Analysis for bacteriuria. Laboratory screening for urinary tract and kidney infections. Urine culture for bacteriuria

Urine analysis for the degree of bacteriuria needed to determine the presence of pathogenic bacteria in the urinary tract. Normally, in humans, urine in the urinary tract is sterile, but microorganisms can enter the urine from the perineum and lower third of the urethra without causing inflammation. A urine test to determine the degree of bacteriuria is prescribed to all patients with inflammatory diseases urinary tract. All microorganisms, according to their ability to cause infectious diseases are divided into:

• Pathogenic (should not be normal, capable of causing disease)
• Non-pathogenic (normally present in the body and do not cause disease)
• Opportunistic (normally released in small quantities, they begin to actively reproduce under certain conditions)

By analyzing urine for the degree of bacteriuria, the doctor identifies the presence of infectious inflammation and prescribes the necessary treatment.

This analysis allows us to identify the level of bacteriuria and determine the cause of inflammatory diseases urinary tract, as well as to monitor the cure after treatment.

Method

The sector sowing method is used. With this method, the test material (urine) is placed on a nutrient medium, then the number of microbial cells in 1 ml is determined. the material being studied.

Reference values ​​- norm
(Degree of bacteriuria, urine)

Information regarding the reference values ​​of indicators, as well as the composition of the indicators included in the analysis, may differ slightly depending on the laboratory!

Norm:

• No bacterial growth detected - normal
• Bacterial growth detected - 10 3 CFU/ml - such bacterial growth does not usually cause an inflammatory process
• Bacterial growth of 10 4 CFU/ml was detected - this result is usually assessed as doubtful, it is recommended to repeat the analysis
• Bacterial growth of 10 5 CFU/ml was detected - such bacterial growth usually causes the development of an inflammatory process

Indications

• Inflammatory diseases of the kidneys and urinary tract
• Control after treatment, 5-7 days after discontinuation of antibiotics

Increasing values ​​(positive result)

• An increase in values ​​indicates the presence of an infection in the urinary tract. An assessment of the degree of pathogenicity of the identified microorganism and its relationship with the presence of inflammatory changes is carried out by a doctor, taking into account clinical data

Lower values ​​(negative result)

• A decrease in analysis values ​​indicates a negative result and the absence of an inflammatory process

A urine culture test (bacteriological examination) is used to detect bacteria in urine, select antibacterial drugs and monitor the treatment of infectious and inflammatory diseases of the pelvic organs.

To make a diagnosis, data from not only urine culture, but also other studies are usually used, and clinical signs of pathology are also taken into account.

Bacteria in urine

Infectious and inflammatory processes in the urinary tract are characterized by a recurrent course with a high probability of developing complications. The urethra and bladder are most often affected, and the infection often spreads to the ureters and kidneys. The disappearance of clinical signs of an acute bacterial infection in the urinary tract often does not indicate recovery, but the chronicity of the process, i.e. its transition to a sluggish chronic form. Inflammation and bacteriuria (presence of bacteria in the urine) remain, which helps to identify urine bacteria.

Normally, there are no microorganisms in the urinary tract, with the exception of the distal urethra, which is populated by microflora with skin perineum (in women also from the vulva).

95% of all pelvic inflammatory diseases are caused by microorganisms. The causative agents of urinary tract infections are usually Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Citrobacter, Proteus mirabilis, Serratia. In addition, staphylococci (S. epidermidis, S. aureus, S. saprophyticus), streptococci (S. pyogenes), mycoplasma (Mycoplasma), etc. become infectious agents. In uncompensated diabetes mellitus, microscopic fungi of the genus Candida are often found in the urinary tract.

Urinary tract infections are caused by pathologies in which the flow of urine is disrupted, as well as systemic diseases. In children, the elderly and weakened patients, the infectious process often occurs in a latent form or has nonspecific manifestations (digestion, weight loss, etc.).

To collect urine for bacterial culture, you should not use glass jars, household plastic containers, or use non-sterile disposable containers.

To determine the causative agent, bacterial culture of urine is performed. A referral for testing is usually issued by a therapist, urologist, or obstetrician-gynecologist. If necessary, the doctor will explain in detail what a urine test for bacterial culture is, what this study shows, how to collect the material, and how long the test takes. Only a specialist should decipher the result obtained.

Indications for analysis

Unlike clinical urine analysis, bacteriological analysis is not carried out for preventive purposes, but is prescribed if there are signs of a urinary tract infection. The reason for prescribing a bacterial culture of urine may be the detection of bacteria or fungi during general analysis urine. In addition, this study is usually prescribed to patients with recurrent cystitis, paranephritis, pyelonephritis, chronic urethritis, diabetes mellitus, as well as when monitoring the condition of HIV-infected patients, etc. Urine analysis for bacterial culture is a mandatory test that is carried out for pregnant women; in 3–10% of cases, asymptomatic bacteriuria is determined.

