Microbiological examination of urine for microflora. Medical analysis of urine for culture

A urinalysis for culture is a biological test that detects the presence of bacteria, determines their type and quantity. Bacteriological analysis of urine reveals resistance to antibiotics and bacteriophages (viruses that kill bacteria). The purpose of the analysis for sowing is to diagnose infections and inflammations of the organs of the urinary system - the kidneys, urethra, bladder.

When is a bacteriological examination of urine prescribed?

Pathogenic microorganisms are the cause of urinary tract infections and inflammatory diseases of the pelvic organs.

Infectious diseases of the urinary tract include pyelonephritis, cystitis, urethritis, prostatitis. Symptoms are frequent urination, pain above the pubis, weakness, chills, discharge from the vagina or urethra. If one of the listed diseases is suspected, a bacteriological analysis of urine for culture is prescribed.

The infectious process in the bladder requires properly selected antibiotic therapy. The prescription of antibiotics is based on the results of the analysis.

The main inflammatory diseases of the pelvic organs are inflammation of the uterus (endometritis), vagina and vulva (colpitis), uterine appendages (salpingoophoritis). For diagnosis, you need to send a smear from the urethra or cervical canal for bakposev.

Seeding analysis determines:

• bacterium - the causative agent of an infectious disease;
• the concentration (titer) of microorganisms in 1 ml of the patient's urine;
• antibiotic resistance (which antibiotics the bacterium reacts to and which ones are useless against it);
• the effectiveness of therapy - an increase or decrease in the number of microorganisms in the urine;
• the percentage of a particular bacterium in the colony.

Bacteriological urine culture is prescribed as a screening during pregnancy.

What preparation is needed

Preparation for the procedure includes several limitations. The day before the collection of urine, you do not need to drink a lot. A large volume of liquid drunk will change the concentration of bacteria, and the analysis will have to be repeated.

Before passing the analysis for sowing, it is necessary to stop taking any medicines and herbal remedies that have a diuretic effect. Juicy fruits, a lot of tea or coffee - all this is prohibited.

Sowing urine for flora is collected in a special sterile container. The rules for delivery do not require the use of other containers, especially food jars.

Features of collecting urine at home

A sterile disposable container can be purchased at a pharmacy. The packaging is not opened in advance, but immediately before collecting urine. The container must not be washed or wiped, so as not to violate sterility.

Urine for bacteriological culture is collected at the first morning toilet, on an empty stomach. For analysis, an average portion of urine is required, since the microflora that is normally present in the urethra is washed off with the first portion.

Urine sampling algorithm:

• wash the genital area thoroughly with soap and dry;
• open the lid of the container without touching the inside;
• release a small amount of urine, hold the stream;
• collect urine in a container, avoiding contact with the genitals;
• close the container with a lid without touching its inside.

The jar needs to be delivered to the laboratory as soon as possible. Storing urine at room temperature allows bacteria to multiply, making culture results unreliable. The container can be stored in the refrigerator for no more than 1.5-2 hours. Freezing the sample is prohibited.

The microbiological laboratory may refuse to accept the material if the integrity of the container is violated.

For pregnant

Urine culture is mandatory at the beginning of pregnancy (10-11 weeks) and before childbirth (36-37 weeks). A gynecologist may prescribe an additional sampling for sowing with painful and frequent urination.

7-10 days before the proposed urine collection, excessively salty and fatty foods are limited. For two days, stop taking medications, herbal supplements, dietary supplements and the use of vaginal suppositories.

Bacteriological culture of urine is not done while taking antibiotics.

Before taking the urine, a thorough hygienic toilet is carried out. They are washed in the direction from the genitals to the anus, and not vice versa. A clean cotton swab is placed in the vagina.

For kids

Not all parents know how to collect urine for culture in infants.

In addition to the container, you need to purchase a special plastic bag - a children's urinal. In the morning, the baby needs to be washed, wiped and given some drinking water.

Open the package, remove the urinal and remove the protective paper from the adhesive layer. Attach a plastic bag to the child's groin.

After the bag is filled, peel it off and pour the urine into a sterile disposable container.

It is impossible to take urine for sowing from a pot - it is not sterile. It also does not make sense to squeeze the diaper and diaper.

For women

Urine for culture should not be collected during menstruation. Bloody discharge will distort the results of the analysis. After the end of menstruation, wait 2 days before collecting urine.

Two days before the proposed urine collection, stop taking any medication. This also applies to contraceptives in the form of vaginal suppositories.

After washing the genital area, a sterile cotton swab is gently placed in the vagina. This precaution prevents vaginal discharge from entering the test material.

For men

Urine sampling by men for bacterial culture is carried out according to general recommendations. Try only to prevent contact of the genitals with the container, so as not to violate the sterility.

How much urine to collect

In order for the microbiological laboratory to be able to examine the culture of urine for microflora, 10 ml of urine is required. It is not necessary to fill the container completely.

In infants, it is enough to collect 5 ml of liquid. To stimulate urination, the baby can be brought into the bathroom and turn on the tap. The sound of water causes the child to go to the toilet.

