Urinalysis: types and interpretation of results
In addition to the main clinical analysis of urine, special samples are used that more closely examine the individual functions of the urinary system and are assigned to diagnose certain diseases.
The most commonly used to date are:
- urine analysis for Zimnitskiy;
- three-cup sample;
- sample of Sulkovich;
- bacteriological test for sterility;
- method Addis-Kakovsky.
Consider these methods of diagnostics in more detail.Table of contents: Recommended reading:
Assay in Zimnitskiy
Urine test in Zimnitskiy allows to evaluate the concentration ability of the kidneys.It is used in addition to clinical analysis of urine.
Indications for use:
- acute and chronic renal failure;
- suspected of having chronic glomerulonephritis;
- clinical manifestations of chronic pyelonephritis;
- additional diagnosis of diabetes insipidus;
- chronic heart failure and hypertension.
Note: analysis is necessary for assessing kidney activity, not for diagnosing.
Normally, the kidneys excrete urine, which contains high concentrations of slags and protein-exchange products.These include urea, creatinine, uric acid, glucose isomers, protein substances, other substances in small amounts.The concentration indices are units of relative density of urine.
The aim of the sample is to determine the specific gravity of the elements and compounds in the urine during the daily cycle, since the indices vary at different time intervals.Dynamic observation of them allows you to draw conclusions about the activity of the kidneys.
Normally, the density of urine is in the range of 1003-1035 g / l.The higher the density, the more dissolved organic compounds it contains.
Analysis of Zimnitsky reveals daily urine volume, density at different times of the day, the amount of excreted urine at different time intervals.These data allow us to draw conclusions about violations of the kidneys.
Relative density is determined in different portions of urine, which are collected every three hours throughout the day.
Urine collection method for analysis according to Zimnitskiy
- 8 clean glass jars( cans);
- paper and handle for fixing the amount of liquid drunk.
The first morning portion is not taken into account.Then the fence is taken every three hours, only 8 times.Each portion is evaluated separately.The amount of three-hour urine on average is from 50 to 300 ml.
Rules for the collection of urine:
- The first collection of urine is conducted from 9.00 to 12.00, then every three hours: until 3 pm, 6 pm, 9 pm, 4 pm, 3.00, 6.00, 9.00( last portion).
- Jars with contents are placed in stages in the refrigerator for storage.
- After filling, the cans are delivered to the laboratory.
- A record is given for the analysis of the amount of fluid taken.
In one jar, the patient urinates, if necessary, several times within the prescribed time interval.If there were no calls for 3 hours, the can is left empty.If for 3 hours there was not enough capacity of "planned" dishes, then fill in the additional one and mark it.
Please note: should not take diuretics on the eve of delivery.It is also necessary to consult a doctor about the possibility of combining the sample with other medications.ASD10ASASD
Decoding of the results of the Zimnitsky sample
The laboratory evaluates the total amount of urine, as well as a separate amount in batches, the density of each serving, as well as daily diuresis( from 6 am to 6 pm), and diuresis( from 6 pm, Before 6 am)
Normally diurnal diuresis prevails over night.Morning density of urine above 1.018 is characteristic for normal concentration ability of kidneys.
The physiological density boundaries are between the values of 1001 - 1040. With the usual drinking regime, the density is - 1012-1025.
In the case of an unchanged specific gravity of urine, a condition called isostenuria occurs.The meaning of hypoisostenuria is in the diagnosis of diseases. With it, the density is lower than 1012-1014 g / l.Occurs when the renal tubules are unable to concentrate the urine filtrate.It occurs in all types of kidney failure.The opposite state - hyperisostenuria , is characterized by a high specific gravity, it is registered with poisoning with heavy metal salts, hyperparathyroidism, diabetes mellitus.
The analysis of Zimnitskiy is able to identify such conditions as:
- Hypostenuria .At a density below 1012 g / l, which is observed in all portions, it can be concluded that the ability of the kidneys to concentrate.This condition is typical for chronic pyelonephritis and glomerulonephritis, amyloidosis of the kidneys.It also develops in chronic heart failure, accompanied by hypertensive disease, with diabetes insipidus.
- Hyperstenuria. The density of urine is higher than 1035 g / l.This type of deviation is characteristic for diabetes mellitus, with blood diseases caused by its destruction( hemolysis, anemia), in gestosis( toxicosis of different terms of pregnancy), and also occurs in some forms of glomerulonephritis.
- Polyuria is an condition in which the urine volume is more than 1,500-2,000 ml.This deviation can also be fixed when more than 80% of the liquid taken in the day is released in the urine.Polyuria occurs in the development of renal insufficiency, sugar and diabetes insipidus.
- Nocturia. Occurs when the nighttime urine prevails over the daytime.This deviation occurs with heart failure.Nocturia can occur with increased drinking regimen.In this case, the density will be reduced.If at least in one portion the value of 1020 g / l and above is fixed, then one should not think of a violation of the concentration function of the kidneys.Normally, the daily urine volume is about 65-70%, and the night time - 30-35%.