Urine for bacteriological analysis is taken before the start or 7–14 days after completion of antibacterial therapy (control study), unless other conditions are specified by the attending physician.

Preparing for a urine test for bacterial culture

There are a number of rules for preparing for donating urine for bacteriological examination, compliance with which allows you to obtain the most reliable result.

In acute infectious and inflammatory processes, a monoculture is usually isolated against the background of bacteriuria high degree, and in chronic cases – associations of microorganisms against the background of low-grade bacteriuria.

Women should not donate urine for bacterial culture during menstruation and for two more days after its end, since menstrual discharge, which is highly likely to get into the collected material, will affect the result of the study. It is also not recommended to use contraceptives or medications in the form of vaginal suppositories two days before the test. Douching should not be done before taking material for analysis.

Rules for collecting material for analysis

Before collecting urine, thoroughly clean the external genitalia without using antibacterial soap. To prevent urine contamination, men are advised to thoroughly rinse the penis and the fold of the foreskin before collecting material. For the study, it is necessary to collect the average portion of the first morning urine (that is, the initial and last portions are flushed down the toilet). Urine is collected in a special sterile disposable container, which is given to the laboratory before the analysis or purchased at the pharmacy. Some laboratories can purchase a transport tube containing a preservative (usually boric acid). When collecting urine, you should not touch the inner wall of the container.

Material for bacteriological research infants collected using a urine bag, which can be purchased at a pharmacy, and then poured into a sterile container.

To collect urine for culture, you should not use glass jars or household plastic containers, since it is usually not possible to ensure the sterility of such containers at home. In addition, non-sterile disposable containers should not be used.

The material must be delivered to the laboratory no later than two hours after collection.

Normally, there are no microorganisms in the urinary tract, the only exception being the distal urethra, which is populated by microflora from the skin of the perineum.

Analysis result

The main task of the analysis is to identify microorganisms in urine and determine their etiological role. The type of infectious agent, the degree of bacteriuria, the detection of microorganisms in repeated studies, etc. are taken into account.

Bacterial culture of urine is carried out on nutrient media using a bacteriological loop, swab or spatula. Normally, there is no growth of microorganisms; signs of microbial growth indicate the presence of a bacterial infection in the urine, i.e. bacteriuria.

The degree of bacteriuria allows for differential diagnosis of the infectious process from contamination of urine with normal microflora. Thus, bacteriuria up to 10 3 microbial cells in 1 ml of urine usually indicates the absence of an infectious-inflammatory process and, as a rule, is determined in the case of urine contamination; with bacteriuria 10 4, the result is questionable and there is a need for a repeat study; 10 5 or more - infectious and inflammatory process.

In order to control the therapy, the change in the degree of bacteriuria is assessed; its decrease indicates the effectiveness of the drugs used. However, when deciphering a urine test for bacterial culture, it should be taken into account that in some cases (during antibacterial therapy, low pH values ​​and/or specific gravity urine, impaired passage of urine, etc.) a low degree of bacteriuria can be determined in the presence of a pathological process. For this reason, the identification of infectious agents found in urine is also important (repeated isolation of bacteria of the same species usually indicates the presence of infection).

Unlike clinical urine analysis, bacteriological analysis is not carried out for preventive purposes, but is prescribed if there are signs of a urinary tract infection.

The detection of a monoculture or association of microorganisms in the urine is of diagnostic importance. In acute infectious and inflammatory processes, a monoculture is usually isolated against the background of high-grade bacteriuria, and in chronic ones, associations of microorganisms are usually isolated against the background of low-grade bacteriuria.

In addition to identifying the infectious agent, a urine culture test can determine the antibiotic sensitivity of isolated strains of microorganisms.

To make a diagnosis, data from not only urine culture, but also other studies are usually used, and clinical signs of pathology are also taken into account.

Video from YouTube on the topic of the article:

Laboratory testing of urine has become commonplace for every person. When going to the clinic to hand over a jar full of material for analysis, people behave differently. Someone is worried while waiting for the result. And someone carelessly forgets to visit the medical facility again to find out whether the test results are normal. And it’s completely in vain, because testing for the presence of bacteria in the urine makes it possible to promptly identify disorders of the genitourinary system. This means it’s time to start treatment.

Urine is produced by the kidneys and is a waste product resulting from the filtration of blood. It is eliminated from the body by the urinary system.

The filtration process occurs in the kidneys. This is a paired organ weighing about 150 grams. The small size does not at all prevent the kidneys from fulfilling their daily requirement for purifying the blood. And this amounts to no less than 1700 liters.

