Kidney tests are a comprehensive blood test performed to diagnose kidney pathologies, analyze kidney function, identify joint diseases, muscle, endocrine glands, to monitor the dynamics of the disease and monitor the effectiveness of the therapy.
Kidney tests
Kidney samples are taken for three main indicators, determined in a standard study of renal tests, - levels of creatinine, urea, uric acid. The kidney is unable to effectively remove these substances, and therefore their concentration in the plasma is increased, allowing to draw a conclusion about the development of renal pathology.
Indications
Blood test for renal tests is prescribed in cases of the development of the following diseases, symptoms or conditions:
- Kidney disease of any severity and at any stage( pyelonephritis, glomerulonephritis, renal failure) - to monitor the performance of the kidneys.
- Presence of such symptoms as regular increase in blood pressure, pulling pain in the lumbar region, headaches, "temperature jumps", edema of the face - in order to exclude the likely development of acute inflammation.
- Diabetes mellitus - in time to reveal a complication - renal failure.
- Renal pathology in close relatives - for the purpose of early detection of a possible disease that is hereditary
- Pregnancy is for mandatory monitoring even in the absence of symptoms of kidney pathologies.
- Use of medications that damage the kidney's substance or interfere with its functioning.
What shows?
The goal of the three basic kidney samples is early detection of kidney disease and inadequate release of urine from metabolic products, which is observed in many diseases.
The three basic metabolites that are the subject of the study are:
- Creatinine is a substance that is of particular importance for cellular energy metabolism in muscle tissues where it is released from myocytes( muscle cells) and transported to the kidneys from which it is excreted as urine. When the kidney is affected, the ability to actively remove creatinine weakens, and it accumulates in the blood. Since the amount of the substance depends on the ability of the kidneys to excrete it in the urine, then its level is assessed by their condition, diagnosing the development of acute inflammation.
- Urea is a product resulting from the breakdown of proteins. By its number in the blood assess the excretory capacity of the kidneys. Deviations more often indicate the presence of diseases that last for a long time.
- Uric acid, completely excreted in the urine, is a substance that appears when splitting complex nucleotides. Its increase in blood is detected with the development of diseases that are accompanied by renal insufficiency.
Preparing for the analysis of
To minimize the chance of a kidney test error, it is necessary to eliminate the factors that could affect the result and follow certain rules:
- For 12 to 14 days before taking samples, the medication is not taken( Corticotropin, Cortisol, Thyroxine, Methylprednisolone) and diuretics( Furosemide, Lasix).If this condition is not feasible, the name and doses of pharmacological agents are indicated in the laboratory for renal tests.
- For 4 - 5 days before taking the shelter observe an uncomplicated diet, limiting heavy fried, fatty dishes.
- For 1 - 2 days exclude smoking, alcohol, tiring physical stress.
- The interval between morning sampling and eating is usually 10 to 12 hours. In this case, drinking water is allowed.
- It is advisable to rest for 15 minutes before donating blood.
- Before taking blood to small patients( up to 5 years) it is necessary to drink unsweetened water( about a glass) for half an hour in small portions.
Samples, depending on the capabilities of the laboratory, are prepared for 24 - 36 hours.
Explanation of the results
Renal blood sample - a quantitative type of study with the output of the result in the form of digital data, presented in the form of a range of normal values (reference).
Norm
The range of numerical values of the" norm "for renal samples is defined in international units - micromole per liter( μmol / L).
The following measures are considered to be the norm:
| Men | Women | Children under 15 | Newborns up to 28 days | Infants up to the year | |||
|---|---|---|---|---|---|---|---|
| Urea( urea) | 2.8 - 8.1 | 2.1 - 6.7 | 1.8 - 6.7 | 1.8 - 5.1 | 1.4 - 5.4 | 12 - 48 | 21 - 55 |
| Uric acid( uric acid) | 210-420 | 140-350 | 140-340 | 140-350 | 140-340 | 143-340 | 120-340 |
Abnormality
If the ability of the kidneys to excrete metabolic products in the urine is disrupted, they accumulateI'm in the blood, and then their number grows in it. Deviation from the norm( increased or decreased concentration in the plasma of each metabolite) indicates the likely development of specific diseases.