How many days is the analysis for bakposev done

In the microbiological laboratory, urine is first subjected to macroscopic examination.

One of the signs of the presence of pathogenic microflora is cloudy urine and a bad smell.

Microscopic analysis of the sample reveals the presence of erythrocytes and leukocytes. An elevated white blood cell count is a sign of infection.

The final stage is the actual bacteriological culture of urine. The required amount of liquid is placed in a special environment suitable for the growth of bacteria.

The sample is left for a day in a thermostat that maintains a temperature of 35-37 degrees. Such conditions are most suitable for the growth of bacteria. After 24 hours, a colony of microorganisms is formed, visible on the surface of the medium. If no colonies appear after a day, it is considered that no pathogenic microflora has been detected.

When a pathogenic bacterium is detected, its type is diagnosed. There are special research methods to determine the type of colony-forming microorganisms.

The next step is to test the sensitivity of bacteria to antibiotics. It takes at least 24 hours to determine resistance.

Thus, the result of a urine test for sowing is prepared for at least two days, the average time is 4-6 days.

Interpretation of urine culture results: norms and deviations

The concentration of colony-forming units (CFU) in the analysis of urine indicates the presence or absence of an inflammatory process. The number of microorganisms less than 1000 CFU in 1 ml of urine indicates the absence of an infectious lesion.

The causes of diseases are some types of pathogenic pathogens:

• Primary uropathogens. The main one is Escherichia coli (E.Coli), Salmonella. To diagnose the disease, the concentration must exceed 1000 CFU / ml.
• Secondary uropathogens - Klebsiella, Pseudomonas aeruginosa and Haemophilus influenzae, Staphylococcus aureus. The pathological amount is not less than 10,000 CFU / ml.
• Doubtful pathogens (streptococcus, acinetobacter and others). The titer must exceed 100,000 CFU/ml.

With a mixed infection, bacteriological culture of urine reveals the type of dominant microorganism. Colonies of different types of bacteria have a different appearance from each other. Additional studies are being carried out to clarify the data.

Therapy for an infectious disease is based on the sensitivity of the microorganism to antibacterial drugs, which is shown by urine culture. The results of a bacteriological study allow the doctor to choose a drug that is effective for this pathogen.

Causes of bacteriuria

Bacteriuria is the presence of pathogenic microflora in the urine. In a healthy body, the urine in the bladder is sterile. Bacteriuria speaks of an infectious process in the genitourinary system, but does not accurately determine the place of reproduction of microbes.

The causes of bacteriuria are the following diseases:

• inflammatory diseases of the bladder and urethra;
• inflammation of the kidneys - pyelonephritis;
• bowel disease;
• prostate disease in men;
• infectious lesions of the reproductive system in women;
• venereal diseases.

When determining bacteria in the urine, additional diagnostics are needed to identify the disease in the early stages. Asymptomatic (hidden) bacteriuria can be detected even in the absence of clinical signs of an infectious disease. It is observed mainly in women, especially during pregnancy. Possible complications - pyelonephritis, premature birth, the birth of a child with a small body weight.

Other causes of latent bacteriuria are immunodeficiency states, diabetes mellitus, and the consequences of urological operations.

Can the results be false

A bacteriological analysis of urine can give incorrect results if the patient failed to pass urine correctly. This leads to:

• violation of hygiene during the test;
• use of a non-sterile container;
• period;
• taking antibiotics.

False results sometimes happen due to errors in the laboratory. If an inaccuracy of the study is suspected, a re-submission of the sample for sowing is required.

Approximate prices for bacterial sowing in Moscow

Bacteriological culture of urine in Moscow costs from 500 to 2500 rubles, depending on the pricing policy of the clinic. The average cost is approximately 700-800 rubles.

Sowing on the flora and susceptibility of antibiotics is a study that allows you to identify the degree of infection of the organs of the genitourinary system.

general information

Urine culture for flora is an analysis by the method of microbiological examination of urine under a microscope. It is customary to collect it for diagnosed inflammatory diseases with a suspected infectious nature. The essence of sowing urine on the flora lies in the identification of microorganisms and the establishment of a clear connection between their presence and the development of the disease. The following are being studied:

• Types of identified bacteria, microbes and other microflora;
• Their concentration in relation to the total volume of liquid;
• Susceptibility of isolated microorganisms to antibiotics.

The last point is relevant if microorganisms with pathogenic properties are detected.

A urine culture tank with inflammation of the genitourinary organs most often detects:

• Streptococci;
• Staphylococci;
• Coli - Escherichia;
• Proteus;
• Klebsiella;
• Enterococci;
• Candida.

A tank of urine culture for flora, as an intermediate procedure for monitoring therapy, is carried out only 5-7 days after the last antibiotic intake.