From the renal pelvis, fluid flows through the ureters into the bladder. From there it is released into the environment. It is during the excretion of urine through the urethra that many bacteria enter it.

But it also happens that inaccuracy during the analysis may arise due to improper collection of material. How to carry out the procedure correctly?

We strictly follow the instructions

To obtain a reliable result, urine collection is carried out in the morning. Before this, a thorough hygienic treatment of the external genitalia is carried out.

Urine should be donated for testing in special sterilized containers. You can buy them in pharmacy chains. An average portion of urine of 10 ml is sufficient for laboratory analysis.

If the results of the study indicate the presence of a bacterial infection, then it is advisable to repeat the urine test.

How the research is carried out

And now the treasured container ends up in the laboratory. The collected material is placed in a special nutrient medium and left for a certain period of time.

Bacteriological culture of urine is considered negative (or normal) if colonies of bacteria have not formed in it. If the laboratory assistant detects bacteria or fungi in the bacterial culture, the result is recorded as positive.

The next step in research will be to determine the susceptibility of microorganisms to medications. Typically this process takes 5-7 days.

A transcript of the test results will contain information about the detected bacteria, protozoa, and fungi. To prescribe effective antibacterial treatment, the laboratory technician will indicate medications that effectively destroy the identified type of microorganisms.

Who to contact if you have problems

The presence of pathogenic microorganisms in the urine may indicate that the body is affected by one of the serious ailments:

• pyelonephritis;
• nephrosclerosis;
• cystitis;
• urolithiasis disease;
• urinary tract tumors.

Detection of the disease on early stage becomes the key to successful treatment. Therefore, if you experience any of the following symptoms, go to the hospital immediately.

• Painful urination, accompanied by pain and burning.
• Back pain in the kidney area.
• Urinary incontinence.
• Unpleasant and pungent odor of urine.
• Swelling of the lower extremities and face.
• Presence of blood in stool.

In some cases, the disease can occur without any discomfort. A person can only find out about the existence of bacteria in urine by seeing the transcript of the analysis. The absence of body signals about the disease is interpreted as asymptomatic bacteriuria.

It is believed that in the presence of single microorganisms, the disease is not dangerous, and normally the body will be able to cope with it on its own. But people with weakened immune systems, pregnant women and children should be under constant medical supervision to avoid complications.

Only a doctor can establish the causes of the disease and make the correct diagnosis. Which specialist should I contact?

1. The therapist prescribes an initial examination and refers the patient to undergo tests. Treats mild renal tissue diseases with antibacterial and painkillers.
2. A nephrologist specializes in kidney diseases. The nephrologist prescribes specific treatment, the main goal of which is to stop the progression of renal failure.
3. Urologists are surgical specialists. They perform open surgeries on the kidneys and genitourinary organs of men. Very often the cause of kidney disease, infertility, sexual problems Only a urologist can eliminate it.
4. A nutritionist prescribes a diet for patients with kidney problems. The specialist also gives advice on how to normalize your diet.

Bacteriuria during pregnancy

During pregnancy, a woman's resistance to disease decreases sharply. A decrease in immunity during such a crucial period is considered normal, so doctors pay a lot of attention to the health of the pregnant woman: every month the attending physician writes out a referral for a urine sample.

In the case when the transcript of the analysis contains information about the presence of bacteria, and the pregnant woman does not experience any discomfort, we can talk about asymptomatic bacteriuria.

If treatment for urinary tract inflammation during pregnancy is not started on time, then the prognosis for the further course of the disease will be completely disappointing. The cause of many dangerous complications can be microbes that are found in the urine of a pregnant woman.

• Purulent form of acute pyelonephritis.
• Acute cystitis.
• Fetal hypotrophy.
• Premature birth.
• Inflammation of the membranes.
• Stillbirth of the fetus.

Therefore, all doctor’s prescriptions for pregnant women are mandatory. A timely urine test will help detect the disease at an early stage. This means that it will enable the doctor to prescribe special therapy in a timely manner that will preserve health. expectant mother and the long-awaited baby.

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It has been established that microbes do not penetrate from the blood into the urine through intact kidneys [Ryabinsky V.S., Rodoman V.E., 1969, etc.]. Bacteriuria refers to the presence of bacteria in freshly released urine due to an infectious-inflammatory process in the organs of the urinary system or the genitals of a man.

However, the presence of microbes in the urine does not allow us to talk about bacteriuria, since in approximately 10% of healthy men and women microflora grows in the anterior section of the urethra. Therefore, bacteriuria caused by an inflammatory process in the urinary tract must be distinguished from urine contamination by the microflora of the urethra.

