Analysis for pathogenic intestinal microflora. Conditionally pathogenic and pathogenic microorganisms. Analysis of feces in children

Determine the state of the intestinal microflora in a child. Why can a doctor prescribe such a study and what should parents know about it?

Indications

Such a study is especially important for infants, who have an increased risk of developing intestinal pathology. It is also advised to make it for children who often get sick, for example, with frequent SARS.

Most often, stool analysis is done for intestinal disorders.

Kinds

1. Coprological examination of feces. He is prescribed the very first in case of suspected bowel problems. The analysis will show how food is digested in the intestines and reveal the inflammatory process.
2. Biochemical analysis of feces. Helps to identify fermentopathy.
3. Express seeding of feces. This is a quick method of research, during which the normal microflora is determined as a percentage.
4. Sowing feces for dysbacteriosis. Such a study allows us to assess the concentration and number of bacteria that are representatives of the normal microflora, as well as conditionally pathogenic flora. Feces of the child are sown on a nutrient medium. Within a few days colonies of bacteria grow, which are examined under a microscope and counted. The form indicates the number of microorganisms per 1 gram of feces, indicating the number of bacteria forming colonies (CFU). If pathogenic flora is detected, sensitivity / resistance to antibiotics is additionally determined.

Stool tests are aimed at identifying the number of different bacteria in the intestine and their ratio.

Where can you get tested?

Tests for dysbacteriosis can be taken both in public clinics and in private laboratories. At the same time, parents should remember that public medical institutions have their own opening hours and do not conduct research on weekends.

Is special training needed?

If the analysis is assigned to an infant who has begun to be fed, then three days before the study, the introduction of new products is excluded. Also, within a few days before the delivery of feces, you need to stop giving the baby any medications, including activated charcoal and anti-colic drugs.

It is also impossible to do an enema, use rectal suppositories and give the child laxatives before testing for dysbacteriosis.

How to collect feces?

A stool sample should be collected from a child who has already urinated to prevent urine from entering the test container. Also, before collecting the material, the child must be washed away.

For the study, you will need about 10 ml of the baby's feces, which is placed in a sterile container. It is best to take stool particles from different parts of the baby's stool. If there are any impurities in the feces, they are also placed in a container with feces for analysis.

Before taking feces, it is necessary to wash the genitals of the baby

How much and where can you store feces?

Feces are usually collected in the morning and taken for analysis within 1-3 hours after a bowel movement. If fresh morning feces are not immediately available, the sample container for analysis can be stored in the refrigerator for up to 6 hours. Stool storage at room temperature will distort the results of the study.

Norm values

Decryption

Most of all in the stool sample of a healthy child should be bifidobacteria. Normally, they make up about 95% of the total microflora. It is these bacteria that perform all the main functions of the intestinal microbial flora - assistance in the absorption of minerals and vitamins, the synthesis of vitamins, stimulation of intestinal motility, neutralization of toxins, and others.

No less important are lactobacilli, which also ensure the functioning of the intestine, produce lactase and protect the child from allergens. They are in a healthy intestine contains approximately 6% of all microorganisms. The normal microflora also consists of Escherichia coli (Escherichia), which help to remove oxygen and resist pathogenic flora.

Such a representative of the intestinal flora as bacteroids appear in the feces of infants older than 6 months. These bacteria help break down fats. Also in the healthy large intestine of babies, peptostreptococci and enterococci are normally found.

Normally, pathogenic enterobacteria, such as salmonella or shigella, are not detected in children's feces. Their detection does not indicate dysbacteriosis, but serious intestinal diseases. Also in the feces of the child should be absent Staphylococcus aureus and hemolytic Escherichia.