General laboratory urinalysis, as well as tank culture, are procedures that have no alternative in diagnosing infections of the ureters, and especially the bladder. In a normal situation, the entire urinary tract, from the kidneys to the urethra, does not contain bacteria - the urine is sterile. If, nevertheless, a certain number of microorganisms are detected in it, this can be explained by their ingress into urine from the external genitalia. Often, the external microflora also penetrates into the urethra, so the study, almost always, shows a positive result. However, this does not mean any disease at all. If a dangerous number of microorganisms is found, they speak of bacteriuria. One of the clear signs of bacteriuria is the clear predominance of one type of bacteria in the urine, but if there are several types, then the sample is likely to be contaminated with an external infection from the skin. In this regard, quite often, a repeated study is carried out to ensure the correctness of its results. It is customary to count the number of microorganisms in a 1 ml urine sample.

In special situations, if there are doubts about the results of the analysis of the middle urine sample, and if it is impossible to determine the clinical picture of the disease clearly and unambiguously, they resort to taking a urine sample by suprapubic puncture. This method is also used when a polymicrobial infection is detected.

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Urine sampling technology for bacteriological analysis

The main condition for a reliable result is the sterility of the sample, so you should seriously consider the rules for preparing a research sample:

• The container must be sterile and tightly closed;
• Before taking the sample, the patient must perform a toilet of the external genitalia, and disinfection of the external tissues of the urethra. This can be done with warm water without antibacterial agents.
• For analysis, a middle portion of urine is needed - first, for a couple of seconds, urine is flushed into the toilet, and only then, they collect the required amount for the sowing tank;
• Having collected the required volume of liquid, the container is tightly closed, while avoiding touching its inner walls with your fingers, and sent to the laboratory.

For this study, it is customary to take morning urine, but you can take a sample throughout the day. In this case, it is imperative to follow the rule - you can take urine for analysis no earlier than two or three hours after the previous urination. Sufficient, is considered a portion of urine from 5 to 10 ml.

If there is a suspicion of tuberculosis, the analysis is carried out in the morning for three days in a row.

If the patient has a catheter, the health worker closes it by clamping it with tweezers, then sterilizes it with medical alcohol and uses a needle to collect the required amount of urine (4 ml) for the seeding tank, after which it is poured into a container and sent to the laboratory.

Be sure to ensure that, in addition to the last name and first name, the form accompanying the sample contains the time of sampling, the method used, as well as the alleged diagnosis and data on the treatment being taken.

Reference indicators

The level of development of bacteriuria is determined by the CFU indicator - the number of units forming bacterial colonies per ml of liquid.

• The identified pathogen is considered etiologically significant, even if there are no clear clinical symptoms of urinary tract infection with CFU values ​​of more than 10 5 per ml of the test fluid. This applies to both monoculture and titer;
• With pronounced symptoms of cystitis, urethritis and infectious lesions of the urinary tract, especially its upper sections, CFU are considered etiologically significant if its values ​​are from 10 2 per 1 ml. The same applies to research situations during an antimicrobial course of procedures;
• Identification of two microorganisms in infectious processes of the urinary tract under the condition of their chronic course, CFU values ​​​​of more than 10 5 per 1 ml are etiologically significant if the isolated microorganisms do not belong to the group of contaminants;
• The study is repeated if 2 or more types of microorganisms are isolated - CFU in titers of 10 4 per 1 ml. Such indicators may be due to contamination of the sample with third-party microflora.

Alternative research methods evaluate 10 3 -10 5 CFU of one type as bacteriuria or its high probability, and CFU less than 10 3 per ml are taken as a false positive result, indicating sample contamination. For women, the values ​​of CFU 10 2 per 1 ml are taken as significant evidence of bacteriuria, subject to acute dysuric syndrome.

Regarding the reliability of the results of the study of one sample, statistics show that, subject to the rules for sampling for analysis, such a probability for women is about 80% and approaching 100% for men. Tank sowing, carried out two or three times, significantly increases the degree of reliability of the result, bringing it close to 100%.

False positive results - what contributes to this?

The main errors leading to unreliable results:

• Ignoring the rules for preparing for analysis and sampling;
• Ignoring the impact of drug antimicrobial therapy, if any;
• Failure to comply with the rules for storing the sample and its untimely delivery to the laboratory. Long-term storage of urine in a warm place for more than 1–2 hours leads to active reproduction of commensals and poor growth of pathogens, which drastically distorts the results of the study.

Purpose of appointment tank seeding

Sowing urine on the flora is carried out to determine the type of microorganisms, the degree of their reproduction and the choice of drugs to combat them. Such studies are also used to control the contamination of urine after catheterization.

Bacterial culture analysis is an accurate and informative method for studying biological material.

With its help, not only those microorganisms that produced the beginning of the infectious process are detected, but their types. What the antibactogram shows when passing a urine test for sowing, let's try to figure it out further.

What is a urinalysis for culture?

In order to prescribe competent treatment, the doctor gives the patient a referral to. A study on bacteriological culture of urine is carried out in order to recognize pathogens of infectious and inflammatory processes in the bladder and urinary tract.

When a person is healthy, his bladder does not contain harmful microorganisms, that is, the one in the bladder cavity is sterile. When pathogenic microflora enters the urethra, the infection can reach the bladder area through the ascending pathways and settle there.