The ideal method for detecting bacteriuria is to obtain urine for examination by suprapubic capillary puncture of the bladder.

Determination of the degree of bacteriuria

In children early age and newborns, bacteriuria should be considered when there are 10 2 -10 3 microbial bodies in 1 ml of urine [Mikhailova Z.M., 1982]. The degree of bacteriuria can be determined by urine culture, sediment microscopy, and using chemical reagents.

Gould method

The loop is fired again and 4 strips are passed through the 1st sector to the 2nd, then in a similar way with a sterile loop from the 2nd sector to the 3rd Petri dish is placed in a thermostat at a temperature of 37 ° C for 18-24 hours, after which it is assessed results on the number of bacterial colonies in various sectors of the Petri dish. The advantages of this urine culture over the usual one are its cost-effectiveness, the ability to determine the degree of bacteriuria and at the same time obtain the growth of isolated colonies necessary for further bacteriological research.

Gutman and Naylor proposed to determine the degree of bacteriuria by immersing a glass plate resembling a glass slide, coated on both sides with agar, in the patient’s urine and then incubating it in a thermostat for 18-24 hours at a temperature of 37 0 C.

The pharmaceutical company "Orion" (Finland) has improved this method research, after which it found wide application in clinical practice under the name “Urikult”. A special plate, coated on both sides with a nutrient medium, after immersion in urine, is placed in a sealed plastic container and incubated for 18-24 hours. The degree of bacteriuria is determined by comparing the number of grown microbial colonies with the data on a special scale.

In a number of patients with leukocyturia, when urine is cultured on a regular nutrient medium, there is no growth of microbial colonies. In this case, they talk about the so-called aseptic pyuria. This may be due to several reasons: 1) the presence of L-forms of bacteria and protoplasts; 2) lack of microbial growth due to intensive antibacterial therapy; 3) the presence of an inflammatory process caused by specific microflora, mainly tuberculous mycobacteria, chlamydia, viral infection or fungi such as Candida. This requires special urine tests to identify pathogens.

The number of bacteria in different sectors of a Petri dish depending on the degree of bacteriuria [Ryabinsky V.S., 1965]

Microscopy of urine sediment

Both slides and coverslips are kept in a mixture of alcohol and ether, from which they are removed immediately before use. The preparations are examined under a microscope, preferably using a bright-field phase-contrast device (FK-4) or a dark-field phase-contrast device (MFA-2) at a magnification of 800 times (objective 40, eyepiece 20). The content of bacteria in 1 ml of urine can be determined using the table developed by V.S. Ryabinsky and V.E. Rodoman (1965).

The results of determining the degree of bacteriuria by microscopy of urine sediment showed that persistent reliable results, similar to the results of urine culture, can be obtained only when there are 10 4 or more microbes in 1 ml of urine. There are difficulties in counting the number of microbes with severe leukocyturia due to the content in the urine large quantity nuclei and granules of destroyed leukocytes, as well as determination of coccal flora, primarily staphylococci, which are easily mistaken for particles of urine sediment. In these cases, intravital staining of microbes is carried out according to the method of M. N. Lebedeva (1963).

An aqueous solution of methylene blue is poured onto a clean glass slide and allowed to dry. Then the glass is wiped with a clean, dry gauze cloth until the paint deposit on it takes on a light blue tint. A drop of urine sediment is applied to this glass and covered with a coverslip. In this case, the bacteria take on a blue color; they are easier to see and determine their shape. With phase-contrast microscopy, microbes stained with methylene blue are bright crimson in the center with an even, clear rim of dark blue around the circumference, which allows them to be distinguished from other pathological impurities.

Nitrite test

The Griess reagent, as modified by Ilosvay, consists of two solutions: A - 0.5 g of sulfanilic acid dissolved in 150 ml of 30% acetic acid; B - 0.1 g of alpha-naphthylamine dissolved in 20 ml of warm distilled water. The solution is brought to a boil and filtered. The filtrate is supplemented to 150 ml with 30% acetic acid. Then both solutions (A and B) are mixed with each other and stored in a dark container, since the reagent is unstable. The test for nitrites is carried out as follows. Take 3 ml of Griess-Ilosvay reagent and add 1 ml of the patient’s urine to it with a sterile pipette.

If the test is positive, a persistent bright red color immediately appears. The nitrite test is not positive in the absence of microbes in the urine and relatively rarely becomes positive when there are less than 10 4 microbes in 1 ml of urine. Thus, the nitrite test makes it possible to easily and quickly detect the high degree of bacteriuria observed in urinary tract infections.

TTX test

Dissolve 750 mg of TTX in 100 ml of a saturated solution of dibasic sodium phosphate (Na2HPO4) - stock solution. Take 4 ml of the main solution of TTX and add a saturated solution of Na2HPO4 to 100 ml. Both solutions are sterilized by filtration through a Seitz filter and stored in the dark and cold, since TTX is sensitive to light and heat. The stock solution is stable for 2 months; worker - 2 weeks Every 2 weeks prepare a fresh working solution of TTX. The degree of bacteriuria with TTX is determined as follows. Add 0.5 ml of TTX working solution to 2 ml of urine in a sterile test tube, mix well and incubate in a thermostat for 4-6 hours at a temperature of 37 0 C.

With significant bacteriuria, the urine turns red. It should be remembered that when the content is less than 10 4 and especially 10 3 bacteria in 1 ml of urine, the formation of triphenylformazan and the staining of urine red is very insignificant or absent. That's why this test should be used primarily to detect significant bacteriuria.

Braude test

The test, as a rule, is positive only when there are 100 thousand or more microbes in 1 ml of urine. If hematuria is present, this test should not be performed, since it will be positive due to the presence of red blood cells in the urine. Thus, simplified and accelerated methods allow us to speak with confidence about a high degree of bacteriuria (100 thousand or more microbes in 1 ml of urine) and, consequently, about a purulent-inflammatory process in the kidneys or urinary tract.

The content of bacteria in 1 ml of urine, according to microscopy of centrifuged urine sediment [V.S. Ryabinsky, V.E. Rodoman, 1965]

However, a high degree of bacteriuria is not observed in all stages of acute and especially chronic pyelonephritis (on average in 60-70% of patients). In some cases, a patient with chronic pyelonephritis may have only a few thousand microbes in 1 ml of urine. In these cases, bacteriuria can be detected by determining the bacterial content in the initial and middle portions of urine [Ryabinsky B.C., 1969]. The most convenient method for this purpose is the simplified method of urine culture according to the Gould method.

If urine is contaminated by the microflora of the urethra, the growth of bacterial colonies will only be in the first Petri dish, or the number of colonies in the 2nd Petri dish will be significantly less. In contrast, during the inflammatory process in bladder and the overlying parts of the urinary tract, the number of microorganisms will be approximately the same in both the initial and middle portions of urine. Besides, this technique allows you to determine the causative agent of pyelonephritis with mixed flora of urine.

Automated methods for detecting bacteriuria

These methods for detecting bacteriuria are based on determining the bacteria themselves or their metabolites, waste products in nutrient media. According to the detection principle and registration method, they can be divided into photo- and conductometric, electrochemical, colorimetric, gas chromatographic, bioluminescent, radiometric, etc.

The main disadvantage of accelerated methods for determining bacteriuria is the fact that reliable results are obtained only with high titers of bacteriuria (more than 10 4), therefore they are indicated only for general medical examination of the population.

Determining the source of bacteriuria

Antibody-coated bacteria are detected in urine by immunofluorescence. Bacteria that carry antibodies are clearly detected by fluorescent microscopy of urine sediment. After adding antiserum to human γ-globulin labeled with fluorescein isothiocynate, a distinct fluorescence appears surrounding the bacterial cells.

Determination of sensitivity of urine microflora to antibacterial drugs

These methods are complex, time-consuming and uneconomical. In this regard, simplified, accelerated methods for determining the sensitivity of urine microflora to antibacterial drugs have been developed and introduced into clinical practice. V.S. Ryabinsky (1967) used the TTX test for these purposes. It is based on the reduction of colorless water-soluble TTX into red triphenylformazan under the influence of dehydrogenases formed during the growth and reproduction of bacteria.

If the microorganisms contained in the patient’s urine are sensitive to the test antibiotic or antibacterial drug, then the metabolism and growth of bacteria are delayed and the reduction of TTX to triphenylformazan does not occur. Depending on the sensitivity of microbes to the antibacterial drug, there is a varying degree of inhibition of the vital activity of microbes and, consequently, the intensity of the formation of triphenylformazan and the coloring of urine red. The technique can be applied even to those antibacterial drugs for which there are no standard paper disks.

Urine is collected from the middle portion during spontaneous urination or bladder catheterization. 2 ml of urine is poured into sterile tubes and 0.5 ml of TTX working solution is added. Then, one or another antibacterial substance is added to each of the test tubes, except the first (control), in the amount necessary to create a certain concentration in the urine. The tubes are shaken to mix the contents and placed in a thermostat for 6-9 hours at a temperature of 37 °C, and then the results are assessed.

The complete absence of redness in the urine indicates high sensitivity, less intense redness compared to the control tube indicates weak sensitivity, and more intense redness indicates favorable conditions for the development of microbes in the presence of this antibacterial drug. V.E. Rodoman (1976) developed a method for semi-automatic determination of the sensitivity of urine microflora to antibacterial drugs. Its essence is as follows.