The presence of pathogenic bacteria in the feces of a child indicates the presence of an illness in a child

Reasons for deviations

• If the number of bifidobacteria and lactobacilli is reduced, and the indicators of opportunistic flora are increased, these are signs of dysbacteriosis. Also, this picture is typical for intestinal infections and pathologies of enzymes.
• The composition of the microbial flora of the intestine is also affected by malnutrition of the child. Excess consumption of fats will change the indicator of bacteroids, and an excess of carbohydrate food will affect the number of peptostreptococci and enterococci.
• A decrease in the number of typical Escherichia coli often occurs with helminthic invasions. Non-pathogenic Escherichia also becomes less with violations of feeding the child, intestinal infections and antibiotic therapy.
• An increase in the number of Escherichia coli, in which activity is reduced, indicates the initial stage of dysbacteriosis.
• An increase in the number of Candida fungi is characteristic of candidiasis.

> Sowing on pathogenic intestinal flora, determining its sensitivity to antimicrobials and bacteriophages

This information cannot be used for self-treatment!
Be sure to consult with a specialist!

The human intestine is normally inhabited by a large number of microorganisms. These are various representatives of lactobacilli, bacteroids, enterobacteria, peptostreptococci, etc. These bacteria make up the so-called intestinal microflora, participate in the digestion process, support local immunity, preventing the development of infections. Intestinal infections develop when pathogenic (disease-causing) microorganisms enter the intestinal lumen and multiply. The most common causative agents of intestinal infections are Shigella and Salmonella. Vibrio cholerae, clostridia (causing botulism, etc.), Yersinia, and Staphylococcus aureus are detected somewhat less frequently. Sowing on pathogenic intestinal flora establishes the cause of the intestinal infection, and determining the sensitivity of microorganisms to antibiotics and bacteriophages helps to choose the right therapy.

What are the manifestations of acute intestinal infections?

Symptoms and complaints vary somewhat depending on the causative agent of the infection. When infected with shigella, the onset of the disease is acute. There are cramping pains in the abdomen, the temperature rises. Characterized by frequent, painful urge to defecate, not accompanied by the separation of feces, or feces are separated in small quantities with an admixture of mucus and blood. Salmonellosis is characterized by the simultaneous occurrence of vomiting and diarrhea. The chair at the same time can be both yellowish and greenish. Soreness and rumbling in the abdomen are more pronounced to the right of the navel. All intestinal infections, accompanied by diarrhea or vomiting, lead to intoxication and dehydration. This is manifested by dryness of the skin and mucous membranes, in severe cases - a decrease in body weight.

When is seeding for pathogenic intestinal flora prescribed?

The study is prescribed by an infectious disease specialist, therapist or pediatrician in case of suspected acute intestinal infection. Sowing with the determination of sensitivity to antibiotics and bacteriophages in this case helps to identify the causative microorganism, to conduct a differential diagnosis with other diseases that have similar symptoms, and to choose the right therapy. At the end of treatment, repeated sampling of the material for sowing is required in order to control the destruction of the pathogen.

The analysis is carried out when issuing personal medical books for public sector workers (nutrition, health care, education, etc.). If a bacteriocarrier has been detected, a therapy is carried out aimed at the destruction of the microorganism, after which the analysis should be retaken.

How is the study conducted, and how to properly prepare for it?

The study is carried out without prior preparation. The material for bacteriological culture is fresh feces. It is taken into a tightly closed sterile container with a spatula. Defecation before this is carried out in a clean vessel or pot. When collecting material, it should not be contaminated with urine and secretions from the genital tract. If there is mucus and pus in the feces, it is advisable to select just such fragments of it, since the concentration of the pathogen in them is much higher.

The material can be collected from the rectum with a sterile swab. After the introduction of the tampon into the anus, rotational movements are performed in both directions, the resulting material is transferred into a sterile container.

How are the results interpreted?

Normally, when sowing, the growth of pathogenic microorganisms should not be. If growth is detected, we can talk about an acute intestinal infection or a bacteriocarrier. Determination of sensitivity to antibiotics and bacteriophages in this case will help to choose the right drug for treatment.

If there are few pathogenic bacteria in the stool, the result may be negative. An indirect sign of the presence of pathogens may be a decrease in the growth of normal flora.

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 time 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 instruments 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 flow 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 making sure that the resulting culture is pure, 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).

Intestinal infection is a common cause of indigestion in children. To quickly cure your child, you need to take tests and identify the true cause of intestinal upset. Laboratory diagnosis of intestinal infections includes an analysis of feces for a conditionally pathogenic group of microorganisms and an analysis for pathogenic flora (analysis for a disgroup and a typhoid and paratyphoid group of bacteria).