The kidneys filter water and fluid that is no longer needed in the body, becomes waste material and is excreted. They get into it and bacteria causing inflammation or infection in the body.

What does the method of bacterial seeding of urine show?

Under laboratory conditions, urine is placed in a special environment that is favorable for the development and growth of microorganisms. Moreover, each of the microorganisms needs its own habitat with the right acid and water balance.

If the bacteria does not spread over the surface of the urine, then the test is considered negative.

With increased reproduction of microorganisms, experts conclude positive results. In this case, the patient needs to seriously think about his health and do not delay treatment.

In order to accurately determine the type of bacteria that have settled in the human body, they conduct a number of special studies. If an infection has been found, it experiencing the effects of certain antibiotics.

Urine culture is taken in order to identify the number of pathogenic microorganisms and to establish possible drugs that can get rid of them.

In such a study, laboratory specialists are guided by the normative indicators established for medical standards.

What does a urine test for cystitis say in our article.

Indications for analysis

Urine collection for analysis is prescribed in the following cases:

• if the attending physician suspects an infectious process occurring in the bladder, kidneys or urinary tract;
• to confirm or refute the diagnosis;
• if a patient is suspected of having diabetes mellitus or tuberculosis;
• reduced immunity can also push a medical specialist to conduct an analysis;
• in order to verify the effectiveness of the selected .

Bakposev is able to identify the following pathogens:

1. If we are talking about an analysis prescribed or for people with gastrointestinal diseases, then it is possible to identify dysentery and enterococcus.
2. Chlamydia in urine.
3. Staphylococcus. These microorganisms have a detrimental effect on the body of the expectant mother.
4. gonorrhea. This analysis is carried out in those patients who have a suspicion of a sexually transmitted infection.
5. If tuberculosis is suspected, the doctor wants to identify the presence of Koch's bacillus.

The appointment of the analysis is carried out by a therapist, urologist, and sometimes a gynecologist.

This technique reveals pathological processes occurring in the urinary system in pregnant women.

In addition to cases when there are complaints of the expectant mother and an urgent analysis is needed, doctors give a referral for the procedure twice during gestation.

The same study is sometimes taken and in order to determine whether they have an infectious process in the bladder and other organs.

Analysis indicators and its interpretation

It is not difficult to decipher the analysis if you know the unit of measurement for the number of microorganisms and normal limits in which urine indicators should fit.

The results will show types of microorganisms present in urine, as well as the presence of fungi, if they are also present in urine. Additionally, drugs that can cope with these pathogens will be indicated.

(Image is clickable, click to enlarge)

In the result, the patient will find the abbreviation COE. It stands for colony forming unit and is taken to calculate the presence of bacteria in the body.

If the value of the colony forming unit less than one thousand, then treatment is not required, and the number of microorganisms living in the urine is considered a normal indicator.

If the colony forming unit reaches over one million particles, such information indicates an extensive inflammatory process or an infectious lesion of the bladder.

If the bacteria are in a slight excess of the norm, then we are talking about an inflammatory process or a focus of infection that has recently originated in the urinary tract or bladder.

Types of urine cultures

A urine culture test is performed to identify bacteriuria, that is, the presence of a certain amount of bacteria in urine, indicating an inflammatory process taking place in the cavity of the bladder and kidneys. In another way, bacteriuria is called pathogenic microflora.

Bacteriuria most often appears in diseases such as:

• bacterial sepsis;
• prostatitis;
• urethritis;
• diabetes.

Normally, urine is sterile, with the appearance of deviations from sterility - this condition is called bacteriuria.

Hemotest carried out in cases where the determination of hidden food allergens in the blood is required. Research is not required in this case.

Microflora analysis implies the definition in addition to bacteria also the presence of protozoa and fungi. Yeast can be found in the urine. Its presence indicates a severe illness, a stressful situation or malnutrition leading to such a condition.

Sometimes in urine may appear Candida fungi. The presence of this microorganism indicates improper hygiene or wearing synthetic underwear. They are dangerous because of the rapid reproduction, leading to an allergic reaction of the body.

Often, protozoa are detected in the urine, these primarily include Trichomonas vaginalis, amoebas that cause amoebic cystitis, and also chlamydia. The causative agents of protozoal diseases enter the bladder with the blood or lymph flow, and in women, the path of penetration from the anus through the urethra is possible.

If detected, it is necessary to immediately visit the attending physician, who will prescribe medications for elimination, usually these are drugs with an antiprotozoal effect.

Pathogen tuberculosis has a specific name - Koch's bacillus. It is found in the process of studying urine using the tank seeding method. With a positive result, it is necessary to contact a phthisiatrician who will prescribe a treatment regimen.

Antibactogram and its interpretation

In addition to identifying the types of pathogens, it is necessary to understand their reaction and susceptibility to various antimicrobial agents. Therefore, experts carry out an antibactogram.

An antibactogram allows you to identify a drug that can destroy pathogens and help draw up the right treatment regimen for a doctor.