- Oliguria. Reduction of daily urine less than 1500 ml.This condition is caused by heart failure, neglected stages of renal failure.
The study is used to determine the location of inflammation in the genitals and bladder.The method is obsolete and is used in rare cases when it is impossible to conduct more modern studies.
Analysis is carried out in the morning, before eating food and liquids.Before taking urine, the toilet of the external genitourinary organs is needed without the use of detergents.On the eve of preparing three clean cans marked( 1,2,3).Urine is collected sequentially in three vessels: the first( 1) - a small part, the second( 2) - the main and the third( 3) - the remainder.
The collected material is immediately delivered to a laboratory where it is examined under a microscope to determine the content of red blood cells and leukocytes.
Analysis of the three-glass sample
Detection of leukocytes and / or red blood cells:
- in 1 portion - typical for the presence of inflammation in the urethra;
- in 2 portions - for inflammation in the bladder;
- in 3 portions - for the inflammatory process in the bladder, prostate, kidney;
- in all portions - is typical of inflammation of the kidneys or mixed pathology.
With this method, the urinary content of calcium is determined.The index of the content of this mineral is important in the additional diagnosis of rickets.This assay can also be used to control and correct the child's dose of vitamin D.
The sample is administered by injecting a sick Sulkovich reagent containing oxalic acid into the urine, resulting in a cloudy precipitate when interacting with calcium.
Urinalysis technique for Sulkovich
The urine is collected in a dry and clean container.Before collecting urine, a thorough toilet of the genital organs is performed.A small amount of urine is released in a trickle into the toilet bowl, the remainder is collected in a jar.
On the eve of the test, do not take mineral water, milk, greens, spirits, coffee, otherwise the sample may give distorted results.Within 3 days before the test is submitted, a restriction of eating foods rich in calcium( nuts, beans, etc.) is required.
Decoding of the result of the Sulkovich test
By the degree of turbidity, the result is scored in points( from 0 to 4):
- 0 баллов - urine clear - calcium in urine none - hypocalcemia .
- 1-2 points - slight turbidity - normal result.
- 3-4 points - severe turbidity - hypercalcemia .
In some laboratories the result is assessed as pluses.
The sample has an inaccurate result, and if necessary is supplemented with a biochemical blood test.
The study is prescribed for suspected thyroid disease( hypo-hyperthyroidism), vitamin D abuse, for the detection of tumors that produce calcium.
Urine bacteriology for sterility
The examination is conducted to assess the purity of urine, and also to detect a specific type of pathogen.The same method can determine the sensitivity of microbes to antibiotics.
Urine, flowing through the internal mucous membranes of the urethra, washes away mucus and microorganisms located on them.Bacteriological study allows you to determine the presence of the pathogen and its number.
For the study, 5-7 ml of morning urine collected only on an empty stomach, after the perineal toilet is needed.The second portion is used.
Urine is placed in vessels with nutrient media, and after a time, the grown up colonies of microorganisms are evaluated.
Decoding of bacteriological analysis of urine for sterility
The result is evaluated according to the following data:
- The number of detected colonial microorganisms up to 1000 corresponds to the presence of normal flora.
- From 1000 to 10000 - there is a conditionally pathogenic flora capable of causing an inflammatory process.
- More than 100000 - in the urine pathogenic microorganisms, there is an acute inflammatory process.
In case of growth of a colony consisting of different elements, the infection is considered chronic.In complex cases, additional identification of the pathogen is carried out by repeated seeding on special nutrient media.However, this supplement lengthens the time of diagnosis, but at the same time specifies the type of antibiotic used.
These methods are simple, available for use in any medical institution and have proven themselves in a large number of people.
Allows you to diagnose kidney infections by counting red blood cells, white blood cells and cylinders in the urine.
- renal polycystic;
- kidney stones;
- chronic renal failure.
In practice, a simplified method of this analysis is used, the collection of which takes 10 hours.In the evening, a liter clean pot is prepared, the last urination is offered to the patient at 22.00.At night, the toilet should not be walked, otherwise the results of the analysis will be distorted.In the morning, the toilet of the genitalia is performed, and at 8.00 the bladder will be emptied into cooked dishes, the collected material is immediately delivered to the laboratory.
Decoding of the results of urine analysis by the Addis-Kakovskiy method
Evaluation of the results is normal:
- of leukocytes up to 2 million;
- of erythrocytes up to 1 million;
- cylinders up to 20 thousand.
An increase in these indicators indicates a pathological process.
The described methods at the present stage are replaced completely or partially by new methods, but have not lost their relevance due to their simplicity, availability and cheapness.However, they remain informative and accurate.
Vladimir Plisov, medical reviewer