An analysis of feces for a disgroup is a study of fecal masses for the presence of pathogens of intestinal infections. This group includes bacteria that are not permanent inhabitants of the intestines in healthy children and can potentially cause an infectious process. These include the causative agents of dysentery (shigella) and salmonella.

Conditionally pathogenic microorganisms (enterococci, staphylococci, clostridia, fungi), along with "beneficial" bacteria, make up the natural intestinal microflora. They are called conditional, because. their ability to cause infection depends on specific circumstances: weakened immunity, a sharp decrease in the number of "helper bacteria" (lactobacilli, bifidobacteria), spoiled food.

In what cases it is necessary to examine the feces?

It is necessary to donate feces for a disgroup to clarify the diagnosis if an intestinal infection is suspected or as part of preventive measures.

For the development of an intestinal infection, pathogenic microbes must enter the intestines of the child. The source of infection is the feces of an infected person. Transmission of microbes can occur through contact with a sick person or a carrier of an infection, through the use of contaminated food or water. The waterway is considered the most common.

Not all bacteria manage to get to the intestines - gastric juice causes the death of most of them. Since infants (especially newborns) produce less gastric juice, they are at higher risk of infection. In infants, an intestinal infection can occur when complementary foods are added. If complementary foods are prepared without observing sanitary rules or have not undergone heat treatment, then opportunistic microbes may be present in it.

With an intestinal infection, a child may experience the following complaints:

• stomach ache;
• nausea, vomiting;
• liquid stool;
• fever, chills, general weakness.

Acute intestinal infection in children can occur in the form of gastritis, enteritis or colitis, it develops quickly. Diarrhea is a protective reaction of the body to remove the pathogen. But along with liquid and abundant stools, useful substances are also lost, and if treatment is not started on time, then dehydration develops from profuse diarrhea and vomiting. The skin and visible mucous membranes become dry, the child becomes lethargic, the amount of urine decreases, there is no sweat and tears. The newborn has a fontanel. In very severe cases, shock and multiple organ failure develop. Babies develop dehydration much faster.

The indication for analysis is the identification of carriage. These are the cases when children who have already had an intestinal infection continue to excrete a pathogenic microbe with feces. Therefore, the analysis of feces for the intestinal group for hospitalization is an indispensable procedure if the child needs to undergo surgery and treatment in a hospital for another disease.

A preventive study for the carriage of pathogens of intestinal infections is also carried out by medical practitioners, workers in the food industry and educational institutions and is included in the mandatory annual examination.

Can show if essential digestive enzymes are present in the body.

How to take an analysis? Stool collection rules

Before you donate feces to the intestinal group, you need to know how to do it correctly. The technique of taking is not difficult. Feces should be collected in a special plastic bottle, which can be bought at a pharmacy. Before taking feces, you need to prepare the child: for several days do not take activated charcoal, castor oil, do not put rectal suppositories and do not take antibiotics. They take feces after the child goes to the toilet “little by little”.

Collect feces from several places and fill one third of the container, this is about 2 cm. If you have to wait a long time for natural defecation, then feces taken from underwear (necessarily fresh) are suitable as material for analysis. A pipette can be used to collect stool if the stool is very loose. Excrement is taken from areas where there are a lot of pathological impurities, such as pus, mucus, flakes. The selected material should be free of blood. We collect feces in the morning. There are cases when taking a feces is not required, a rectal swab is sent for analysis. It is taken in the clinic with a special swab in the position of the child lying on his side. The taken feces or smear is handed over to the laboratory within 3 hours after sampling.

Laboratory diagnostics

Analysis of intestinal infection in children includes bacterioscopic and bacteriological examination of feces. The bacterioscopic method shows the presence of bacteria and protozoa in feces under a microscope. Bacteriological analysis of feces is the cultivation of a colony of microorganisms.

To do this, a stool culture tank is made on a nutrient medium. By the nature of growth, the type of infectious pathogens and their concentration are determined. When pathogenic microorganisms are detected, their sensitivity to antibiotics is determined.