Microorganisms are designated in Latin terms, and in front of them they are also marked with a Latin letter. If there is an “S” next to the pathogen, then the pathogen should be considered vulnerable to this drug. If the specialist put the letter "R", then this drug is not suitable for successful treatment.

coli in urine

Bacteria, E. coli, are present in the body and have a positive effect on the entire microflora and the digestive tract. But when this bacterium enters the cavity of the bladder and is then excreted in the urine, it signals about the presence of an inflammatory process in the urinary tract.

However, attention should be paid to the fact that with an increase in body temperature and a large number of leukocytes in the urine this is the first sign of cystitis and other inflammatory disease caused by pathogens.

If, as a result of the analysis, the patient saw the designation Escherichia coli, then he should know that this is the Latin designation for Escherichia coli. There is no need to be afraid of this, especially since only a qualified specialist can determine the degree of danger to the body.

Thus, it is necessary to contact your doctor for a decoding and further treatment regimen.

If you do not contact a medical specialist in a timely manner, then the inflammatory process and infection in the body can go from acute to chronic. This will greatly complicate further treatment and negatively affect the general condition of the body.

Why do you need an analysis for a urine sowing tank and how to collect it correctly will be told in the video clip:

Urine culture for flora is one of the main laboratory diagnostic methods used for many diseases. Very often, this microbiological study is combined with the detection of sensitivity to antibiotics for the subsequent appointment of the most effective treatment.

Indications for urine culture for flora

Urine culture for microflora is carried out in cases where there are:

• pain when urinating;
• the presence of blood in the separated fluid;
• uncharacteristic inclusions in its sediment;
• kidney disease;
• pathology of the urinary organs;
• lower back pain;
• inefficiency in the treatment of diabetes mellitus;
• kidney tuberculosis;
• frequent and profuse urination;
• verification of the effectiveness of the treatment;
• pregnancy;
• HIV, etc.

This type of bacteriological research is difficult to overestimate. In no other way is it possible to most accurately determine the presence, quantity and type of pathogen that has spread in the kidneys and urinary tract and causes a specific disease.

Urine culture is needed to determine the type of causative agent of infection of the excretory organs and the selection of effective antibiotic therapy

Urinalysis for flora reveals the presence of streptococci, staphylococci, enterococci, escherichia coli, salmonella, gram-negative microorganisms, spirochetes, proteus, klebsiella, fungus, etc. In addition, various aerobic flora are usually present in the urine. In this way, a wide range of infectious diseases can be diagnosed and successfully treated.

Usually, a urologist advises to take an analysis, who was contacted with complaints of problems in the urinary organs or a therapist who suspected kidney pathology in a patient. In addition, indicators of sensitivity to antibiotics are always of interest to the attending nephrologist, and the lack of progress in the fight against diabetes or diseases of the pituitary and adrenal glands is of interest to the endocrinologist. In cases where a general urinalysis shows significant deviations from the norm, any specialist can refer for bakposev.

Rules for collecting urine

Urine analysis for microflora must be taken in accordance with all the rules. Failure to comply with these requirements will result in inaccurate results.

First you need to toilet the genitals without the use of soap. Then you should take the middle portion of the morning urine, after thoroughly washing your hands. The isolated liquid must be placed in a sterile plastic container with a hermetically sealed lid.

If an analysis is carried out to detect tuberculosis, then urine must be collected for three consecutive days.

The urine collection container for bacteriological culture must be sterile.

The day before, it is required to exclude from the diet foods that can affect the color of urine. These include beets, lactic acid and confectionery products containing dyes, vitamins, etc.

It is necessary to stop taking any medications, except those approved by the attending physician or not subject to withdrawal. It is necessary to collect urine for sowing no earlier than ten days after the course of antibiotic treatment.

Douching should not be done for three days before this. Also, you can not take the analysis during menstruation.

In cases where urine is collected from a bedridden patient with renal insufficiency or urinary tract obstruction, it should be collected through a catheter. To do this, it is blocked with a clamp and at least four milliliters of liquid is removed from it by means of a needle, placed in a container.

Urine must be delivered to the laboratory no later than two hours after its release.

When submitting the collected analysis, the nurse, the administrator of the medical center or the laboratory worker must inform:

• the exact time of urine output;
• how it was collected;
• possible diagnosis;
• medications taken.

Deciphering the results

If you take the analysis correctly, then reliable data will be obtained, allowing the doctor to prescribe the most effective treatment. It is very important to accurately identify quantitative indicators, since in the normal state, urine already contains a number of opportunistic microorganisms. These include streptococci, staphylococci, diphtheroids, etc. If their titer is low, then they are not able to cause a disease.

But with adverse effects on the body, they are able to go into a virulent state, provoking the occurrence of various pathologies in a person. Most often this happens due to a sharp decrease in immunity in chronic diseases, tumor processes or the development of HIV.

Deciphering the results of the analysis is of great importance for the diagnosis. Typically, reference values ​​include certain indicators. The unit of measure for sowing on flora is CFU. It is a single living microbial cell causing the growth of a visually identifiable colony of a specific microbial species. If their number does not exceed 1000 CFU / ml, then this is the norm, that is, the data obtained correspond to the usual values. This figure indicates an accidental introduction of bacteria.

