How to judge the quality of kidney?

Examination of renal function The function of the kidney is to discharge all kinds of wastes in the body into urine. Therefore, when renal function is abnormal, on the one hand, we do a urine test to see if there are too many nutrients lost in urine; On the other hand, the composition of blood can be tested to see if there is too much waste left in it. * The daily urine volume of healthy adults is about one liter, but there may be a big difference in urine volume due to the amount of drinking water and sweating. In addition, the number of urination increases, and the urine volume may not be more. Therefore, in urine examination, it is sometimes necessary to collect 24-hour urine volume to calculate the total urine volume and analyze whether the composition has changed. This kind of examination is especially important for patients with chronic kidney disease. Too much water staying in the body will cause edema. Patients with renal function problems often have edema due to the obstacles of urine production and excretion. When the daily urine volume is higher than two liters, it is called polyuria, which is an abnormal phenomenon; Its causes include drinking a lot of water, taking diuretics or suffering from diabetes insipidus. When urine volume decreases, it is called oliguria, and its disease is due to dehydration or kidney disease. When almost no urine is discharged, it is called anuria, and its causes include severe nephropathy or mechanical urinary tract obstruction (such as prostatic hypertrophy and urinary tract tumor). * Urine pH is normal. The pH value of urine is between 5 and 6.5 (blood is about 7.4). The reason why it is acidic is that the nutrients in the body decompose to produce acid, and the excess acid is discharged into urine. People who often eat fruits and vegetables sometimes have alkaline urine. When sick, urine may be acidic or alkaline, depending on the cause. * The concentration of hydrogen ions in pH solution, expressed in negative logarithm. Set pH 7.0 as neutral, less than 7.0 as acidic, and more than 7.0 as alkaline. * Urine specific gravity, excess water and urine osmotic pressure's body C are excreted through the kidney and urinary system; The discharged water and waste are combined into urine. Urine specific gravity refers to the ratio of urine to water (excluding waste). When renal function is normal, it can effectively regulate water in the body; When the water in the body is insufficient, the urine thickens and the specific gravity becomes higher. When there is too much water, the urine becomes weak and the specific gravity is low. The urine specific gravity of normal people is between 1.003- 1.030. However, a single examination is not helpful for diagnosis, and it is necessary to continuously detect and compare its changes. When suffering from diabetes insipidus, chronic renal failure and other diseases or taking diuretics, the proportion of urine is low due to increased urination. On the contrary, when suffering from dehydration, diabetes and nephrotic syndrome, the proportion of urine is high. In addition, the osmotic pressure of urine can be measured by osmometer. Healthy people are 300~ 1000 mOsm/KgH2O (osmotic pressure concentration). * When the water content in Fisher urine concentration test is insufficient, the urine thickens and the specific gravity becomes higher; If there is more water, the urine will become weak and the specific gravity will be low. When the renal function is weakened, the regulatory function of the kidney becomes worse. The following tests should be done as a reference. From the night before the examination, that is, eating and drinking were completely forbidden, which led to water shortage and repeated detection of urine specific gravity. Under normal circumstances, urine will become particularly thick, with a specific gravity above 1.025. If it is lower than this value, the concentration function of urine will be reduced. In addition, the dilution test is greatly influenced by factors other than the kidney, and it is almost not used now. * Urine protein detection The detection of proteinuria can be divided into qualitative and quantitative methods. Qualitative examination can be carried out by urine test paper, positive or negative; Quantitative examination needs to collect 24-hour urine to detect the total amount of protein and the average amount of the unit. Under normal circumstances, human urine contains almost no protein, which is negative by qualitative examination with urine test paper. The total amount of adults in one day does not exceed 100 mg. If urine protein is excreted too much, it is called proteinuria. There are many reasons for proteinuria, but proteinuria caused by kidney disease is the most common. Therefore, urine protein examination is also used as a large number of screening for kidney diseases. The so-called physiological proteinuria (standing proteinuria) is a normal phenomenon and has nothing to do with kidney disease. * Physiological proteinuria is healthy, but temporary proteinuria occurs due to strenuous exercise or posture change. The most typical example is proteinuria caused by standing state, which is called standing proteinuria. * urine occult blood test urine contains blood called hematuria. In severe cases, urine turns red, which can be judged by naked eyes. If there is a small amount of bleeding, there is no