Before pouring it into Petri dishes, add a certain antibiotic or antibacterial drug to the molten agar at a dose of 5-20 units or 10-30 mcg per 1 ml of medium. To quickly determine the sensitivity of urine microflora, another TTX solution is added to the nutrient medium at the rate of 2 ml of working solution per 10 ml of nutrient medium. Urine from 7 patients is poured into separate wells of a special metal Petri dish. Then, using strips of filter paper (1.2x0.9 cm) fixed in a special stamp, the urine of all 7 patients is simultaneously transferred to the agar surface in certain sectors of the Petri dish.

The Petri dish is placed in a thermostat for 18 hours at a temperature of 37 0 C. When a TTX solution is added to the agar, the result of the study can be assessed after 9 hours by the color of the medium in areas of future growth of microbial colonies. The absence of microbial growth in sectors with the addition of a certain antibiotic or antibacterial drug in the presence of microbial growth in the control Petri dish indicates a high degree of sensitivity of the urine flora to this drug.

Yu.M. Feldman and M.S. Melnik (1981) proposed a simple and effective method determining the sensitivity of urine microflora to antibiotics, based on the ability of pathogenic and opportunistic bacteria to decompose glucose, thereby changing the pH of the environment. To prepare the nutrient medium, add 4 g of Endo agar to 100 ml of distilled water and boil for 3-5 minutes. Glucose (1 g per 100 ml) is added to the hot medium. The medium is poured into Petri dishes, which can be stored in the refrigerator for 5-7 days.

The test urine is centrifuged for 5 minutes at 3000 rpm and 1 ml of urine is left in the test tube along with the sediment. The sediment is mixed with the remaining urine and distributed evenly over the surface of the cup. After contact for 5-10 minutes, the urine is drained, the cup is dried for 20-30 minutes, and disks with appropriate antibiotics or antibacterial substances are placed on the surface of the medium. Results are assessed after 3 1/2-5 hours.

When microbes multiply, the environment turns red. If the microflora of the urine is sensitive to a certain antibiotic, then a transparent, undiscolored zone of inhibited microbial growth is clearly visible around the disc. The sensitivity of the pathogen to this drug is determined by its diameter: diameter up to 10 mm - the microflora is insensitive; 11-15 mm - slightly sensitive; 16 - 25 mm - sensitive; more than 25 mm - highly sensitive.

The disadvantages of the method include the impossibility of determining sensitivity to antibacterial drugs when the content is less than 50 thousand microbial bodies in 1 ml of urine, as well as the lack of standard disks with some antibacterial drugs.

The main disadvantage of accelerated methods for determining the antibiotic sensitivity of microorganisms is that they work not with pure cultures of microorganisms, but with native material, which is used only in severely ill patients before obtaining the results of inoculating a pure culture.

Detection of pathogens of a specific infection

Tuberculous mycobacteria

When examining urine for tuberculous mycobacteria, one should take into account the fact that relatively little of it is excreted in the urine and a small amount is usually found in morning urine. Therefore, for the study, the morning portion or urine excreted by the patient during the day is collected. If the result of bacterioscopy of a regular smear is negative, the urine is examined by flotation.

Chlamydine

One method for isolating chlamydia is based on the use of chick embryo yolk sacs, the other is based on isolating chlamydia in cell culture. S.I. Solovyova and I.I. Ilyin (1985) used three methods for laboratory diagnosis of chlamydia: identification of the morphological structures of microorganisms in scrapings from the urethra using Romanovsky-Giemsa staining, determination of chlamydia antigens in scrapings from the urethra using direct fluorescent antibody staining modifications (MPFA) according to the generally accepted method and isolation of microorganisms in cell culture 929. In their opinion, for a more reliable and reliable analysis of clinical material, the integrated use of both methods is necessary: ​​isolation in cell culture and indication of chlamydia when staining scrapings using the MPFA method.

In recent years, the method of DNA diagnostics of pathogens of a specific infection, based on the use of polymerase chain reaction, has become widespread.

ON THE. Lopatkin

The term bacteriuria means the presence of microorganisms in the urine that are detected during laboratory testing. According to the generally accepted classification of diseases (ICD-10 code), bacteriuria is designated by code N.39.0, which means infection of the urinary tract without establishing a specific location. Normally, the contents of the bladder are considered sterile, i.e. the presence of bacteria is a pathology that requires further examination.

Bacteriuria

Even the minimal presence of microorganisms in urine is considered pathological.

The main indicators for detailed studies are:

• number of bacteria per 1 ml of urine;
• genus of microorganisms.

