Renal failure is called a gradual decrease in renal function, which is caused by the death of nephrons, provoked by chronic diseases. The gradual extinction of functions can lead, as a rule, to disruption of the functioning of the whole organism, as well as to the appearance of various complications from some systems and organs.
There are several forms of this pathology: latent, intermittent, compensated, and terminal. Diagnostic measures to determine this disease involve special clinical and biochemical analyzes, samples of Rehberg and Zimnitsky, ultrasound, ultrasound of the vessels of the kidneys, etc. The treatment of this pathology is based on the fight against the underlying disease, as well as on symptomatic treatment and extracorporeal hemocorrection.
Chronic form
Chronic renal failure is considered an irreversible violation of their excretory and filtration functions, up to the complete death of renal tissue. The pathological process has a progressive course. With the development of the disease, there is an increase in its symptoms, which are weakness, loss of appetite, vomiting, swelling, nausea, dry skin, etc. Diuresis sharply decreases, in some cases - until its complete cessation. In the later stages, heart failure, pulmonary edema, a tendency to bleeding, encephalopathy, and uremic coma can develop. In this case, the patient is shown hemodialysis and kidney removal.
Causes of Renal Failure
What are the reasons? Depending on them, acute renal failure is divided into:
- Prerenal. It arose due to impaired renal blood flow.
- Renal. The reason is the pathology of the kidney tissue.
- Postrenal. The outflow of urine is impaired due to an obstruction in the urethra.
The chronic form occurs due to:
- Congenital and hereditary kidney disease.
- Kidney damage in chronic pathologies. These include gout, urolithiasis, diabetes, metabolic syndrome, scleroderma, cirrhosis, obesity, systemic lupus erythematosus, etc.
- A variety of pathologies of the urinary system, when the urinary tract gradually overlaps: tumors, urolithiasis.
- Kidney disease: chronic glomerulonephritis, chronic pyelonephritis.
- Improper use, overdose of drugs.
- Chronic poisoning with toxic substances.
Pathogenesis
Renal failure can result from glomerulonephritis, hereditary nephritis, kidney inflammation in systemic diseases of chronic pyelonephritis, amyloidosis or polycystosis, glomerulosclerosis in diabetes mellitus, nephroangiosclerosis and a number of other diseases that affect both or one kidney at once.
The main characteristic of this pathological process is the progression of nephron death. At an early stage of the disease, renal functions become weakened, after which a significant decrease in their functions is observed. Histological studies confirm the death of the kidney parenchyma, which is gradually replaced by connective tissue cells.
What precedes this?
The development of a patient's renal failure, as a rule, is preceded by the occurrence of chronic diseases in the period from 3 to 10 years, and sometimes more. The development of kidney pathology before the onset of their chronic insufficiency is conditionally divided into certain stages, and the choice of tactics for treating this disease directly depends on them.
Disease classification
The following stages of this pathological process are distinguished:
- Latent stage. At this period, the disease proceeds without particularly pronounced symptoms. As a rule, it is detected only after the results of an in-depth clinical study. Glomerular filtration of the kidneys in this reduced to 60-70 ml / min. Some proteinuria is also noted.
- Compensated stage of renal failure. At this stage, the patient is concerned about fatigue and a feeling of dry mouth. The volume of urine increases with a decrease in its density. The decrease in glomerular filtration is up to 50-40 ml / min. Creatinine and urea levels also increase.
- Intermittent stage of chronic renal failure. Pronounced clinical symptoms of the disease are observed. Specific complications arise that are caused by an increase in kidney failure. The condition of the patient may change in waves. Glomerular filtration during this period decreases to 25-15 ml / min., Acidosis and persistence of high creatinine levels are observed.
- Terminal renal failure. It, in turn, is divided into four stages:
- I. Diuresis is more than 1 liter per day. Filtration - 15-10 ml / min.
- II-a. Urine volume is reduced to 500 ml, there is hypernatremia and hypercalcemia and an increase in symptoms of fluid retention and decompensated acidosis.
- II-b. Signs become even more pronounced, heart failure develops, congestion in the lungs and liver is noted.
- III. Strong uremic intoxication, hyponatremia, hypermagnesemia, liver dystrophy, hyperkalemia, hypochloremia, polyserositis develop.
Body damage
Changes in the blood of the patient: anemia, which is due to inhibition of hematopoiesis and a reduction in the life span of red blood cells. Clotting disorders are also noted: thrombocytopenia, lengthening of the bleeding period, and a decrease in the amount of prothrombin.
Complications developing in the lungs and heart: arterial hypertension (in almost half of patients), heart failure, myocarditis, pericarditis, uremic pneumonitis (in the later stages).
Changes in the nervous system: in the early stages - sleep disturbance and distraction, in the later stages - inhibition of reactions, confusion, delirium, hallucinations, peripheral polyneuropathy.
Digestive disorders: in the early stages - decreased appetite, dry mouth, belching, nausea, stomatitis. Due to mucosal irritation, enterocolitis and atrophic gastritis may develop. Ulcerous lesions of the stomach and intestines are formed, which often become sources of bleeding.
Pathologies of the musculoskeletal system: different forms of osteodystrophies are characteristic of renal failure in men and women - osteosclerosis, osteoporosis, osteitis of a fibrous nature, etc. The clinical manifestations of osteodystrophy are spontaneous fractures, compression of the vertebrae, skeletal deformity, arthritis, muscle and bone pain.
On the part of the immune system, the development of lymphocytopenia is often observed. A decrease in immune defense causes an increase in the frequency of development of purulent-septic formations.
Consider how renal failure manifests itself in women and men.
Symptoms of pathology
In the period that precedes the development of this pathological process, renal functions are preserved in full. Glomerular filtration levels are not disturbed. At subsequent stages, glomerular filtration begins to decline, and the kidneys lose the ability to concentrate urine, which affects the kidney processes. Homeostasis at these stages is not yet broken. However, subsequently, the number of workable nephrons decreases sharply, and the patient begins to appear the first signs of renal failure.
Symptoms depending on the stage
Patients with a latent stage of this disease of complaints, as a rule, do not show. In some cases, they may indicate mild weakness and a breakdown. Increased fatigue may disturb patients with compensated renal failure. With the development of an intermittent stage, more pronounced symptoms of the disease are observed. Weakness intensifies, patients may complain of constant thirst and loss of appetite. Their skin is pale, dry. At the terminal stage, patients, as a rule, lose weight, their skin acquires a gray-yellow hue, becomes flabby. Also characteristic for this stage of the pathology are: itchy skin, decreased muscle tone, hand tremors, muscle twitches, and thirst and dry mouth are intensified. The occurrence of apathy, drowsiness, distraction can also be noted.
With the intensification of intoxication processes, a characteristic smell from the mouth, nausea, begins to appear. Periods of apathy, as a rule, are replaced by excitement, inadequacy. Also in this case, manifestations of dystrophy, hoarseness, hypothermia, aphthous stomatitis are characteristic. The patient’s abdomen is swollen, frequent vomiting and loose stools of a dark color are noted. Patients may also complain of excruciating itching of the skin and muscle twitching. The degree of anemia is growing, hemorrhagic syndromes are developing, as well as renal osteodystrophy. Characteristic manifestations of renal failure in women of this stage are: ascites, myocarditis, encephalopathy, pericarditis, uremic coma, pulmonary edema.
Pathology diagnostics
If you suspect the development of this pathology, it is necessary to conduct certain laboratory tests:
- biochemical blood test;
- Reberg tests;
- determination of creatinine and urea levels;
- Zimnitsky test.
Tests for kidney failure are prescribed by a doctor.
In addition, an ultrasound scan is required to determine the thickness of the parenchyma and the total size of the kidneys. Doppler ultrasonography of blood vessels will allow to identify intraorgan and main blood flow. In addition, a study such as radiopaque urography is also used, but this should be used with caution, since many contrast agents have high toxicity to kidney cells.
Treatment
What is timely therapy aimed at slowing the development of renal failure and reducing the clinical symptoms of the disease?
The main aspect here is the treatment of the underlying disease, which provoked the development of this pathology. The patient needs special dietary nutrition. If necessary, he may be prescribed antibacterial drugs and antihypertensive drugs. Sanatorium and resort treatment is also shown. In addition, careful monitoring of the level of glomerular filtration, renal blood flow, concentration function of the kidneys, level of urea and creatinine is required.
With changes in homeostasis, it is possible to correct the acid-base composition, water and salt balance of the blood. It should be noted that symptomatic therapy, as a rule, consists in the treatment of anemic, hemorrhagic and hypertensive syndromes, as well as in the maintenance of cardiac functions.
Diet for kidney failure
Patients who have this pathology are prescribed a low-protein diet with a large amount of calories, which includes a large number of essential amino acids. It is necessary to minimize the amount of salt consumed, and with the development of hypertension - completely eliminate salt intake.
The protein content in the patient's diet should depend on the degree of damage to the renal functions: with glomerular filtration below 60 ml / min, the amount of protein should be reduced to 40 grams per day, and if this indicator is below 30 ml / min - up to 25 grams per day.
Symptomatic treatment
When renal osteodystrophy occurs, patients are prescribed vitamin D, preparations with a high calcium content, but one should remember about organ calcification, a very dangerous morphological process caused by high doses of vitamin D. Sorbitol and aluminum hydroxide are prescribed to reduce hyperphosphatemia. And a prerequisite here is control during treatment of the level of calcium in the blood and phosphorus.
With anemia
When anemia is prescribed, as a rule, drugs with a high content of iron, folic acid, androgens. With a decrease in hematocrit, transfusions of red blood cells are carried out. The use of chemotherapeutic drugs and antibacterial drugs is determined depending on how they are excreted. The dose of sulfanilamide, ampicillin, cephaloridine, penicillin and methicillin decreases in this case several times, and when taking polymyxin, monomycin, neomycin and streptomycin, certain complications may develop, for example, auditory nerve neuritis, etc. Nitrofurans are contraindicated in patients suffering from renal failure.
The use of glycosides in the treatment of such consequences of this pathology as heart failure should occur strictly under the supervision of a specialist and laboratory parameters. The dosage of such medications decreases with the development of hypokalemia. Patients with intermittent stage of renal failure, especially during periods of exacerbation, are prescribed hemodialysis.