Each patient receives a detailed transcript of urine culture

If these figures are more than 105 per 1 ml of urine, then it can be stated that the causative agent of the disease is considered to be identified.

In cases where there are pronounced signs of kidney or urinary tract disease, a microorganism can be considered isolated during urine culture, the titer of which is about 102 per 1 ml.

When several groups of pathogenic bacteria are found, their level should also correspond to at least 105 per 1 ml. If pathogens from these groups are detected, but their indicators are relatively low (104 per 1 ml), then the study must be done again, as this may indicate violations of the rules for collecting urine.

Additional data can be obtained by determining sensitivity to antibiotics. In this case, a whole range of different antibacterial drugs from different pharmacological groups is used to the identified pathogen. Then the microbiologist evaluates the degree of death of the colony under their influence or the absence of any action. This is done in order to avoid side effects in the treatment of these drugs, as well as to increase the effectiveness and efficiency of treatment.

It should be borne in mind that the answer from the laboratory will not come earlier than in a week, since the culture of microorganisms must still germinate on a nutrient medium, and subsequently a test for sensitivity to antibiotics will be made.

The analysis collected correctly and on time allows the patient to fully restore health.

It is known that microorganisms, despite their “small growth”, also have food “addictions”, an optimum temperature, in general, an environment that suits them perfectly, where they feel comfortable and good, and therefore begin to multiply and grow intensively.

Bacteriological inoculation or, as it is commonly called in short - tank inoculation, is used to obtain a large number of microbes of the same species (pure culture) in order to study their physicochemical and biological properties, in order to then the obtained data can be used for the diagnosis of infectious diseases.

Unfortunately, even now popular, and other methods, the main drawback of which are false positive or false negative results, cannot always identify the pathogen. In addition, they are not able to pick up targeted antibacterial drugs. A similar problem is solved by a sowing tank, which is often not in a hurry to appoint, referring to the fact that, for example, it is slowly cultivated, and the cost of analysis is considerable. However, health is worth it!

Conditions needed for food and breathing

Microbiologists now know that each pathogen needs its own "native" environment, taking into account its pH, redox potentials, viscosity, humidity and osmotic properties. The environments can be soft and hard, simple and complex, universal and not very versatile, but in all cases they must provide nutrition, respiration, reproduction and growth of the bacterial cell.

example of microorganism growth after tank inoculation into a nutrient medium

Some media (thioglycol, Sabouraud) are suitable for a wide range of microorganisms and are called universal. Others are intended only for certain species, for example, pneumococcus and Staphylococcus aureus, producing hemolysins, grow on blood agar, which serves to isolate particularly "capricious" and, at the same time, dangerous strains. Thus, there are many varieties of media, where each of them grows its own range of microorganisms.

The purpose of cultivation of microorganisms and its significance for diagnosis

In addition to water, air, soil, containing various microorganisms in various concentrations, including those that bring disease (pathogenic), many branches of medical science are interested in microbes living on the skin and mucous membranes of the human body, which can be represented by:

• Permanent residents, not carrying any danger to man, that is, the normal microflora of the body, without which we simply cannot live. For example, the disappearance of bacteria that live in the intestines and participate in the process of digestion leads to dysbacteriosis, which is not easy to treat. The same happens with the disappearance of the vaginal microflora. It is immediately populated by conditionally pathogenic microorganisms, gardnerella, for example, which cause;
• conditionally pathogenic flora, which is harmful only in large quantities under certain conditions (immunodeficiency). The aforementioned gardnerella is a representative of this type of microorganisms;
• The presence of pathogenic microbes which are not present in a healthy body. They are alien to the human body, where they accidentally enter upon contact with another (sick) person and cause the development of an infectious process, sometimes quite severe or even fatal. For example, a meeting with pathogens is still all right, at first it is treated, but (God forbid!) It will release cholera, plague, smallpox, etc.

Fortunately, many of them have been defeated and are currently "behind seven seals" in special laboratories, but humanity at any moment must be ready for the invasion of an invisible enemy capable of destroying entire nations. Bacteriological seeding in such cases plays, perhaps, the main role in the identification of the microorganism, that is, the determination of the genus, species, type, etc. (toxonomic position), which is very important for the diagnosis of infectious processes, including sexually transmitted diseases.

Thus, sowing methods, like nutrient media, are different, however, they have the same goal: obtain a pure culture without impurities in the form of microbes of other classes, which live everywhere: in water, in the air, on surfaces, on a person and inside him.

When is a sowing tank appointed and how to understand the answers?

The name of the microorganism and its quantity

Patients do not prescribe bacteriological analysis for themselves, this is done by a doctor if he has suspicions that the problems of a patient presenting various complaints are associated with the penetration of a pathogenic pathogen into the body or with increased reproduction of microorganisms that constantly live with a person, but exhibit pathogenic properties only in certain conditions. Having passed the analysis and after some time having received an answer in his hands, a person is lost, and sometimes even frightened, when he sees incomprehensible words and designations, therefore, in order for this not to happen, I would like to give a brief explanation on this issue:

When examining biological material for the presence of pathogenic microorganisms, the answer can be negative or positive (“bad sowing tank”), since the human body is only a temporary shelter for them, and not a natural habitat.

