With the aging process of the population, the number of elderly patients with chronic kidney disease has increased significantly, and effective prevention and treatment of chronic kidney disease in the elderly is a common public health need in many countries. Diabetic nephropathy is a common disease among renal diseases in the elderly and has attracted increasing attention. The prevention and treatment of diabetic nephropathy should emphasize early diagnosis and early treatment.
How does diabetic nephropathy occur?
The typical diabetic nephropathy is mainly glomerulosclerosis. This comorbidity is generally considered to be part of systemic microangiopathy and is mainly due to thickening of the capillary basement membrane. In diabetes mellitus there are disorders of sugar, protein and fat metabolism. Glucose is actively metabolized via the pentose phosphate pathway, which promotes the synthesis of basement membrane glycosylated proteins, and non-enzymatic glycosylated protein synthesis increases in hyperglycemia, which precipitates in the basement membrane of glomerular capillaries or binds directly to the basement membrane, thickening it. In addition, this microangiopathy is associated with genetic factors and elevated growth hormone in the presence of diabetes.
What are the high risk factors for diabetic nephropathy?
The main ones are hyperglycemia, hypertension and high protein intake. In a chronic hyperglycemic state, vascular permeability increases and proteins tend to leak out and deposit. Although hypertension is not a factor in the development of diabetic nephropathy, hypertension can aggravate the excretion of urinary albumin and accelerate the progression of diabetic nephropathy and deterioration of renal function. High protein diet can accelerate kidney damage in patients with renal insufficiency. In addition, recent years have confirmed that smoking is also a risk factor for diabetic nephropathy, and some statistics show that 19% of diabetic smokers have proteinuria, while only 8% of nonsmokers have proteinuria.
What are the signs that indicate possible diabetic nephropathy?
1. Increased nocturia.
When diabetic patients have increased nocturnal urine, it means that the kidneys may have been involved. Normal people urinate more during the day than at night; when the renal tubules are involved, the ability to concentrate decreases and the amount of urine increases at night.
2. Swelling.
It is due to the long-term loss of protein by the kidneys and the decrease of plasma albumin level. Therefore, swelling is no longer a manifestation of early diabetic nephropathy, but indicates that diabetic nephropathy has existed for quite some time.
3. Hypertension.
Hypertension can cause kidney damage, and kidney damage can also cause hypertension. Diabetic patients with hypertension are often accompanied by kidney damage.
4.Urine protein.
The presence of intermittent or persistent urine protein indicates stage III diabetic nephropathy.
How to detect diabetic nephropathy early?
The earliest manifestation of diabetic nephropathy is that the filtration rate of the glomerulus can increase, the volume of both kidneys increases, and there are no clinical symptoms. It can only be detected by special laboratory tests (nuclear medicine and ultrasound). The detection of protein in routine urine tests indicates that the nephropathy is not early. Currently, the rate of urinary albumin excretion can be measured by radioimmunoassay, and the normal value is below 20 micrograms per minute. If it rises to 20~200 micrograms/minute, it means that it is the early stage of diabetic nephropathy, that is, treatment should be started to protect the kidney and slow down the progress of nephropathy. Generally, people with a history of diabetes for more than 10 years are accompanied by different degrees of kidney damage.
What are the conditions that are not diabetic nephropathy?
The following conditions are not diabetic nephropathy (glomerulosclerosis) although there is proteinuria.
1.Patients with poorly controlled diabetes mellitus have positive urine protein, but after good control of diabetes mellitus, urine protein can turn negative.
2, Glomerulosclerosis caused by hypertension can also produce proteinuria, but with a longer history of hypertension.
3, Urinary tract infection can produce pseudoproteinuria, and the kidney should be evaluated after the infection is eliminated.
4, Some people have combined glomerulonephritis, and the diagnosis of such patients is quite difficult. The differential diagnosis depends on kidney biopsy.
How many stages of diabetic nephropathy can be divided?
Diabetic nephropathy is generally divided into 5 stages from mild to severe.
Stage I: Early hyperplasia with hyperfiltration. This stage is characterized by kidney hyperplasia, enlargement and hyperfiltration. This stage can be partially reversed with insulin treatment.
Stage II: The kidney has lesions, but there are no clinical signs. Urinary albumin excretion is normal, and physical activity increases urinary albumin, which recovers after rest. Renal puncture biopsy showed thickened basement membrane. Glomerular filtration rate is still increased.
Stage III: Occult diabetic nephropathy, also known as early diabetic nephropathy stage. The main manifestations are abnormally elevated urinary albumin excretion, increased blood pressure in about 1/5 patients, and still higher than normal or normal glomerular filtration rate. To develop this stage, there must be 10-15 years of history of diabetes mellitus.
Stage IV: Symptomatic diabetic nephropathy, i.e., the clinical diabetic nephropathy stage. This stage is characterized by proteinuria (persistent proteinuria and detectable by conventional methods), decreased glomerular filtration rate, and persistent hypertension and edema.
Stage V: End-stage renal failure. Azotemia usually begins after 20-25 years of diabetes mellitus. Later, the disease progresses, and in addition to significant hypertension and edema, metabolites such as blood urea nitrogen and creatinine are significantly retained, finally entering the uremic phase with hypoproteinemia. Patients in this stage sometimes need dialysis treatment.
When to start the treatment of diabetic nephropathy?