Elevated or decreased creatinine indicates:
| Increased content of | Reduced amount of |
|---|---|
Prolonged insufficient kidney function in protracted pathologies:
| Decrease in muscle mass with prolonged immobilization, amputated limbs, muscle tissue dystrophy; |
| The defeat of hepatocytes( liver cells) with heavy metal toxins, narcotic drugs, drugs, spoiled products; | Severe liver disease, including cirrhosis; |
| Diabetes mellitus; | Fetal bearing( 1 term); |
| Congestive failure of myocardium; | Cachexia( malnutrition); |
| Myasthenia gravis( pathological muscle weakness); | Use of glucocorticoids; |
| Myositis( inflammation of the muscle tissue); | Ration with a small amount of meat( vegetarianism). |
| Hypercorticism( Itenko-Cushing syndrome); | |
| Serious kidney dysfunction in acute form, arising from life-threatening infections, with massive loss of blood, burns, pain shock, severe dehydration, eclampsia, cancers, low blood flow, ureteral overlap( stone, foreign body); | |
| Diseases of the endocrine system - hyperthyroidism, gigantism, acromegaly; | |
| Reperfusion syndrome( with limb ischemia and after vascular surgery); | |
| Damage of a significant mass of muscle tissue( with the syndrome of compression, fall, accidents, blockages); | |
| Leptospirosis( canine fever); | |
| Therapy with drugs that destroy kidneys, such as: Enalapril, Tetracycline, Aspirin, Ibuprofen, diuretics, glucocorticoids, antibiotics of the group of cephalosporins, aminoglycosides, penicillins, allopurinol, anticancer drugs. |
The physiological abnormality towards the increased concentration in the blood is found out: with a meat diet, excessive sports loads, the use of anabolics based on creatine, old age and active growth in the puberty period.
The following pathologies are possible in the event of abnormal urea:
| Downgraded indices | Increased amount of |
|---|---|
| Pathologies with elevated creatinine, including all forms of jade; | Cirrhosis, hepatitis of different origin( viral and alcoholic); |
| Hemolytic anemia; | Malignant tumors; |
| Conditions in which blood supply to the kidneys is difficult, such as heart failure, massive burns, shock; | Diseases of the digestive system that interfere with the absorption of protein amino acids:
|
| Diseases in which abnormally high protein digestion is observed: cancer, thyrotoxicosis( abnormally high production of thyroid hormones); | |
| Activation of nitrogen exchange processes; | |
| Bleeding in the stomach, intestines( upper divisions) during perforation of neoplasms, ulcers; | |
| Adrenal insufficiency due to decreased circulation of blood in the kidney; | |
| Dehydration against a background of exhaustion, infections, diarrhea. |
An increase in urea indices not related to diseases is observed with a protein-rich diet;prolonged starvation, when the muscle proteins the body uses as a source of energy against the background of their active cleavage, which leads to an increase in the production of urea;elderly age.
Deviations from the norm of indicators of uric acid indicate:
| Downgraded indices | Elevated indices |
|---|---|
| Gouty arthritis; | Alcoholism; |
| Acute forms of tuberculosis, pneumonia, scarlet fever; | HIV, Wilson's disease; |
| Inflammation and renal dysfunction, including chronic insufficiency; | Large area burns, tumor pathology; |
| Pathologies of bile ducts, liver; | Severe toxemia of 1 trimester; |
| Diabetes mellitus; | Pregnancy after 32 weeks; |
| Urticaria, eczema, psoriasis; | Menopause Period; |
| State of acidosis - acid-base imbalance with marked increase in acidity; | Child and adolescence due to active consumption of proteins |
| Toxicosis up to 32 weeks of gestation; | |
| Neuropathic anorexia, fasting; | |
| Blood cancer, anemia due to B12 deficiency; | |
| Alcoholic, food, medicinal, chemical poisoning; | |
| Increased thyroid activity, parathyroid gland dysfunction; | |
| Furosemide, thiazides, preparations containing acetylsalicylic acid, levodopa, nicotinic acid, methotrexate |