Sometimes, depending on what material is to be inoculated, you can see the number of microorganisms expressed in colony-forming units per ml (one living cell will give the growth of a whole colony) - CFU / ml. For example, inoculation of urine for bacteriological examination normally gives up to 10 3 CFU / ml of all detected bacterial cells, in doubtful cases (repeat the analysis!) - 10 3 - 10 4 CFU / ml, with an inflammatory process of infectious origin - 10 5 and above CFU /ml About the last two options in colloquial speech, at times, they are simply expressed: "Bad sowing tank."

How to "find control" on a pathogenic microorganism?

Simultaneously with the sowing of the material in such situations, the microflora is sown for sensitivity to antibiotics, which will give a clear answer to the doctor - which antibacterial drugs and in what doses will “scare” the “intruder”. Here, too, there is a decryption, for example:

• The type of microorganism, for example, the same E. coli in the amount of 1x10 ^ 6;
• The name of the antibiotic with the designation (S) indicates the sensitivity of the pathogen to this drug;
• The type of antibiotics that do not act on the microorganism is indicated by the symbol (R).

Bacteriological analysis is of particular value in determining sensitivity to antibiotics, since the main problem in the fight against chlamydia, mycoplasma, ureaplasma, etc. remains the selection of an effective treatment that does not harm the body and does not hit the patient's pocket.

Table: Alternative example of tank culture results showing effective antibiotics

Proper preparation for bacteriological analysis is the key to a reliable result

Any biological material taken from a person can be subjected to bacteriological analysis.(skin, blood, semen, mucous membranes of the oral cavity, respiratory and urinary tract, gastrointestinal tract, organs of vision, hearing and smell, etc.). Most often, the sowing tank is prescribed by gynecologists and urologists, so you should dwell on it a little.

Proper preparation for bacteriological culture will be the key to the correct result, because otherwise, the analysis will have to be retaken and wait for the appointed time. How to donate blood for sterility from a vein is the task of health workers. As a rule, nothing depends on the patient here, he simply provides an elbow bend, and the nurse takes it into a sterile test tube in compliance with all the rules of asepsis and antisepsis.

Another thing is urine or from the genital tract. Here the patient must ensure the first stage (fence), following the prescribed rules. It should be noted that the urine of women and men is somewhat different, although in the bladder of both sexes it is sterile:

• In women, when passing through the urethra, a small number of non-pathogenic cocci can be captured, although in general, it often remains sterile;
• For men, things are somewhat different. The anterior part of the urethra can supply passing urine with the following:
  1. diphtheroids;
  2. staphylococci;
  3. some non-pathogenic gram-negative bacteria, which will be shown subsequently by bacteriological analysis.

However, if they are in an acceptable concentration (up to 10 3 CFU / ml), then there is nothing to be afraid of, this is a variant of the norm.

To avoid the presence of other microorganisms and to ensure the sterility of the material taken as much as possible, a thorough toilet of the genital organs is performed before the analysis (the entrance to the vagina in women is closed with a cotton swab - protection from the ingress of the separated genital organs). For analysis, an average portion of urine is taken (the beginning of urination into the toilet, approximately 10 ml of medium serving in a sterile jar, ending in the toilet). Patients need to know: urine taken for culture must be processed no later than two hours when stored no higher than 20 ° C, so you should consider the time for transportation.

In addition, the material for the seeding tank, if necessary, is taken from the urethra and rectum in men, from the urethra, rectum, vagina, cervix and cervical canal - in women, but this happens in a medical facility where the patient should arrive. Washing, douching and the use of antiseptics in such cases is prohibited.

Other issues of concern to patients

Many patients are interested in how many days the analysis is done. It is impossible to answer this question unambiguously, it all depends on what material is being studied and what pathogen should be looked for. Sometimes the answer is ready in 3 days, sometimes in a week or even 10-14 days, since some samples require subculture to another medium.

Do not bypass the people heading to the sowing tank and the question of the price of the analysis. The approximate cost in Moscow is about 800 - 1500 rubles. Of course, it can be higher and depends on the breadth of the bacteriological search spectrum. You can probably take an analysis for free during pregnancy at the antenatal clinic, or at the clinic for special medical reasons.

For pregnant women, the seeding tank is mandatory, it is given 2 times(when registering and at 36 weeks), while a swab is taken not only from the genital tract, but also from the mucous membranes of the nose and throat. The object of search in this case, in addition to urogenital infections, will be Staphylococcus aureus (Staphylococcus aureus), which in the postpartum period can cause a lot of trouble (purulent mastitis, etc.). In addition, pregnant women are required to do urine culture, scraping of the vaginal epithelium and smears from the cervix and cervical canal.

