;
3. severe - urine output more than 14 l / day without treatment.

Classification of ND according to the degree of compensation:
1. compensation - in the treatment of thirst and polyuria do not bother;
2. subcompensation - during the treatment there are episodes of thirst and polyuria during the day;
3. decompensation - thirst and polyuria persist.

Diagnostics

The list of basic and additional diagnostic measures:
Diagnostic measures before planned hospitalization:
- general urine analysis;
- biochemical blood test (potassium, sodium, total calcium, ionized calcium, glucose, total protein, urea, creatinine, blood osmolality);
- assessment of diuresis (>40 ml/kg/day, >2 l/m2/day, urine osmolality, relative density).

The main diagnostic measures:
- Dry food test (dehydration test);
- Desmopressin test;
- MRI of the hypothalamic-pituitary zone

Additional diagnostic measures:
- Ultrasound of the kidneys;
- Dynamic tests of the state of kidney function

Diagnostic criteria:
Complaints and anamnesis:
The main manifestations of ND are severe polyuria (urine excretion of more than 2 l / m2 per day or 40 ml / kg per day in older children and adults), polydipsia (3-18 l / day) and associated sleep disorders. A preference for plain cold/ice-cold water is characteristic. There may be dryness of the skin and mucous membranes, a decrease in salivation and sweating. Appetite is usually reduced. The severity of symptoms depends on the degree of neurosecretory insufficiency. With a partial deficiency of vasopressin, clinical symptoms may not be so clear and manifest themselves in conditions of drinking deprivation or excessive fluid loss. When taking an anamnesis, it is necessary to clarify the duration and persistence of symptoms in patients, the presence of symptoms of polydipsia, polyuria, diabetes in relatives, the presence of a history of injuries, neurosurgical interventions, tumors (craniopharyngioma, germinoma, glioma, etc.), infections (congenital CMV infection , toxoplasmosis, encephalitis, meningitis).
In newborns and infants, the clinical picture of the disease differs significantly from that in adults, since they cannot express their desire for increased fluid intake, which makes timely diagnosis difficult and can lead to the development of irreversible brain damage. Such patients may experience weight loss, dry and pale skin, lack of tears and sweating, and fever. They may prefer water to breast milk, and sometimes the disease becomes symptomatic only after the baby is weaned. Urinary osmolality is low and rarely exceeds 150-200 mosmol/kg, but polyuria occurs only if the child has increased fluid intake. In children of this early age, hypernatremia and hyperosmolality of the blood with convulsions and coma very often and rapidly develop.
In older children, thirst and polyuria may come to the fore in clinical symptoms, with inadequate fluid intake, episodes of hypernatremia occur, which can progress to coma and convulsions. Children do not grow well and gain weight, they often have vomiting when eating, lack of appetite, hypotonic conditions, constipation, and mental retardation are observed. Explicit hypertonic dehydration occurs only in cases of lack of access to fluid.

Physical examination:
On examination, symptoms of dehydration can be detected: dry skin and mucous membranes. Systolic blood pressure is normal or slightly low, diastolic blood pressure is elevated.

Laboratory research:
According to the general analysis of urine - it is discolored, does not contain any pathological elements, with a low relative density (1.000-1.005).
To determine the concentration ability of the kidneys, a test according to Zimnitsky is carried out. If in any portion the specific gravity of urine is higher than 1.010, then the diagnosis of ND can be excluded, but it should be remembered that the presence of sugar and protein in the urine increases the specific gravity of the urine.
Plasma hyperosmolality is more than 300 mosmol/kg. Normal plasma osmolality is 280-290 mosmol/kg.
Hypoosmolality of urine (less than 300 mosmol/kg).
Hypernatremia (more than 155 meq / l).
In the central form of ND, there is a decrease in the level of vasopressin in the blood serum, and in the nephrogenic form, it is normal or slightly elevated.
Dehydration test(test with dry food). Dehydration test protocol according to G.I. Robertson (2001).
Dehydration phase:
- take blood for osmolality and sodium (1)
- collect urine for determination of volume and osmolality (2)
- measure the patient's weight (3)
- control of blood pressure and pulse (4)
In the future, at regular intervals, depending on the patient's condition, after 1 or 2 hours, repeat steps 1-4.
The patient is not allowed to drink, preferably also food restriction, at least during the first 8 hours of the test; When feeding, food should not contain a lot of water and easily digestible carbohydrates; boiled eggs, grain bread, lean meats, fish are preferred.
The test is terminated when:
- loss of more than 5% of body weight
- unbearable thirst
- objectively serious condition of the patient
- an increase in sodium and blood osmolality above the normal range.

