Diabetic nephropathy - Causes, symptoms and treatment. MF.
Diabetic nephropathy is a renal vascular disease that occurs with diabetes mellitus, which is accompanied by their replacement with dense connective tissue( sclerosis) and the formation of renal failure.
Causes of diabetic nephropathy
Diabetes mellitus is a group of diseases caused by a defect in the formation or action of insulin, and accompanied by a persistent increase in blood glucose levels. In this case, type 1 diabetes mellitus( insulin-dependent) and type II diabetes mellitus( insulin-independent) are isolated. With prolonged exposure to high glucose levels, vessels and nervous tissue develop structural changes in organs that lead to complications of diabetes. Diabetic nephropathy is one such complication.
In type 1 diabetes mellitus, mortality from renal insufficiency ranks first, in type II diabetes, it ranks second after cardiovascular disease.
Increased blood glucose is the main provoking factor in the development of nephropathy. Glucose has not only a toxic effect on the cells of the kidneys, but also activates some mechanisms that cause damage to the walls of blood vessels, increase its permeability.
Kidney damage in diabetes.
In addition, great importance for the formation of diabetic nephropathy has an increase in pressure in the vessels of the kidneys. This is a consequence of inadequate regulation in diabetic neuropathy( damage to the nervous system in diabetes mellitus).In the final, the damaged vessels are replaced with scar tissue, the kidney function is severely impaired.
Symptoms of diabetic nephropathy
Several stages are distinguished in the development of diabetic nephropathy:
I stage - kidney hyperfunction. Appears in the onset of diabetes. The cells of the kidney vessels increase somewhat in size, the excretion and filtration of urine increases. The protein in the urine is not determined. There are no external manifestations.
II stage - the initial structural changes. Occurs an average of 2 years after diagnosing diabetes. Characterized by the development of thickening of the walls of the vessels of the kidneys. The protein in the urine is also not determined, that is, the excretory function of the kidneys does not suffer. Symptoms of the disease are absent.
Over time, usually after five years, there is the III stage of the disease - the onset diabetic nephropathy .As a rule, with a routine examination or during the diagnosis of other diseases in the urine, a small amount of protein is determined( from 30 to 300 mg / day).This condition is called microalbuminuria. The appearance of protein in the urine indicates significant damage to the kidney vessels.
Mechanism of the appearance of protein in the urine.
At this stage, there are changes in glomerular filtration rate. This indicator characterizes the filtration of water and low molecular weight harmful substances through the renal filter. At the onset of diabetic nephropathy, the rate of glomerular filtration may be normal or slightly elevated due to increased pressure in the kidney vessels. There are no external manifestations of the disease.
These three stages are called preclinical, as there are no complaints, and renal damage is determined only by special laboratory methods or by microscopy of the kidney tissue during biopsy( sampling part of the organ for diagnostic purposes).But identifying the disease at these stages is very important, because only at this time the disease is reversible.
IV stage - marked diabetic nephropathy occurs in 10-15 years from the onset of diabetes mellitus and is characterized by vivid clinical manifestations. A large amount of protein is excreted in the urine. This condition is called proteinuria. In the blood, the protein concentration sharply decreases, massive swelling develops. With a small proteinuria, swelling occurs in the lower extremities and on the face, then with the progression of the disease, edema becomes common, the fluid accumulates in the body cavities( abdominal, thoracic cavities, pericardial cavity).In the presence of severe renal damage, diuretics for the treatment of edema become ineffective. In this case, resort to surgical removal of fluid( puncture).To maintain the optimal level of protein, the body begins to break down its own proteins. Patients strongly lose weight. Also, patients complain of weakness, drowsiness, nausea, decreased appetite, thirst. At this stage, almost all patients notice an increase in blood pressure, sometimes to high figures, which is accompanied by headache, shortness of breath, pain in the heart.
V stage - uremic - final of diabetic nephropathy , terminal stage of renal failure. The kidney vessels are completely sclerosed. The kidney does not fulfill its excretory function. The glomerular filtration rate is less than 10 ml / min. Symptoms of the previous stage are preserved and take a life-threatening character. The only way out is substitution renal therapy( peritoneal dialysis, hemodialysis) and transplantation( persadka) of the kidney or kidney-pancreas complex.
Diagnosis of diabetic nephropathy
Routine tests do not allow diagnosis of preclinical stages of the disease. Therefore, all patients with diabetes showed the definition of albumin urine by special methods. The detection of microalbuminuria( from 30 to 300 mg / day) indicates the presence of diabetic nephropathy. The determination of the glomerular filtration rate has a similar value. An increase in the glomerular filtration rate indicates an increase in pressure in the vessels of the kidneys, which indirectly indicates the presence of diabetic nephropathy.
The clinical stage of the disease is characterized by the appearance of a significant amount of protein in the urine, arterial hypertension, damage to the vessels of the eye with the development of visual impairment and a progressive steady decrease in the glomerular filtration rate, the glomerular filtration rate on average drops by 1ml / min every month.
V stage of the disease is diagnosed with a decrease in the glomerular filtration rate of less than 10 ml / min.
Treatment of diabetic nephropathy
All measures for the treatment of diabetic nephropathy are divided into 3 stages.
1. Prevention of renal vascular disease in diabetes mellitus. This is possible with the maintenance of optimal blood glucose level due to the proper use of hypoglycemic drugs.
2. In the presence of microalbuminuria, the priority is also the maintenance of normal blood sugar levels, as well as the treatment of arterial hypertension, which often occurs already at this stage of the disease. The optimal drugs for the treatment of high blood pressure are considered to be angiotensin-converting enzyme( ACE) inhibitors, for example, enalapril, in small doses. In addition, a special diet with a maximum protein content of not more than 1 g per 1 kg of body weight is of great importance.
3. With the appearance of proteinuria, the main goal of the treatment is to prevent the rapid reduction of kidney function and the development of terminal renal failure. The diet introduces more stringent restrictions on the protein content of food: 0.7-0.8 g per 1 kg of body weight. With a low protein content in food, decay of the body's own proteins may occur. Therefore, with the substitutional goal, it is possible to designate ketone analogs of amino acids, for example, ketosteril. It remains relevant to maintain optimal blood glucose levels and correct high blood pressure. To ACE inhibitors, calcium channel blockers( amlodipine) or beta-adrenoblockers( bisoprolol) are added. When edema is prescribed diuretic drugs( furosemide, indapamide) and control the amount of fluid drunk about 1 liter per day.
4. When the glomerular filtration rate is lower than 10 ml / min, renal replacement therapy or transplantation( transplantation) of organs is indicated. Currently, renal replacement therapy is represented by methods such as hemodialysis and peritoneal dialysis. But the best way to treat the terminal stage of diabetic nephropathy is to transplant the kidney-pancreas complex. By the end of 2000, more than 1,000 successful transplants were performed in the United States. In our country, transplantation of a complex of organs is at the development stage.
Physician therapist, nephrologist Sirotkina EV