Diabetic nephropathy: classification by stages, symptoms, diagnosis, treatment, prevention

Among all the complications that diabetes threatens a person, diabetic nephropathy takes a leading place. The first changes in the kidneys appear already in the first years after the disease with diabetes, and the final stage - chronic renal failure( CRF).But careful compliance with preventive measures, timely diagnosis and adequate treatment help to delay the development of this disease as much as possible.

Diabetic nephropathy

Diabetic nephropathy is not one independent disease. This term unites a whole series of various problems, the essence of which is reduced to one - this is the defeat of renal vessels against the background of chronic diabetes mellitus.

In the group of diabetic nephropathy, the most common findings are:

• arteriosclerosis of the renal artery;
• diabetic glomerulosclerosis;
• fat deposits in the renal tubules;
• pyelonephritis;
• necrosis of the renal tubules, etc.

The ICD-10 code( the official International Classification of Diseases of the 10th revision), which has been in effect since 1909, uses 2 ciphers of this syndrome. And in various medical sources, patient records and reference books, you can find both options. This is E.10-14.2( Diabetes mellitus with kidney damage) and N08.3( Glomerular lesions in diabetes mellitus).

Most often, various disorders of the kidney function are recorded in type 1 diabetes, that is, insulin-dependent. Nephropathy occurs in 40-50% of diabetic patients and is recognized as the leading cause of death from complications in this group. In people suffering from type 2 pathology( insulin independent), nephropathy is fixed only in 15-30% of cases.

Causes of the development of the disease

Disturbance of the full functioning of the kidneys is one of the earliest consequences of diabetes mellitus. After all, it is on the kidneys that the main job is to cleanse blood of excess impurities and toxins.

When the level of glucose jumps in the blood of a diabetic, it acts on internal organs as a most dangerous toxin. Kidneys are finding it increasingly difficult to cope with their filtration problem. As a result, the influx of blood weakens, it accumulates sodium ions, which provoke a narrowing of the lumen of the kidney vessels. The pressure in them increases( hypertension), the kidneys begin to break down, which causes an even greater increase in pressure.

But, despite this vicious circle, kidney damage does not develop in all patients with diabetes.

Therefore, doctors distinguish 3 basic theories, which call the causes of development of renal ailments.

1. Genetic. One of the first reasons why a person falls ill with diabetes is called hereditary predisposition. The same mechanism is also attributed to nephropathy. Once a person develops diabetes, mysterious genetic mechanisms accelerate the development of vascular damage in the kidneys.
2. Hemodynamic. With diabetes, there is always a violation of the kidney circulation( the same hypertension).As a result, a large number of albumin proteins appears in the urine, the vessels under this pressure are destroyed, and the damaged sites are tightened by scar tissue( sclerosis).
3. Exchange. This theory assigns the main destructive role of increased glucose in the blood. From the impact of the "sweet" toxin all the vessels in the body( including the kidneys) suffer. Violated vascular blood flow, normal metabolic processes change, fat is stored in the vessels, which leads to nephropathy.

Classification of

Today, doctors in their work use the generally accepted classification for the stages of diabetic nephropathy according to Mogensen( developed in 1983):

But often in the reference literature there is also a division of diabetic nephropathy into stages based on changes in the kidneys. Here the following stages of the disease are distinguished:

1. Hyperfiltration. At this time, the blood flow in the renal glomeruli is accelerated( they are the main filter), the volume of urine increases, the organs themselves increase slightly in size. The stage lasts till 5 years.
2. Microalbuminuria. This is a slight increase in the level of protein albumens in urine( 30-300 mg / day), which conventional laboratory methods can not yet ascertain. If you timely diagnose these changes and organize treatment, the stage can last about 10 years.
3. Proteinuria( in another - macroalbuminuria).Here the blood filtration rate through the kidneys drops sharply, often renal arterial blood pressure( BP) jumps. The level of albumin in the urine at this stage can be from 200 to more than 2000 mg / day. This phase is diagnosed in the 10-15th year from the onset of the disease.
4. Severe nephropathy. GFR decreases even more, the vessels are covered by sclerotic changes. Diagnosed 15-20 years after the first changes in the kidney tissue.
5. Chronic renal failure. Appears after 20-25 years of life with diabetes.

Symptoms of

The first three stages of the Mogensen pathology( or periods of hyperfiltration and microalbuminuria) are called preclinical pathologies. At this time, the external symptoms are completely absent, the volume of urine is normal. Only in some cases, patients can notice a periodic increase in pressure at the end of the microalbuminuria stage.

At this time, only special tests for the quantitative determination of albumin in the urine of a diabetic patient can diagnose the disease.

The stage of proteinuria already has specific external signs:

• regular blood pressure jumps;
• patients complain of swelling( first swelling of the face and legs, then water accumulates in the body cavities);
• the weight drops sharply and appetite decreases( the body starts to spend protein stores to make up for the shortage);
• severe weakness, drowsiness;Thirst and nausea.

Diagnosis

Diagnosis of diabetic kidney damage is based on two main indicators. This is the history of the patient-diabetic( type of diabetes, how much the disease lasts, etc.) and the indicators of laboratory research methods.

At the preclinical stage of vascular renal disease development the main method is the quantitative determination of albumin in the urine. For analysis, either the total volume of urine per day, or the morning( i.e., night portion) is taken.

The albumin values ​​are classified as follows:

Another important diagnostic method is the detection of functional renal reserve( increased GFR in response to external stimulation, for example, dopamine administration, protein loading, etc.).The norm is considered to increase the level of GFR by 10% after the procedure.

