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What is chronic renal failure?

1.what is the kidney?

Kidney is a very important organ of the human body, the shape of "cashew nuts", located at the junction of the back of the lumbar spine and the twelfth rib of the human body. The vast majority of people have left and right kidneys, and very few people develop solitary kidney (unilateral kidney defect), horseshoe kidney (two kidneys are connected with each other, shape like horseshoe), ectopic kidney (such as growing in the pelvic and other parts) due to abnormal development. The size of normal adult male is 11 cm x 6 cm x 3 cm, the left kidney is slightly larger than the right kidney, while the female kidney is slightly smaller than that of the same age male. Although it shares the same word with "kidney", one of the five organs in Chinese medicine theory, it is a completely different concept.

2. the role of the kidney?

The basic function of the kidney is filtering the blood, the body produces or metabolites of absorption and some waste, toxins and other harmful substances and excess minerals and water, the formation of urine excreted by the body,is an important "wastewater treatment plant" for human body. At the same time, the useful substances filtered out are sucked into the blood to prevent the loss of beneficial substances, so as to maintain the stability of the environment in the body. In addition, the kidney has endocrine function, can produce hormones, affect a variety of physiological processes throughout the body, and thus closely related to the general condition. For example, erythropoietin can promote erythropoiesis; renin system closely related to blood pressure; regulation of calcium and phosphorus metabolism and bone activity; vitamin D3 and so on. It is also a part of endocrine hormone degradation sites and places of action. These functions of the kidney ensure the stability of the environment in the body and make the metabolism go to normal.

3. What is chronic renal failure?

Chronic renal failure is not an independent disease, but a clinical status that on the basis of various chronic kidney diseases that renal function damage occurs until complete failure. When chronic renal failure reaches late, the kidney function is completely lost, and it has a well-known name - "uremia". However, although the public is familiar with the term "chronic renal failure", the concept has been abandoned in medicine and will gradually be replaced by "chronic kidney disease".

4. What is the relationship between chronic kidney disease and chronic renal failure?

Chronic renal failure represents the whole process of impairment of renal function to complete loss, and in order to better evaluate the various stages of chronic renal failure in order to provide more targeted treatment interventions, the concept of chronic kidney disease (CKD) has been proposed and has been gradually replaced by the concept of chronic renal failure.

When the various causes of renal morphological structure or functional abnormalities, especially the filtration function decreased, affecting its normal work, mainly for the progressive increase of serum creatinine; and this anomaly persist, more than three Month can not be restored, we define it as "chronic kidney disease". This exception can be embodied in specific blood, urine abnormalities, or renal imaging abnormalities. According to the degree of impaired renal function, chronic kidney disease is artificially pided into 1-5 periods.

At the same time must be stressed that this definition is artificial pision, must be determined by the doctor according to clinical conditions, can not be used by their own rigid.

5. What are the symptoms of chronic kidney disease?

Chronic kidney disease can be caused by kidney disease or other systemic diseases of the body. In addition to the symptoms associated with primary diseases associated with chronic kidney disease, the impairment of renal function itself can also affect the whole body system, resulting in a wide range of non-specific manifestations. Common as urine output decreased, and nocturnal urine increased urine; Systemic edema; nausea and vomiting, loss of appetite; pruritus; cough, chest tightness, shortness of breath, can not lie, even death; In the early stages of chronic kidney disease, often more hidden, most of the time without any impact on life, but not be aware of and pay attention to the majority of patients.

6. How many people suffering from chronic kidney disease?

The number of people with chronic kidney disease in China has no exact figures. The latest epidemiological study shows that about 10.8% of adults with chronic kidney disease in China over 18 years of age and about one in 9 adults has chronic kidney disease. And only 12.5% of them know that they are in such a bad state.


7. Who needs to pay special attention to kidney function?

(1) the elderly;

(2) long-term diabetes and hypertensive patients;

(3) various autoimmune diseases, such as systemic lupus erythematosus;

(4) inpiduals with a family history of kidney disease, such as polycystic kidney;

(5) have acute kidney disease (such as acute nephritis, acute tubular necrosis, acute interstitial nephritis) of the inpidual, need to focus on kidney recovery;

(6) long-term gout, hyperuricemia patients;

(7) some infections such as pharynx, intestinal, urinary tract or hepatitis B virus infection and long-term use of certain nephrotoxic, Western medicine; cancer patients, such as multiple myeloma.

Because the kidney has a strong compensatory capacity, most patients have no symptoms at the early stage of functional impairment, and more need to rely on regular examination of kidney related indicators to early detection.

8. What can be done to evaluate kidney function?

Routine examination of the kidneys are:

(1) urine routine, urine protein, urine red blood cell, tube type and other abnormalities can be found;

(2) 24 hours urine protein, collecting 24 hours urine, can be more accurate detection of urine protein content;

(3) renal function tests, such as serum creatinine, blood urea nitrogen, serum cystatin C, creatinine clearance, renal perfusion ECT;

(4) imaging studies, such as kidney B ultrasound, CT, can be found in kidney changes: size, polycystic kidney;

(5) can even through the puncture method, to take part of the kidneys to conduct pathological examination, clear the reasons for kidney damage.

9. Does renal function mean serum creatinine?

Serum creatinine is simple to detect and is commonly used clinically to assess the detection of renal function. Many people are exposed to regular physical examination. Many doctors will be based on whether the normal range of serum creatinine to determine the kidney function is good or bad.

But serum creatinine is not equivalent to kidney function.Renal function refers to the ability of the blood to filter and wash in the kidneys and cannot detect itself. And creatinine is the product of muscle metabolism, in a certain period of time, the body's creatinine production is relatively constant, while most of the creatinine through the kidneys excreted. So if the renal filtration function is impaired, creatinine will accumulate in the body. So serum creatinine to a certain extent can be used as an indirect evaluation of renal function indicators, it is only an indicator. Serum creatinine has many defects, only serum creatinine can not timely and accurate response to renal function, and early chronic kidney disease, serum creatinine levels may not have increased. At the same time, some drugs, by affecting muscle metabolism, to reduce the serum creatinine value, and can not represent the improvement of renal function. It is thought that serum Cystatin C is more representative of renal function, especially for the diagnosis of early chronic kidney disease.

10. The goal of treatment of chronic kidney disease?

A variety of causes of kidney disease, if the damaged part has been hardened to the current medical level can not be reversed, which means that the loss of functional part of the kidney can not be restored, can only rely on the remaining part of the kidney compensatory loss. The goal of treatment of chronic kidney disease is not to restore complete health, but to protect the remaining kidney function, delaying the time of renal function into the failure period; thus extending the life expectancy of patients to ensure the quality of life of patients.

11. How to treat chronic kidney disease?

Treatment of chronic kidney disease includes the following:

(1) etiology of treatment: find the culprit leading to chronic kidney disease,treat the primary disease, to reduce the damage to the kidney.

(2) risk factors: If the cause can not be eliminated, then the need to reduce other factors that may affect kidney function, to avoid worse. At present, the more widely recognized risk factors are: long-term hypertension; diabetes; persistent proteinuria; persistent hyperuricemia; the use of nephrotoxic drugs; the use of contrast agents and so on.

(3) prevention and treatment of complications: the gradual loss of renal function in the process, the body of the various systems will be affected by the abnormal, that is, complications. Need to intervene against these exceptions to help the body remain stable.

(4) When renal function has been completely exhausted and insufficient to maintain survival, it is necessary to seek alternatives to renal function, that is, kidney replacement therapy.


12. What diet should be paid attention to in patients with chronic kidney disease?

With the progress of chronic kidney disease, diet is not immutable.

(1) before suffering from chronic kidney disease, as a first-class prevention, diet need to pay attention to high blood pressure, diabetes and other risk factors, such as low-salt diet, diabetes diet.

(2) in the process of progressive progress of chronic kidney disease, as a secondary prevention, the purpose of diet is to delay the progress of kidney disease, delay into chronic renal failure, and need to focus on the prevention and treatment of complications. According to the clinical situation need to consider low-salt diet, diabetes diet, low purine diet, low-phosphorus diet, and the need to control the type and content of protein in the diet. The principle is: enough is enough, more is the burden.

(3) In patients with chronic renal failure, especially in patients receiving dialysis, malnutrition has become an important factor in threatening survival, and adequate nutrition needs to be paid more attention.

13. Why are chronic kidney disease patients with low-phosphorus diet?

Phosphorus is an important mineral element in our body. Organic phosphorus is an important component of proteins, cell membranes and energy substances in the body. Inorganic phosphorus is combined with calcium to build our strong bones. Impaired kidney function means that a large amount of waste can not be excreted from the body and will accumulate in the body, and phosphorus is one of them. These accumulation of phosphorus have a huge impact on the patient's heart, blood vessels, bones . Therefore, the management of phosphorus is a very important task for patients with chronic renal failure.

14. What is a low-phosphorus diet?

Phosphorus is a component of protein, often rich in protein foods, such as pork, poultry and fish, phosphorus content is very high. But lack of protein intake can cause malnutrition, the same will also affect health, increase mortality, trade-offs.

If blood phosphorus exceeds the control target, our goal is to limit phosphorus intake (800-1000 mg / d).

(1) limit the amount of protein intake, to ensure adequate protein under the premise of reducing protein intake. In order to take into account the low phosphorus and adequate intake of protein, you can choose low phosphorus and protein ratio of food, such as egg protein.

(2) choose the appropriate type and source of protein. Because plant-derived phosphorus is not easily absorbed by the body.

(3) limit the intake of phosphorus-containing food additives and certain high-phosphorus foods. Phosphorus is one of the main ingredients of preservatives and additives in food products and is usually present in phosphate form, including certain beverages, processed meat products, instant food, fast food, instant food, cereals, cheeses and frozen baking Products and so on. Phosphorus in the additive is easily absorbed by the body and significantly increases the phosphorus load.

15. Why are chronic kidney disease patients with low protein diet?

Modern medical research found that patients with chronic kidney disease can reduce the rate of renal dysfunction by reducing protein intake as much as possible to meet the physiological needs.And try to intake of essential amino acids rich in protein, such as eggs, fish, lean meat and milk, the so-called "high-quality protein." Try to reduce plant proteins, such as peanuts and their products. There are no authoritative conclusions about how much protein can be ingested every day. About 0.6 g/kg per day can meet the basic needs of the human body. Again, we must pay great attention to the nutritional status, and can not go to the other extreme. The low protein diet essentially doesn't eat protein, but means avoiding excessive intake of protein.

16. Why are chronic kidney disease patients with low-salt diet?

The main ingredient of salt is sodium chloride, is an important way for human body to absorb sodium. In patients with chronic kidney disease, excessive intake of "sodium" is not conducive to control the disease. Especially for patients with edema, oliguria, or hypertension. How much salt can we eat? The World Health Organization (WHO) recommends that adults daily intake of salt (sodium chloride) should not exceed 5 g (about 2000 mg sodium).


17. Why are patients with chronic kidney disease have a low purine diet?

Patients with chronic kidney disease due to decreased renal excretion, uric acid excretion is also affected, often combined with hyperuricemia; and hyperuricemia in turn can also increase kidney damage. Uric acid is a metabolite of purines, so most patients with chronic kidney disease require a low purine diet. Purine is a component of purine nucleoprotein and is an indispensable substance for cells. Thus, not so elegantly, the more the number of cells, the higher the purine content will be. Comparison of the "famous" high purine diet include: seafood, animal offal, soy products, while the need to avoid alcohol intake.


18. What are the complications of chronic kidney disease?

Kidney function is gradually lost until the final failure, in the process, the body's various systems will be affected, resulting in a variety of complications,such as decreased resistance, infection, anemia, mineral metabolic disorders; renal bone malnutrition; osteoporosis ; Vascular calcification; uremia-related encephalopathy and neuropathy etc.. And long term renal function is impaired, leading to cardiac structural changes through a series of mechanisms, thus causing cardiovascular events is the leading cause of death in patients with chronic renal failure; many patients did not even enter the period of renal failure had been due to cardiovascular events and death.

19. What are the complications of chronic kidney disease?

(1) antihypertensive therapy: blood pressure is one of the major causes of glomerular sclerosis and residual nephron loss. Timely and reasonable antihypertensive therapy, can reduce proteinuria, delay the development of CRF, protect the heart, brain and other target organs, to improve the prognosis of patients. Commonly used antihypertensive drugs such as diuretics, beta blockers, angiotensin converting enzyme inhibitors (ACEI), angiotensin Ⅱ receptor antagonists (ARB), calcium channel blockers (CCB) and so on.

(2) renal osteopathy: renal osteopathy is a common complication of CRF, mainly fibrocystic osteitis (caused by secondary hyperparathyroidism), bone softening, bone regeneration, osteoporosis, etc. , active vitamin D can be used to treat renal osteodystrophy according to the level of serum parathyroid hormone (PTH).

(3) anemia: anemia is a common manifestation of CRF patients, non-dialysis CRF patients with severe anemia should be taken seriously. Clinical studies have shown that the use of recombinant human erythropoietin (rhEPO) to correct anemia, and iron and folic acid supplement, can delay the progress of renal insufficiency.

(4) metabolic acidosis: clinical usually given oral or intravenous infusion of sodium bicarbonate to correct acidosis.

(5) hyperkalemia: intravenous injection of calcium gluconate and / or glucose - insulin intravenous infusion, severe hyperkalemia should be given timely dialysis treatment.

(6) hyperphosphatemia: hyperphosphatemia, in addition to limiting phosphorus intake, the oral phosphorus binding agent (calcium carbonate, calcium citrate, calcium acetate, etc.)

20. What are the ways of renal replacement therapy?

There are two types of mature kidney replacement methods, namely, kidney transplantation and dialysis treatment, and dialysis treatment is pided into hemodialysis and peritoneal dialysis. Hemodialysis is the use of man-made machines, that is, hemodialysis machine, the blood out of their own body of the machine, after washing back to their own body. Peritoneal dialysis is to use their own intraperitoneal peritoneum to achieve the purpose of removing toxins and water. Kidney transplant, as the name suggests, is the other people's kidneys transplanted to their own body, for their own body work, pided into living donor kidney (relatives or others donated) and the body for the kidney (brain death or brain death sources).

With the possibility of long-term renal replacement, chronic renal failure is no longer a "terminal disease", and into a "chronic disease."

21. When should I start kidney replacement therapy?

Kidney replacement therapy can help the body's environment stability, improve patient symptoms, improve patient quality of life, and even allow patients to return to society with confidence. But early start dialysis will not only lead to waste of medical resources, increase the risk of iatrogenic injury, while increasing the family and social financial burden; and late dialysis not only reduce the quality of life, but also affect the long-term life expectancy.

There is no clear evidence to tell patients which criteria need to be replaced by the kidney; need to consider the reduction of glomerular filtration rate and nutritional status of patients, chronic renal failure clinical symptoms and signs are the factors that need attention. And severe hypercholesterolemia, water or acute pulmonary edema, is an indication of emergency dialysis. Many patients are delayed until this time began to dialysis, bringing a series of complications, resulting in greater burden.


22. What are the preparations for patients with chronic kidney disease before dialysis and their families?

If the patient is expected to inevitably enter the uremic period, need to do the appropriate preparation in advance. In the body, the need to focus on the complications of chronic kidney disease control, such as heart function, anemia, kidney bone disease. In the psychological need for a correct understanding of the disease, to avoid the wrong perception of unnecessary panic and anxiety. Understanding of chronic kidney disease, although to bring a lot of troubles to life, but not can not cure terminally ill. You can communicate with doctors and patients to understand the future need to face the life. We should understand various renal replacement methods, and choose the most suitable way according to their own conditions. Health care policy, economic ability, family support, psychosocial factors, local medical conditions and medical factors need to be considered. Each method has its own advantages and disadvantages, and can be complementary to each other.

23. What is hemodialysis of chronic kidney disease?

Hemodialysis is the use of "artificial kidney" - dialysis machine, to complete the blood purification. It and peritoneal dialysis are just a part of the function of the kidney, that is, filtering function. The patient's blood through a blood vessel into the dialysis machine, in the dialyzer material exchange between through dialysis membrane and dialysis fluid, then the purified blood transfusion to the body of toxins, in order to to discharge toxins and correct the disorder of water, electrolyte and acid-base balance.

24. What are the advantages and disadvantages of hemodialysis?


Compared to peritoneal dialysis, hemodialysis more efficient, can be removed in a short time the body of excess water and toxins, especially for pulmonary edema, hyperkalemia and drug poisoning rapid rescue.


(1) patients need to be treated at work time to dialysis centers, often affecting normal employment and out of society;

(2) hemodialysis will be in the blood circulation in vitro, and the need for rapid dehydration and elimination of toxins, requiring patients with a very good heart function;

(3) the need to establish vascular access, there are vascular pathways associated with the risk, such as bleeding, infection, fistula stenosis, thrombosis and so on;

(4) for the first time into hemodialysis or serum levels of toxins in patients with high levels of treatment may occur after cerebral edema and dialysis imbalance syndrome;

(5) low blood pressure is more common, may be related to the rapid clearance of water; significantly affect the long-term life and life of patients.







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