Desmopressin test. The test is carried out immediately after the end of the dehydration test, when the maximum possibility of secretion/action of endogenous vasopressin has been reached. The patient is given 0.1 mg of desmopressin tablets under the tongue until completely absorbed or 10 mcg intranasally as a spray. Urinary osmolality is measured before taking desmopressin and 2 and 4 hours after. During the test, the patient is allowed to drink, but not more than 1.5 times the volume of urine excreted on the dehydration test.
Interpretation of the results of the test with desmopressin: In normal or primary polydipsia, urine concentration is above 600-700 mosmol/kg, blood osmolality and sodium remain within normal values, the state of health does not change significantly. Desmopressin practically does not increase the osmolality of urine, since the maximum level of its concentration has already been reached.
With central ND, urine osmolality during dehydration does not exceed blood osmolality and remains at a level of less than 300 mosmol/kg, blood osmolality and sodium increase, severe thirst, dry mucous membranes, increase or decrease in blood pressure, tachycardia are noted. With the introduction of desmopressin, the osmolality of urine increases by more than 50%. In nephrogenic ND, blood osmolality and sodium increase, urine osmolality is less than 300 mosmol/kg, as in central ND, but after the use of desmopressin, urine osmolality practically does not increase (up to 50% increase).
The interpretation of the test results is summarized in tab. .


Instrumental research:
Central ND is considered a marker of the pathology of the hypothalamic-pituitary region. MRI of the brain is the method of choice in the diagnosis of diseases of the hypothalamic-pituitary region. In central ND, this method has several advantages over CT and other imaging modalities.
MRI of the brain is prescribed to identify the causes of central ND (tumors, infiltrative diseases, granulomatous diseases of the hypothalamus and pituitary gland, etc. In nephrogenic diabetes insipidus: dynamic tests of the state of kidney function and ultrasound of the kidneys. In the absence of pathological changes according to MRI, this study is recommended in dynamics, since it is not uncommon for central ND to appear several years before a tumor is detected

Indications for expert advice:
If you suspect the presence of pathological changes in the hypothalamic-pituitary region, consultations of a neurosurgeon and an ophthalmologist are indicated. If a pathology of the urinary system is detected - a urologist, and if a psychogenic variant of polydipsia is confirmed, a referral to a consultation with a psychiatrist or neuropsychiatrist is necessary.

Differential Diagnosis

It is carried out between the three main conditions accompanied by hypotonic polyuria: central ND, nephrogenic ND and primary polydipsia. Differential diagnosis is based on 3 main stages.

Treatment abroad

Get treatment in Korea, Israel, Germany, USA

Get advice on medical tourism

Treatment

Treatment goals:
Reducing the severity of thirst and polyuria to such an extent that would allow the patient to lead a normal life.

Treatment tactics:
Central ND.
Desmopressin remains the most preferred drug. Most patients benefit from desmopressin tablets (0.1 and 0.2 mg), although many patients continue to be successfully treated with desmopressin intranasal spray. In view of individual pharmacokinetic characteristics, it is extremely important to determine the duration of action of a single dose of the drug individually for each patient.
Therapy with desmopressin in the form of tablets is prescribed at an initial dose of 0.1 mg 2-3 times a day orally 30-40 minutes before meals or 2 hours after meals. Average doses of the drug vary from 0.1 mg to 1.6 mg per day. Simultaneous food intake can reduce the degree of absorption from the gastrointestinal tract by 40%. With intranasal use, the initial dose is 10 mcg. When sprayed, the spray is distributed over the anterior surface of the nasal mucosa, which ensures a longer concentration of the drug in the blood. The need for the drug varies from 10 to 40 mcg per day.
The main goal of treatment with desmopressin is to select the minimum effective dose of the drug to stop thirst and polyuria. The obligatory increase in the relative density of urine should not be considered as the goal of therapy, especially in each of the Zimnitsky urinalysis samples, since not all patients with central ND against the background of clinical compensation of the disease in these analyzes achieve normal indicators of concentrated kidney function (physiological variability of urine concentration during the day, concomitant pathology of the kidneys, etc.).
Diabetes insipidus with inadequate thirst.
When the functional state of the thirst center changes in the direction of lowering the threshold of sensitivity, hyperdipsia, patients are predisposed to the development of such a complication of desmopressin therapy as water intoxication, which is a potentially life-threatening condition. Such patients are periodically advised to skip doses of the drug to release the delayed excess fluid or fixed fluid intake.
The state of adipsia in central ND may be manifested by alternating episodes of hypo- and hypernatremia. Such patients are managed with a fixed daily volume of fluid intake or with recommendations for fluid intake according to the volume of urine excreted + 200-300 ml of fluid additionally. Patients with impaired sensation of thirst require a special dynamic monitoring of the condition with monthly, and in some cases more often, determination of osmolality and blood sodium.

Central ND after surgery on the hypothalamus or pituitary gland and after head trauma.
The disease in 75% of cases has a transient, and in 3-5% - a three-phase course (phase I (5-7 days) - central ND, phase II (7-10 days) - syndrome of inadequate vasopressin secretion, phase III - permanent central ND ). Desmopresiin is prescribed in the presence of symptoms of diabetes insipidus (polydipsia, polyuria, hypernatremia, blood hyperosmolality) at a dose of 0.05-0.1 mg 2-3 times a day. Every 1-3 days, the need to take the drug is assessed: the next dose is skipped, the resumption of symptoms of diabetes insipidus is controlled.
Nephrogenic ND.
Thiazide diuretics and a low sodium diet are given to reduce symptomatic polyuria. The antidiuretic effect in this case is due to a decrease in the volume of extracellular fluid, a decrease in glomerular filtration rate, an increase in the reabsorption of water and sodium from primary urine in the proximal nephron tubules, and a decrease in the amount of fluid entering the collecting ducts. However, studies demonstrate that thiazide diuretics can increase the number of aquoporin-2 molecules on the membranes of nephron tubular epithelial cells, independently of vasopressin. Against the background of taking thiazide diuretics, it is desirable to compensate for the loss of potassium by increasing its intake or prescribing potassium-sparing diuretics.
When prescribing indomethacin, additional very beneficial effects develop, however, NSAIDs can provoke the development of duodenal ulcers and gastrointestinal bleeding.

Non-drug treatment:
With central ND with normal function of the thirst center - a free drinking regimen, a normal diet. In the presence of violations of the function of the center of thirst: - fixed fluid intake. With nephrogenic ND - salt restriction, the use of foods rich in potassium.

Medical treatment:
Minirin tablets 100, 200 mcg
Minirin, oral lyophilisate 60, 120, 240 mcg
Precynex nasal spray 10mcg/dose
Triampur-compositum, tablets 25/12.5 mg
Indomethacin - enteric-coated tablets 25 mg

Other types of treatment: -

Surgical intervention: with neoplasms of the hypothalamic-pituitary region.

Preventive actions: not known

Further management: outpatient observation

Indicators of treatment efficacy and safety of diagnostic and treatment methods described in the protocol: decreased thirst and polyuria.

1. List of references: 1. Guidelines, ed. Dedova I.I., Melnichenko G.A. "Central diabetes insipidus: differential diagnosis and treatment", Moscow, 2010, 36 p. 2. Melnichenko G.A., V.S. Pronin, Romantsova T.I. and others - "Clinic and diagnosis of hypothalamic-pituitary diseases", Moscow, 2005, 104 p. 3. Endocrinology: national guidelines, ed. Dedova I.I., Melnichenko G.A., Moscow, GEOTAR-Media, 2008, 1072 pp. 4. Pigarova E.A. - Diabetes insipidus: epidemiology, clinical symptoms, approaches to treatment, - "Doctor.ru", No. 6, part II, 2009. 5. Practical endocrinology / ed. Melnichenko G.A.-Moscow, "Practical Medicine", 2009, 352 p. Ed. Dedova I.I., Melnichenko G.A., Moscow, "ReadElsiver", 2010, 472 pp.

Information

List of developers:
1. Danyarova L.B. - Candidate of Medical Sciences, Head of the Endocrinology Department of the Research Institute of Cardiology and Internal Diseases, endocrinologist of the highest category.
2. Shiman Zh.Zh. - Junior Researcher of the Endocrinology Department of the Research Institute of Cardiology and Internal Diseases, endocrinologist.

Indication of no conflict of interest: absent.

Reviewers: Erdesova K.E. - candidate of medical sciences, professor, internship department of KazNMU.

Indication of the conditions for revising the protocol: The protocol is reviewed at least once every 5 years, or upon receipt of new data on the diagnosis and treatment of the relevant disease, condition or syndrome.

Attached files

Attention!

• By self-medicating, you can cause irreparable harm to your health.
• The information posted on the MedElement website and in the mobile applications "MedElement (MedElement)", "Lekar Pro", "Dariger Pro", "Diseases: a therapist's guide" cannot and should not replace an in-person consultation with a doctor. Be sure to contact medical facilities if you have any diseases or symptoms that bother you.
• The choice of drugs and their dosage should be discussed with a specialist. Only a doctor can prescribe the right medicine and its dosage, taking into account the disease and the condition of the patient's body.
• The MedElement website and mobile applications "MedElement (MedElement)", "Lekar Pro", "Dariger Pro", "Diseases: Therapist's Handbook" are exclusively information and reference resources. The information posted on this site should not be used to arbitrarily change the doctor's prescriptions.
• The editors of MedElement are not responsible for any damage to health or material damage resulting from the use of this site.