Treatment of patients with diabetic nephropathy depends on what stage the nephropathy is in. For patients without nephropathy (stage I and II), good blood glucose control is the key to preventing diabetic nephropathy. Patients with early stage nephropathy (stage III) should be treated aggressively and reasonably, including good control of blood glucose and blood pressure, nutritional adjustments and the use of angiotensin-converting enzyme (ACE) inhibitors, which can help slow the progression of nephropathy. For patients with more advanced kidney disease (stage IV), the goal of treatment is to slow the progression of kidney disease through good blood pressure control and dietary modification and avoiding excessive attention to blood glucose control. Excessive control of blood glucose may lead to complications, such as hypoglycemia.
The focus of the management of diabetic nephropathy is on early detection. People with diabetes-prone factors, such as family history of diabetes, multiple pregnancies, obesity and hypertension, should be screened for diabetes with a view to preventing diabetic nephropathy. Treatment of stage I, II and III diabetic nephropathy can lead to some degree of reversal; stage IV and V disease is progressive and irreversible. Once persistent proteinuria occurs, the disease will eventually develop into end-stage diabetic nephropathy.
How to prevent and treat diabetic nephropathy?
Diabetic nephropathy is one of the most serious microvascular complications of diabetes. Renal failure caused by diabetic nephropathy is 17 times higher than that of non-diabetic patients, and is one of the main causes of death in diabetic patients. Its clinical symptoms mostly manifest 5-10 years after the onset of the disease. Once diabetic nephropathy is diagnosed, it is irreversible, and even if the blood sugar is in the normal range, it cannot slow down the progress of renal insufficiency, therefore, prevention is extremely important. Prevention and treatment measures are mainly the following.
I. Control diet.
1, limit protein intake. For those who do not have elevated urea nitrogen, the daily intake of protein is 0.8 grams per kilogram of body weight. For those with elevated urea nitrogen, protein intake is 0.6 grams per kilogram of body weight per day. It is better to have animal protein, such as lean pork, beef, fish and eggs.
2, salt intake less than 5-6 grams / day, with renal insufficiency to 2 grams / day.
3.Do not eat pickled products.
4.Eating oil is better than vegetable oil.
Second, strict control of blood sugar.
1.Eugenol should not be used because of its powerful effect.
2, people with renal hypoplasia should not use biguanide hypoglycemic drugs, such as metformin, hypoglycemic, etc., to avoid lactic acidosis.
3.For people with kidney disease, it is better to use Gliquidone (Glucophage) because 95% of it is excreted by bile.
4. Glucophage is a kind of α-glucosidase inhibitor, which delays the absorption of glucose in the intestine and can reduce postprandial hyperglycemia. Because its absorption in the intestine is only 1%-2%, it has little effect on renal function.
5. If renal function damage is obvious and oral hypoglycemic drugs are not suitable, then insulin treatment should be switched to insulin early.
Third, the application of insulin.
It has been reported that in the early stage of diabetes, if treated intensively with insulin, diabetic nephropathy can be completely recovered in the early stage. For those whose blood sugar cannot be well controlled by diet control and (or) oral hypoglycemic drugs, they should be treated with insulin as early as possible. However, for patients with end-stage renal disease, it should be noted that hypoglycemia can easily occur due to inadequate feeding and decreasing insulin inactivation. Because the renal glucose threshold is elevated, even though the blood sugar is elevated, the urine sugar is often negative, so the blood sugar should be checked frequently at this time in order to adjust the insulin dose. There is no need to strictly control blood sugar in this period, because most of them have cardiovascular and cerebrovascular complications, and hypoglycemia will contribute to their occurrence.
IV. Strict control of blood pressure.
Usually blood pressure is best controlled below 130/80mmHg. Antihypertensive drugs can be chosen from angiotensin-converting enzyme inhibitors, such as captopril, enalapril, lortin, etc., or calcium antagonists, such as cardiac painkillers, etc.
V. Avoid factors of renal damage.
Minimize the use of various contrast agents. Patients should be supplemented as early as possible when they are dehydrated for various reasons, and antibiotics that are damaging to the kidneys, such as sulfonamides, gentamicin, streptomycin, etc., should be used sparingly or prohibited.
VI. Traditional Chinese medicine treatment.
Chinese medicine has rich experience in the treatment of kidney disease, and the use of evidence-based treatment can play a positive role in the treatment of diabetic nephropathy. However, it should also be used with caution when entering the uremic phase.
VII. Dialysis treatment.
Patients entering end-stage renal disease have many symptoms, such as nausea and vomiting due to elevated urea nitrogen, obvious acidosis, hyperkalemia, heart failure, etc., which cannot be eliminated with drugs and must be treated with dialysis to improve the quality of life. Dialysis is divided into hemodialysis and peritoneal dialysis, each with its own advantages. The advantages of hemodialysis are good dialysis effect, not easy to be infected, easy to remove water from the body, and no protein loss. The disadvantages are that diabetes makes arteriosclerosis, and arteriovenous fistula is difficult to succeed; the cost of dialysis is high; the low blood pressure and rapid drop of blood osmosis during dialysis can lead to dialysis imbalance; the application of heparin can easily lead to retinal hemorrhage and vision loss. The advantages of peritoneal dialysis are that it is convenient and can be done at home; the cost of dialysis is low. The disadvantages are that the peritoneal blood vessels are sclerotic due to diabetes and the dialysis area is small, resulting in reduced dialysis effect; about 10 grams of protein is lost with peritoneal dialysis daily; abdominal infection and blockage of the peritoneal dialysis tubing can easily occur. One of these dialysis methods can be chosen according to the patient’s condition.