The norm of the GFR index itself is ≥90 ml / min / 1.73 m 2.If this figure falls below, it indicates a decrease in kidney function.

Additional diagnostic procedures are also used:

• Reberg's test( definition of GFR);
• general analysis of blood and urine;
• kidney ultrasound with doppler( to determine the rate of blood flow in the vessels);
• kidney biopsy( for individual indications).

Treatment of

In the early stages, the main task in the treatment of diabetic nephropathy is to maintain an adequate level of glucose and treat arterial hypertension. When the stage of proteinuria develops, all medical measures should be directed to slowing down the decrease in kidney function and the appearance of CRF.

Drugs

The following drugs are used:

• ACE inhibitors - angiotensin converting enzyme, for pressure correction( Enalapril, Captopril, Fosinopril, etc.);
• preparations for the correction of hyperlipidemia, that is, elevated levels of fats in the blood( "Simvastatin" and other statins);
• diuretics( "Indapamide", "Furosemide");
• iron preparations for correction of anemia, etc.

Diet

A special low-protein diet is recommended already in the preclinical phase of diabetic nephropathy - with hyperfiltration of kidneys and microalbuminuria. During this period, it is necessary to reduce the "portion" of animal proteins in the daily diet to 15-18% of the total caloric value. This is 1 g per 1 kg of the body weight of a diabetic patient. The daily amount of salt should also be sharply reduced - to 3-5 g. It is important to limit the use of liquid to reduce swelling.

If the stage of proteinuria has developed, special nutrition is already becoming a full-fledged therapeutic method. The diet turns into a low protein - 0.7 g protein per 1 kg. The amount of salt consumed should be reduced to the maximum, up to 2-2.5 g per day. This will prevent strong swelling and reduce pressure.

In some cases, patients with diabetic nephropathy are prescribed ketone analogues of amino acids to exclude the splitting of the body's proteins from their own stores.

Hemodialysis and peritoneal dialysis

Artificial blood purification using the method of hemodialysis( "artificial kidney") and dialysis is usually performed in the late stages of nephropathy, when the native kidneys can no longer cope with the filtration. Sometimes hemodialysis is prescribed and at earlier stages, when diabetic nephropathy is already diagnosed, and organs need to be supported.

In hemodialysis, a catheter is inserted into the vein of the patient, connected to a hemodializator - a filtering device. And the whole system cleans the blood of toxins instead of the kidney for 4-5 hours.

How often are needed the blood cleansing procedures, solves only the doctor on the basis of the analyzes and the condition of the patient-diabetic. If the nephropathy has not yet passed into chronic renal failure, it is possible to connect an "artificial kidney" once a week. When the kidney function is already running out, hemodialysis is done three times a week. Peritoneal dialysis can be done daily.

Artificial blood purification for nephropathy is necessary when the GFR falls to 15 ml / min / 1.73 m2 and an abnormally high level of potassium( greater than 6.5 mmol / l) is recorded below. And also if there is a risk of pulmonary edema due to accumulated water, as well as all the signs of protein-energy deficiency.

Prevention

For diabetic patients, the prevention of nephropathy should include several main points:

• support in the blood of a safe level of sugar( regulate physical activity, avoid stress and constantly measure glucose level);
• proper nutrition( a diet with a reduced percentage of proteins and carbohydrates, refusal of cigarettes and alcohol);
• control of the ratio of lipids in the blood;
• monitoring the level of blood pressure( if it jumps above 140/90 mm Hg, it is urgent to take action).

All prevention measures must be agreed with the attending physician. Therapeutic diet should also be carried out under the strict supervision of the endocrinologist and nephrologist.

Diabetic Nephropathy and Diabetes

Treatment of diabetic nephropathy can not be separated from the treatment of the cause - diabetes itself. These two processes should be run in parallel and adjusted in accordance with the results of the patient's diabetic analysis and the stage of the disease.

The main tasks for diabetes, and kidney damage are the same - round the clock monitoring of glucose and blood pressure. The main non-medicamentous agents are the same at all stages of diabetes. This control over the level of weight, diet, reducing the number of stresses, rejection of bad habits, regular exercise.

The situation with taking medications is somewhat more complicated. In the early stages of diabetes and nephropathy, the main group of drugs is for pressure correction. Here you need to choose drugs that are safe in patients with kidney problems, which are allowed in other complications of diabetes, which have cardioprotective and non-protective properties. This is the majority of ACE inhibitors.

When tests already show proteinuria, in the treatment of diabetes it is necessary to take into account the decreased renal function and severe hypertension. Special restrictions apply to diabetics with type 2 pathology: for them, the list of approved oral hypoglycemic agents( PSSC) is sharply reduced, which must be taken continuously. The most safe drugs remain "Glikvidon", "Gliclazide", "Repaglinide."If GFR drops to 30 ml / min or less with nephropathy, patients need to be transferred to insulin administration.

There are also special regimens for diabetics depending on the stage of nephropathy, albumin, creatinine and GFR.So, if the creatinine increases 300 μmol / l, the dosage of the ATP inhibitor is halved, if it jumps higher, and completely abolished - before hemodialysis. In addition, modern medicine is constantly searching for new drugs and therapeutic schemes that allow simultaneous treatment of diabetes and diabetic nephropathy with minimal complications.
On the video about the causes, symptoms and treatment of diabetic nephropathy: