Biochemical urine analysis: how to collect it correctly, what it shows

To carry out all the necessary tests, a special strip is used, which, after being placed in urine, acquires a certain color. There is an explanation for each shade on the back of the striped bottle. For example, when amylase in the urine increases, the test strip turns pink. This may indicate a viral infection. Urine analysis in children is performed using a similar method.

As a rule, urine biochemistry is used in terms of prevention, however, in the last few years, it has been used more and more often. Modern diseases mutate, begin to quickly develop and adapt in the human body, which complicates not only diagnosis, but also subsequent treatment.

What is urine biochemistry

The biochemistry of daily urine is not a single analysis, but a set of laboratory tests. This is a high-precision diagnostic operation aimed at studying ongoing processes in the human body. From a practical point of view, this analysis allows you to clarify or refute the diagnosis made by a specialist. Only a specialist in this field can accurately determine which tests the patient needs to undergo in order to verify the veracity of the diagnosis.

The test material is 24-hour urine, in which the concentration of biochemical substances is measured. To carry out laboratory analysis, the following factors must be taken into account:

Normal urine output per day. There is a table that shows how many liters of urine a person produces in one day based on his age group. In other words, such deviations signal problems in kidney function.
The presence of foreign elements in the urine.
The color of the urine (if blood is present, this indicates serious abnormalities).

Based on all the criteria, laboratory technicians carry out all the necessary studies and checks, and, ultimately, confirm or refute the diagnosis made to the patient. The collected material is processed for several days.

Explanation of meanings

Daily analysis, which shows the concentration of certain parameters in urine, is aimed at identifying various diseases and pathologies at their early stages of development. In a normal state of health, there should be no deviations from the norm. Interpretation of daily urine analysis for possible reasons for deviations in indicators:

Presence of ketone bodies, higher than 5 mmol/l			The patient has diabetes mellitus and pancreatitis. Other reasons: general intoxication of the body, dysfunction of the pancreas
Bilirubin level is above 5 µmol/l			Liver diseases - cirrhosis, hepatitis, gallstones. It increases if there is blood in the urine.
Amylase	above 100 units/l		Presence of cancer, hyperparathyroidism, osteoporosis
	below 100 units/l		Jade, rickets
Calcium	exceeding the norm		Osteoporosis, cancer
	demotion		Rickets, nephritis
Magnesium	above normal		Addison's disease, with renal failure
	below normal		Diabetes mellitus, kidney dysfunction, pancreatitis
Potassium	exceeds the norm		Liver disorders, dietary errors
	below normal levels		Addison's disease, pyelonephritis
Uric acid	excess		Viral hepatitis, gout, pneumonia
	demotion		Muscle atrophy, lead toxicity
Glucose above 0.05 g/l			Diabetes mellitus, adrenal gland disorders
Urea		below 330 mmol/day	Inflammation of the kidneys, glomerulonephritis, liver oncology
		above 580 mol/day	Muscle atrophy, hepatitis, diabetes mellitus, hyperthyroidism

Considering the difference between the indicators, up or down, and the extensive list of possible reasons for this, it is impossible to make an accurate diagnosis. If the normal concentration of certain substances in urine is disrupted, an additional, comprehensive examination of the patient is carried out.

Albumen

Albumin is a protein that can be present in small concentrations in urine only when a person eats a large amount of protein foods. Given this fact, it is recommended that before taking a daily urine test, you adjust your diet a few days before. A slight, constant excess of albumin may be a sign that protein metabolism is impaired or infectious diseases are present. If the albumin concentration is greatly exceeded, this is an alarming sign indicating the possible presence of malignant neoplasms.

Glucose and acetone

Determination of glucose concentration helps to identify the early stages of diabetes mellitus, pancreatitis, and thyroid diseases. Acetone is a ketone body that should not be in the urine.

The presence of acetone in small quantities may be a sign of an error in nutrition when there is a large load on the pancreas. If acetone is very high and is constantly present in the urine, this is one of the first signs of diabetes.

Microelements (calcium, sodium, phosphorus, magnesium, potassium)

A change in the concentration of microelements in the urine is an alarming symptom, indicating a number of pathological processes, mainly from the organs of the urinary and endocrine systems. An excess of magnesium most likely indicates diabetes, and an increased sodium content indicates the need to immediately consult a doctor, as liver dysfunction is possible. If phosphorus is detected in the urine, a diagnosis is made to detect kidney stones.

Determining calcium concentration allows you to identify kidney diseases and track positive dynamics during the treatment of cystitis and a number of other inflammatory diseases of the urinary system.

Urea and uric acid

Diagnosis of kidney disease includes testing the concentration of urea and uric acid. Urea is a substance that is produced during protein breakdown. It is excreted through the kidneys, and if its concentration is high, this means dysfunction of the kidneys, which cannot cope with their work.

Urea and uric acid reduce the level of ammonia that is produced during metabolic processes. A decrease in urea levels is a sign of muscle atrophy, in which there is not enough fluid, or severe intoxication of the body.

Amylase

It is an enzyme that is produced in the pancreas. Takes part in the metabolic process. If amylase levels increase, this is a sign of dysfunction of the digestive system.

Creatine

The amount of creatine varies depending on the person’s age, the degree of physical activity, and the presence or absence of any pathological processes. Reasons for creatine deviation from the norm: kidney inflammation, muscle dystrophy, iron deficiency anemia, renal failure.

Heavy metals (bismuth, lead, mercury)

These substances are detected in urine only in cases of severe intoxication of the body with heavy metals and their compounds. This diagnosis requires immediate medical attention.

Salts (phosphates, sulfates, chlorides)

The presence of salts in urine always indicates kidney dysfunction.

What does a biochemical urine test show?

What does urine biochemistry show? The essence of the study is to collect information about human life by determining the constituent biological substances in urine. These include:

amylase;
urea;
creatinine;
electrolytes.

Research conducted on the basis of collecting information about these components of urine is reliable, informative and accurate.

Express test strips for urine analysis

Rules for collecting daily urine

Most patients mistakenly believe that a laboratory urine test is a biochemical test. Laboratory analysis occurs quite quickly, but does not guarantee 100% accuracy of the results. Using this test, you can determine the individual concentration of tests in urine, including platelets and proteins.

Defined indicators

A biochemical study of 24-hour urine is prescribed to the patient by a doctor after an initial examination and anamnesis. Standard analysis includes determining the following indicators:

Presence of protein structures. An increased protein content in a daily urine sample (DBS) indicates an inflammatory process in the urinary system and metabolic disorders.
Glucose content. The presence of sugar indicates diabetes or chronic kidney disease associated with impaired glucose reabsorption.
Bilirubin. It is a bile pigment, a breakdown product of heme (a component of hemoglobin). A deviation of its concentration from normal levels may indicate obstruction of the hepatic or bile ducts.
Ketone bodies. Their appearance is associated with incomplete breakdown of fats, which occurs with diabetes or nutritional deficiencies.
Amylase. Digestive enzyme responsible for the breakdown of carbohydrates. A change in concentration indicates pathologies of the pancreas, gastrointestinal ulcer.
Uric acid. Purine degradation product. A change in its concentration indicates joint diseases and weakened kidney function.
Calcium, sodium, chlorine, magnesium ions. Typically, changes in the concentration of these electrolytes are associated with diabetes mellitus, kidney problems, and improper digestion.
Phosphorus (phosphates). An increased concentration may indicate the presence of urolithiasis.
Salts - oxalates, urates. They appear in the urine in cases of kidney disease.

The laboratory also necessarily evaluates the volume of excreted urinary fluid. Its change is associated with the functioning of the excretory organs. The color of urine depends on the content of the coloring pigment urobilin. Transparency is determined by the presence of protein. A very important indicator is the acid-base balance of urine. Its change can be caused by an inflammatory process, kidney disease, etc.

How to collect a biochemical urine test

Before filling a special sterile flask with urine, you must thoroughly rinse your genitals. Various cosmetic, as well as flavored gels, creams and shampoos should not be used for this procedure. Separate conditions for collecting daily urine from a child. Tests are collected within 12 hours, since children have an accelerated metabolism.

Various cosmetic, as well as flavored gels, creams and shampoos cannot be used until testing

The first portion of urine must be emptied into the toilet. Urine contains an increased concentration of salts, as well as foods that have been consumed in recent days. It is best to start collecting urine at 7 am. Afterwards, during the day you need to fill a sterile flask with urine, and try to do this on an empty stomach. Experts recommend avoiding eating food, as well as sweet tea and coffee, when collecting daily urine.

The next day, at exactly 7 o’clock, you need to fill the flask with urine for the last time. Even if there is no urge to go to the toilet, you need to force yourself to go to the toilet.

It is worth noting that if parents do not know how to collect daily urine from a child, they should consult with specialists.

The final action is preparing another flask, as well as transfusing the collected urine into it. The top layer, which contains a concentration of salts and other foreign elements, must be poured out (no more than 5 milliliters) and the contents of the first flask poured into an empty one. Store in a cool place until delivery. The collection of daily urine is completed, you can submit it for testing to the laboratory.

Rules for preparing for analysis

Preparing for the analysis is not difficult, but mandatory. The reliability of the results depends on strict adherence to all its rules.

A day before collecting biomaterial you need to:

stop drinking alcohol and smoking;
give up fatty and fried foods, too spicy, sour and salty dishes, as well as sweets;
exclude from the diet drinks and foods that can color urine (blueberries, beets, colored carbonated drinks);
adhere to the usual drinking regime;
stop taking antibacterial drugs and uroseptics.

It is important! Before collecting urine for analysis, it is necessary to warn the doctor about all the vitamins and medications you are taking, so that he can later correctly interpret the results.

The day before, you should take care of the availability of clean containers for collecting urine, given that one should be at least 2 liters in volume - all the urine received during the day will be poured into it, and the other - no more than 150 ml. The container is needed to send part of the collected biomaterial to the laboratory.

Containers for collecting and storing biological fluid must be sterile or cleanly washed and dry.

A tight lid is required.

An important rule in preparing to collect urine for analysis is maintaining personal hygiene . On this day, it is better to abandon special gels and use simple soap and warm water.

Norms

There is a table of standards, and it is used to determine the number of constituent particles in urine, as well as limits that should not be exceeded or, on the contrary, reduced. A list indicating the current standards for biochemical urine analysis:

Norms of indicators in urine

The daily amount of urine is no more than 1500 milliliters per day.
The density of urine should not exceed 1.1 g/l.
Creatinine. This indicator differs between men and women. For the former, the norm is considered to be from 7 to 18 mmol per day. In women - from 5.5 to 16 mmol/day.
The phosphorus content in urine is from 13 to 39 mmol per day.
Sodium – no more than 280 mmol per day.
Magnesium and calcium – 2.4-8 mmol per day.
Potassium should not exceed 100 mmol per day.
Uric acid – 1.1 g per day.
Oxalates – 8-42 mg per day.
Amylase - 10-1300 units per liter of urine.

Indicators are considered the norm for the adult category of people (from 20 years to old age).

Children have their own table of all indicators, but it is normalized from 6 months to adolescence - 14 years. It is quite difficult to say what is normal, since there are a lot of nuances in such studies. First of all, the age difference. What is typical for a baby is no longer the norm for a one and a half year old baby.