Therefore, regardless of age group and human status (pregnant woman, infant, elderly person, etc.) the presence of any type of bacteria in the urine is a pathology. The main cause is inflammatory diseases of the kidneys or urinary tract (ureters, bladder, urethra).

In children, especially young children, bacteriuria most often occurs due to inflammation of the bladder. It is not difficult for a child to get a cold in the bladder, especially for little girls: just wet your feet while walking or run barefoot on the cold floor. Lack of proper hygiene affects the results of a general urine test, so it is strongly recommended that you wash your child thoroughly before collecting the test.

Women much more often than men suffer from inflammatory diseases of the bladder and urethra due to the relatively short urethral canal, in which bacteriuria is observed.

An infection in women, entering the urethra, quickly rises higher, into the bladder, where all the favorable conditions for the development of pathogenic microflora are present.

In addition, statistically every second woman is familiar with the symptoms of cystitis (acute or chronic):

• frequent acute (unbearable) urge to urinate;
• nagging pain in the lower abdomen and external genitalia (labia majora, clitoris);
• nagging pain in the lower back;
• severe burning sensation when relieving minor needs;
• change in the color of urine: the appearance of pronounced sediment, turbidity (actually bacteriuria), the presence of mucus and blood ().

It is important to understand that when collecting urine for laboratory testing, certain hygiene rules must be followed. Bacteria and various microorganisms cover the human body; the internal microflora of the vagina contains several types of microorganisms. In addition, microorganisms from the intestines (through the anus and fecal matter) can enter the urine collected for analysis. Therefore, washing (with soap or other means for intimate hygiene) is an integral part of urine analysis.

May cause asymptomatic bacteriuria. Clinical picture completely absent: the person does not complain of pain when urinating, or pain in the lower back (in the kidney area), or urinary retention. But laboratory research detect presence various types microorganisms. Chronic pyelonephritis is relatively common in pregnant women, especially if the pregnancy was unplanned (the woman did not undergo a comprehensive examination before conception).

Causes and pathogenesis

Bacteria can enter urine for a number of reasons:

1. Direct inflammatory disease kidney or urethra (primary or secondary);
2. Diseases of the intestines or rectum (constipation, hemorrhoids);
3. Inflammatory infectious diseases of the female reproductive system (ovaries, uterus, vagina);
4. Inflammation of the prostate gland (in men).

Bacteriuria is characteristic of inflammatory processes of the kidneys. Pyelonephritis, especially chronic, can be asymptomatic, but pathogenic microflora is detected during a general urine test. The path of bacteria entering the urine is obvious: the lesion is localized in the kidney, less often in both.

Inflammation of the ureter develops relatively rarely. May be caused by obstruction (blockage) of the urinary duct or pelvis, which leads to stagnation of urine. Stagnation of urine makes itself felt by a sharp nagging pain in the lumbar region, so most often people seek medical help on their own.

Inflammatory processes in the bladder are accompanied by a sharp, pronounced nagging pain. Pathogenic microorganisms develop in the cavity of the bladder, which provokes bacteriuria at the outlet (initially, urine descending from the kidneys does not have bacteriological impurities).

Infectious diseases, accompanied by inflammation and bacteriological damage, can be localized in the urethra. Urethritis is often caused by sexually transmitted diseases - chlamydia, gonorrhea, and less often - syphilis.

In men, urethritis may appear as redness of the outer edges of the urethra. In this condition, not only microorganisms are detected in the urine, but also impurities of blood, blood, and protein. Urethritis caused by gonorrhea or chlamydia may not appear in women before pregnancy, but makes itself felt at 3-5 months of pregnancy. The same applies to children in the first year of life: when passing through the birth canal, the baby “catches” harmful microorganisms, which leads to the development of the disease. The first symptoms may appear only at 2-4 months of life.

The walls of the lower intestines border the urethra and the walls of the vagina (in women). Therefore, chronic constipation (including those occurring during pregnancy), inflammation hemorrhoids(hemorrhoids), inflammation of the prostate gland (in men) can provoke the penetration of bacteria from the intestines into the cavity of the bladder and urethra. But most often, bacteriuria appears due to improper hygiene of the genital organs: along with the contents of the intestines or vagina, microorganisms enter the surface of the urethral canal (urethra), from where they seep into the urethra itself, and then upward, affecting the bladder, ureters and even the kidneys.

Ways bacteria get into urine

Kinds

There are several main classifications of bacteriuria:

1. According to the presence of symptoms: true and false (asymptomatic).
2. According to the distribution of the root cause: ascending and descending
3. By pathogen: staphylococcal, colibacillary, streptococcal, gonococcal.

The truth or falsehood of bacteriuria is determined during further examination, after the initial detection of bacteria in the urine. True is the form in which the proliferation of microorganisms occurs directly in the organs of the urinary system.