Many women, before going to the procedure, are very afraid of such terrible words and begin to think: “Is this necessary? Maybe don't go." We hasten to assure that the tests are absolutely painless. A smear from the cervix and cervical canal is taken with a sterile cytobrush, causing absolutely no pain to the woman, but subsequently the sowing tank from s / m and s / c will protect both the expectant mother and the fetus from possible complications. The object of search during pregnancy are the causative agents of chlamydia, urea- and mycoplasma, yeast-like (usually Candida albicans), and other opportunistic and pathogenic microorganisms.

Video: demonstration video on tank culture from the cervical canal

Special cases of particular interest to those taking tests

Once in the genital tract, pathogenic microorganisms, after a very short time, are mastered and begin their harmful activity. For example, always pathogenic gonococci (Neisseria), which are the culprits of a rather unpleasant disease called and related to STDs, feel “at home” literally on day 3. They begin to actively multiply and boldly move up the genital tract, capturing more and more new territories. Everyone knows that gonorrhea is now well treated and almost no one is afraid of it. But first you need to find it. The main method of searching for this infection is tank seeding, cultivation, identification by Gram staining, microscopy.

Found in a smear taken "on the flora" from the genital tract, lying in pairs "coffee beans" (diplococci), do not indicate the presence of a sexually transmitted disease. Such a microflora of the vagina often appears in postmenopause and does not mean anything bad. A smear taken under non-sterile conditions on a glass slide and stained with methylene blue or Romanovsky (cytology) cannot differentiate the microorganism. He can only assume and refer the patient for additional research (obtaining an isolated culture).

It should be noted that if scraping from the mucous membranes of the urinary tract, taken for sowing on ureaplasma, is not such a rare occurrence, then doctors themselves often avoid sowing urine, since it is more difficult to work with it.

It creates difficulties in diagnosis, which brings great harm not only during pregnancy. In addition, chlamydia causes many diseases that are common not only to women, but also to the male population, so it is sown, cultivated, studied, sensitivity to antibiotic therapy is determined and, thus, it is fought.

During pregnancy, bacteriological culture is generally difficult to do without, since many microorganisms, masked in a cytological smear, can be missed. Meanwhile, the effect of some STD pathogens on the fetus can be detrimental. In addition, it is much more difficult to treat a pregnant woman, and prescribing antibiotics “by eye” is simply unacceptable.

Seeding methods

To isolate pure cultures of pathogens, at the first stage they resort to their inoculation on appropriate media, which is carried out under special (sterile!) conditions. Basically, the transfer of material to the environment is carried out with the help of devices used back in the 19th century by the great Louis Pasteur:

• bacterial loop;
• Pasteur pipette;
• Glass rod.

Of course, many tools have undergone changes over the 2 centuries, plastic sterile and disposable ones have replaced them, however, the old ones have not remained in the past, continuing to serve microbiological science to this day.

The first stage of obtaining colonies requires compliance with certain rules:

1. Sowing is carried out over an alcohol lamp in a box pre-treated with disinfectants and quartz treatment, or in a laminar cabinet that ensures sterility in the working area;
2. The health worker's clothing, gloves, and environment must also be sterile, since the opposite prevents isolation of isolated strains;
3. You need to work in boxing quickly, but carefully, you can’t talk and be distracted, while you need to remember about personal safety, because the material can be contagious.

Isolation of strains and study of pure cultures

The isolation of strains is not always the same, since some biological media that are in the human body require an individual approach, for example, hemoculture (blood) first in a liquid medium (ratio 1: 10) is “growth” a little, since blood (undiluted) can kill microorganisms, and then, after a day or more, subcultured on Petri dishes.

Sowing urine, gastric lavage and other liquid materials also has its own characteristics, where in order to obtain a pure culture, the liquid must first be centrifuged (aseptic conditions!), And only then sow, and not the liquid itself, but its sediment.

Cultivation and cultivation of colonies is carried out on Petri dishes or placed first in a liquid medium poured into sterile vials, and then isolated colonies are sown again, but on slant agar and the material is placed in a thermostat for a day. After verifying the purity of the resulting culture, the strains are transferred to a glass slide, a smear is made and stained according to Gram (most often), Ziehl-Neelsen, etc., and for differentiation, the morphology of the microbe is studied under a microscope:

• The size and shape of the bacterial cell;
• The presence of capsules, flagella, spores;
• Tinctorial properties (the ratio of the microorganism to staining) *.

* The reader has probably heard of such a pathogen as pale treponema? This is the causative agent of syphilis, and therefore its name (pale) appeared because it does not perceive paint well and remains slightly pinkish when stained according to Romanovsky. Microorganisms that do not perceive aniline dyes are called gram-negative, and perceiving - gram-positive. Gram-negative bacteria are given a pink or red color by Gram staining with additional dyes (magenta, safranin).

Tank sowing can be called an ancient analysis, but its popularity does not fall from this, although modern bacteriology has the ability to isolate not only strains, but also a single cell from it, which is called clone. However, to obtain a clone, a special device is needed - a micromanipulator, which is not available in conventional laboratories, since it is used mainly for research purposes (genetic studies).