special change in the appearance of urine, which is not easy to be seen by naked eyes, so it is necessary to check the occult blood in urine. Urinary occult blood test is an examination item to detect whether it is hematuria. Hematuria can be caused by many diseases, such as calculus, infection, cancer or nephritis. During menstrual period, menstrual blood may be mixed with urine when urinating, and urine test should be avoided as much as possible during this period. * Urine sediment Urine is mixed with various solid components, separated by centrifuge, coated on a glass slide, and examined under a microscope (without staining). Under normal circumstances, a small amount of red blood cells or white blood cells, mucosal cells or crystals can be seen. General urine routine examination does not include urine sediment, but if kidney disease is suspected, you can do this examination to find out the type and quantity of cells. If there are many red blood cells, it is hematuria; When there are many inflammatory cells, it is pyuria and so on. Sometimes you can even find exfoliated cancer cells or parasites (eggs). * PSP excretion test Phenol red (PSP) is a pigment. After intravenous injection, most of it is excreted into urine through the kidney. Urinary PSP excretion was measured at 15 minutes, 30 minutes and 2 hours after injection. Normal value:/kloc-25.50% at 0/5min; When the renal function is poor, the excretion of PSP in urine will be significantly reduced. * creatinine clearance rate (CCr) The normal content of creatinine in blood is 1 mg/dl, and most of it is discharged into urine. When renal function is weakened, the excretion of creatinine acid in urine decreases, which increases the blood content. The check method of creatinine clearance rate is to measure the creatinine content in blood and urine at the same time, and calculate how much creatinine is excreted through the kidney in a certain period of time (one day or one minute). The clearance rate of creatinine acid can reflect the filtration rate of glomerulus (that is, the filtration rate of blood from glomerulus to renal tubule). The clearance rate of normal men was103 ~112ml/min, and that of women was 95~ 107 ml/ min. When the kidney is sick, the glomerular function is low and the creatinine clearance rate is also reduced. The clearance rate of creatinine acid is one of the most sensitive tests, and the serum creatinine acid content can present abnormal values before it rises. In addition, the clearance rate of other parts can be detected as a reference for diagnosis. * clearance rate The ability of the kidney to remove various substances from plasma. * Serum urea nitrogen (BUN) is the final product of protein and amino acids in blood, and its main metabolites are liver and kidney. The serum urea nitrogen content of normal people is 10~ 15mg/dl. When renal function is poor, urea is not excreted well and stays in the blood, which is called uremia. This is not only seen when renal function is weakened, but also when there is shock or massive gastrointestinal bleeding. Common diseases include end-stage renal disease and liver cirrhosis. * Serum electrolytes Blood contains various electrolytes. The main cations are sodium, potassium, calcium and magnesium. Anions include chlorine, bicarbonate and various organic acids. These electrolytes not only have the function of maintaining blood osmotic pressure, but also each ion has its unique function and is an indispensable substance for maintaining life phenomena. Most electrolytes cannot be made in the body and must be taken in from outside. Most electrolytes are excreted into urine through the kidney to maintain the balance in the body; If the balance is seriously out of balance, it may be life-threatening, so it is necessary to supplement the appropriate and appropriate electrolyte solution by oral administration or injection as soon as possible. Sodium and chlorine, sodium chloride and salt dissolve in water and decompose into sodium ions and chloride ions, which is very important for maintaining osmotic pressure. Eating too much salt is prone to high blood pressure, so pay special attention to salt intake at ordinary times. The normal value of sodium ion in blood is 136~ 149 mEg/l, chloride ion is 98 ~ 106 Meg/L, and the normal concentration of potassium ion in serum (extracellular) is 3.7~5.0 mEg/l, but the intracellular content is as high as 30 times that of extracellular. Potassium ion plays an important role in nerve conduction and muscle contraction People with heart disease and kidney disease must be careful not to take too much potassium ion. Excessive blood potassium will lead to rapid contraction (fibrillation) of the heart, or even failure of contraction, leading to cardiac arrest. The normal concentration of calcium ion in calcium serum is 9~ 1 1 mEg/dl. Most of the calcium ions in our body are stored in bones and are the main components of bones. Calcium ion is mainly regulated by parathyroid hormone, which can release calcium ion from bone tissue. Therefore, excessive secretion of parathyroid hormone will cause osteoporosis. When renal function is not good, the calcium ion discharged with urine will decrease, thus increasing blood calcium, destroying the balance between calcium ion and parathyroid hormone, and causing a vicious circle. Osteoporosis, which usually occurs in the elderly, is mostly caused by insufficient calcium intake.