Unlike other organs in our body, the kidney is often silent when it is damaged. Most patients with chronic kidney disease may not have obvious symptoms in the early stage, or the symptoms are very mild, and when they seek medical attention when symptoms appear, they may have lost most of their kidney function, and eventually they can only maintain their lives through hemodialysis, peritoneal dialysis or kidney transplantation. How to detect chronic kidney disease early is a topic of great concern.
1.Pay attention to early signals
Chronic kidney disease can show many symptoms before diagnosis, such as fatigue, weakness, edema of eyelids, face and lower limbs, increased foam in urine, abnormal urine color, pain or difficulty in urination, increased urination at night, back pain, loss of appetite, pale face, exhalation with urine smell, itchy skin, etc. None of these symptoms are specific, but all of them may be manifested in patients with chronic kidney disease. If the above symptoms appear, you should go to the hospital as soon as possible to improve the relevant physical and chemical examination, in order to clarify the diagnosis and timely treatment.
2.Regular physical examination
Besides paying attention to early signals, regular physical examination is also the most effective way to detect chronic kidney disease. Many patients with asymptomatic hematuria, proteinuria and reduced kidney function are detected through regular health checkups. Common tests for kidney disease include urine tests, kidney function and kidney ultrasound. In addition, for kidney disease caused by hypertension and diabetes, it is necessary to rely on urine microalbumin quantification to detect early kidney damage. The following are the common tests related to chronic kidney disease in physical examination.
1) Urine routine: As a non-invasive test, it can easily, quickly and economically detect the presence of abnormalities such as hematuria, proteinuria and tubular urine, and is an important window for the detection of kidney disease. Hematuria is the presence of higher than normal red blood cells in the urine and can be seen in glomerulonephritis, urinary tract infections, stones, tumors, trauma, etc. If the hematuria is not serious, it cannot be detected by the naked eye and can only be determined by microscopic examination, which is called microscopic hematuria; when the hematuria is serious, the urine can appear washed water-like or even blood-colored, which is called carnal hematuria. Proteinuria, on the other hand, refers to protein content in the urine that exceeds the upper limit of normal, which also suggests the possibility of kidney disease. In a normal person, urine protein, urine occult blood, urine red blood cells and urine white blood cells should be negative or in the normal range of values in a routine urine test. If they appear positive or exceed the normal value, further examination is required to clarify the cause of proteinuria and hematuria.
(2) 24-hour urine protein quantification: This refers to collecting all the urine of the patient for 24 hours a day and testing the total amount of urine protein contained in it, with a normal value of <150 mg. This test is usually performed after a positive urine protein is found in the urine routine to more accurately quantify the protein in the urine. If the 24-hour urine protein quantification increases, it indicates the possible presence of kidney disease.
(3) Urine microalbumin: This test can measure an increase in abnormal urine protein that cannot be detected by routine urination, and is one of the sensitive indicators to determine early kidney damage. The normal value is <20 micrograms per minute or <30 milligrams per 24 hours, and if elevated, microalbuminuria can be identified. This test is often required for the early detection of diabetic nephropathy in patients with diabetes mellitus. In addition, it is an early indication of hypertensive kidney damage, kidney damage due to hypertensive syndrome in pregnancy, and kidney damage due to metabolic syndrome.
(4) Blood creatinine: This test is usually found on our biochemical test list and is an important indicator of kidney function. An abnormal increase in it indicates impaired kidney function.
(5) Blood cystatin C: It is an indicator to assess the early damage of kidney function, and usually appears abnormal before the blood creatinine rises.
6）Renal ultrasound: It mainly observes the size of kidney, the thickness of kidney cortex and the clarity of kidney structure, etc. Chronic kidney disease can be manifested as smaller kidney size, thinner kidney cortex and blurred internal kidney structure.
(7) Kidney ECT: It can understand the glomerular filtration function of each kidney and reflect the kidney function status more precisely.
3.Screening for high-risk groups
For high-risk groups, taking corresponding means to track and evaluate kidney condition in real time is also an important means to detect kidney disease. These people should pay attention to blood pressure, blood sugar, blood lipids, blood uric acid and other indicators, but also urine microalbumin, urine albumin/creatinine ratio and other more sensitive and accurate test items, at least once every six months to monitor urine routine, urine microalbumin and kidney function, so as to detect kidney damage at an early stage. The elderly, whose kidney function is gradually declining with age, should also have their kidney function tested once every six months.
The so-called high-risk groups include.
(1) Diabetic patients: diabetes can involve microvasculature throughout the body, including glomerular vessels. Long-term poor glycemic control of diabetes can lead to diabetic nephropathy. As mentioned earlier, such patients should have their urine checked for microalbumin in addition to routine urine tests. Microalbuminuria is confirmed if urine microalbumin is elevated in more than 2 out of 3 tests within 3 months. If the laboratory results are normal, it still needs to be rechecked once every six months to a year to closely monitor the changes of kidney condition.
(2) Patients with hypertension: kidney is one of the important target organs damaged by hypertension. If blood pressure is not controlled for a long time, about 40% of hypertensive patients will develop proteinuria, which further leads to impaired kidney function. Most of the early renal damage in primary hypertension is manifested as microalbuminuria, and the presence of microalbuminuria suggests glomerular capillary damage, as well as a poor prognosis of cardiovascular disease in hypertensive patients.
(3) Patients with metabolic diseases: mainly refer to patients with obesity, hyperlipidemia and hyperuricemia. Metabolic syndrome and its individual components such as hyperlipidemia and hyperemic uric acid are all high-risk factors for chronic kidney disease. Patients with high blood uric acid can develop gout, which also involves the kidney and is called gouty nephropathy.
(4) Family history of kidney disease: If there is a family member with a history of kidney disease, the probability of an individual developing kidney disease is 5 to 8 times higher. Therefore, if someone in the family (especially immediate family members) has chronic kidney disease, other members should also have regular kidney tests.
(5) Older people over 65 years old: As we age, our kidneys undergo different degrees of degenerative changes in both anatomical structure and physiological metabolism. Clinically, the indicators related to kidney disease in older patients will be evaluated in conjunction with the patient’s age and related changes in kidney ageing.
(6) Patients taking long-term drugs with nephrotoxicity: antibiotics, antipyretics and analgesics are the most common drugs that cause kidney damage. People should take medications in standard doses, usage or follow medical advice to avoid unnecessary damage to the kidney.
In addition to the above high-risk people going, chronic urinary tract infections, urinary tract obstruction, excessive alcohol consumption, removal of one side of the kidney or congenital independent kidney, autoimmune diseases (systemic lupus erythematosus, dermatomyositis, scleroderma, etc.), high protein diet, smoking, and patients with viral hepatitis are all high-risk groups for chronic kidney disease. These patients should also pay attention to the related symptoms in their daily life and have regular medical checkups.
In conclusion, to know whether your kidneys are healthy or not, you must go to the hospital for regular medical checkups, not based on your personal self-perception. Early detection and early diagnosis of kidney disease can be achieved with simple urine, blood and ultrasound tests, especially don’t forget the most basic urine test. Even if you already have chronic kidney disease, its development can be effectively controlled with early and active treatment.