False or asymptomatic bacteriuria is characteristic of concomitant diseases and conditions such as:

• constipation;
• haemorrhoids;
• vaginitis

Ascending and descending bacteriuria is also determined after identifying a focus of inflammation. The ascending appearance is characteristic of a focus of infection located in the urethra or bladder - in this case, the bacteria seem to rise up the urethra and can cause inflammation of the kidneys.

Descending bacteriuria - characteristic manifestation pyelonephritis and ureteral obstruction, when the source of inflammation is located in the upper parts of the urinary system.

The type of microorganisms present in the urine is identified using bacterial culture. Staphylococci belong to the opportunistic microflora: millions of different staphylococci live on human skin and are capable of causing inflammation and bacteriuria only when the immune system is weakened. Colibacillary bacteriuria characterized by the presence of Escherichia coli in the urine. Such infection can occur due to pathological processes in the intestines and non-compliance with personal hygiene rules. Streptococci are often found in the urine of people who have had diseases corresponding to the causative agent:

• sore throat;
• pneumonia;
• streptococcal bronchitis;
• scarlet fever;
• periodontitis;

In this case, the penetration of streptococci into the urine is due to a sharp decrease in activity immune system. It is also possible for a child to become infected during childbirth or during sexual intercourse.

Gonococci are the messengers of gonorrhea (a sexually transmitted disease). Therefore, for those who have even insignificant amount gonococci, it is recommended to visit a venereologist and undergo the appropriate tests.
In the video about asymptomatic bacteriuria in pregnant women:

Symptoms

The symptoms of bacteriuria can be very diverse - from asymptomatic to acute pain. Bacteriuria is not an independent disease, but a clinical symptom of a number of pathological processes, often inflammatory, occurring in the body.

You can independently identify bacteriuria by observing the color of your own urine. If the urine is cloudy, has an unpleasant odor (from sour to the smell of rotten vegetables), has sediment in the form of flakes or mucus, then this is most likely how bacteriuria manifests itself.

Diagnostics

The norm is indicative - the absence of bacteria and other impurities. The presence of microorganisms is considered a pathology. In case of bacteriuria, to confirm the results, urine collection and analysis is repeated, before which the patient is advised to wash thoroughly. In a hospital setting, washing can be carried out by a nurse or orderly. It is preferable to use a sterile container to collect the material, but for general urine analysis, a clean, dry container is often used.

Rules for collecting urine for general analysis:

• Wash thoroughly with warm water and soap or other intimate hygiene products.
• An average portion of urine is collected.
• Touching the edges of the container (container) must be prevented.
• Women should not donate material during menstruation, but if there is an urgent need, a tampon must be inserted into the vagina and then washed again. In addition, the use of a tampon is also recommended for women without menstruation (during pregnancy and after menopause) to avoid vaginal discharge from getting into the collected material. Men need to expose the head of the penis by retracting the foreskin.

It is important to deliver the urine to the laboratory within an hour after collection. If you stay in a room at room temperature for a long time, your urine may change physicochemical characteristics, which will lead to false results.

For bacterial culture, it is necessary to collect urine in a sterile container, observing the above conditions. The analysis is carried out within 3-7 days by placing the material in a container (Petri dish) with a nutrient medium. Not only the presence of microorganisms is determined, but also their variety and sensitivity to various groups of antibiotics.

Treatment

How to treat the disease that causes bacteriuria depends on the type of microorganisms and their sensitivity to antibacterial drugs.

In some cases, for example with cystitis, the use of bioactive medicinal plants is a fairly effective remedy:

• bearberry;
• chamomile;
• cranberry;
• wild rosemary

In the absence of kidney pathology, drinking plenty of fluids and using diuretic herbs and drugs that help flush out bacteria are indicated:

• dill;
• parsley;
• celery (including juice).

It is very popular among women suffering from chronic cystitis and during pregnancy. natural remedy- Phytolysin. Herbal medicine can be used as a method of self-medication in children and pregnant women, provided there are no allergies or individual intolerances. Do not forget that any self-medication is a serious and responsible step, so at least consulting a doctor is necessary.

Drug therapy and dosage of the drug are selected individually, depending on the patient’s age, health status, concomitant diseases and conditions.

The following types of drugs can be used:

• Monural.
• Nolitsin.
• Sumamed.
• Nitroxoline.
• Furagin.
• Rulid.
• Furadonin.

In the treatment of gonococcal infection, ceftriaxone, ciprofloxacin, and spectinomycin are used. For pyelonephritis - 5-NOK, Palin, Loraxone, Amoxiclav.
The main drugs for the treatment of bacteriuria depending on the underlying cause