The most frequently asked question is: “How long does it take to test for intestinal infections?” It takes time for a colony to grow. How many days the culture will grow depends on the specific type of microbe. Data is usually obtained within 1–2 weeks.

Sometimes the analysis of the intestinal group may not be informative enough. For example, if the cause of the infection is a virus or protozoa, or if not the pathogen itself was found in the feces, but its waste products. In this case, they donate feces for a polymerase chain reaction. PCR of feces determines the DNA of the pathogen, even if only one bacterium has entered the feces. The data comes within a day.

Additional diagnostic research methods for intestinal infections include a blood test, blood culture (if the child has a fever for more than 3 days) and serological analysis (allows to detect antibodies to pathogens).

Stool culture for pathogenic intestinal flora also helps to differentiate intestinal infection from other conditions that can cause the same symptoms. Differential diagnosis of intestinal infection is carried out with dysbacteriosis and food toxic infections. For the diagnosis of dysbacteriosis, a fecal analysis for UPF is given.

Decryption of received data

In a healthy child, there are no pathogenic microorganisms in the feces, i.e. the analysis should be negative for the disgroup and salmonellosis, as well as for the dysenteric amoeba and the typhoid and paratyphoid group. Normally, there are no such simple microorganisms as intestinal Trichomonas, balantidia.

High values ​​of pathogenic bacteria that are not part of the normal microflora are found in two cases: acute intestinal infection and bacteriocarrier.

An UPF analysis will tell you how many of these bacteria are in 1 gram of feces. Low values ​​of enterococci, clostridia, candida fungi and bacteroids are considered a negative result, because. for the development of infection, a certain amount of the pathogen is necessary, and not just its presence. If the conditionally pathogenic microflora prevails over the concentration of lactobacilli in the feces, this is dysbacteriosis.

If an intestinal group is detected, the analysis is supplemented with a test for the sensitivity of bacteria to antibiotics.

Antibiotic sensitivity is indicated by the following letter designations

• S - sensitive (h);
• R - stable, resistant (y);
• I - moderately stable (yy).

Treatment

If the stool test came back positive, then the sick child should be isolated. With a mild course of the disease, treatment can be carried out at home. It is necessary to restore the amount of fluid lost in the feces (rehydration). The doctor prescribes antibiotic therapy. In severe dehydration, the child should be urgently hospitalized!

Differential diagnosis can be difficult if one disease occurs under the guise of another. In such cases, an accurate diagnosis is established based on the results of successful treatment. If the therapy was effective, the diagnosis is correct.

It is quite simple, however, at the same time, very informative analysis - it allows you to diagnose almost all diseases of the digestive system, clarify the location of the lesion (stomach, current or colon) and detect the presence of uninvited guests - parasites and pathogenic microbes. However, most parents under the analysis of feces mean only "analysis for dysbacteriosis", which is so fond of prescribing to all babies. However, there are several analyzes of feces and microbiological seeding (“for dysbacteriosis”) is performed as the last one, when all other problems are excluded.

In children of the first year of life, fecal analysis reveals various digestive problems - disorders of the stomach. Intestines, problems with the liver and pancreas, infectious diseases and hereditary pathology of metabolism. What tests are given and what do they look at?

This analysis evaluates the main characteristics of feces - physical, chemical and microscopic, in addition, depending on the type of feeding and the age of the baby, it will have characteristic features. But in order for the analysis to show reliable data, it is necessary to collect it correctly, which in young children is a rather difficult task.
The analysis is collected from a diaper or oilcloth, since the diaper absorbs some of the liquid, and the analysis will be unreliable.

For analysis, at least 1-2 teaspoons of feces collected in a dry, clean container are required. But baby food jars should not be used - microscopic food particles remain on their bottom and walls, which will distort the result. Ideally, this should be a fresh analysis - the baby went in a big way, you collected and delivered the analysis to the laboratory. But if this is not possible, collect it in a container, tightly close the lid and place it in the refrigerator door - you can store it for a maximum of 6-8 hours.
It is unacceptable to collect material after an enema or the use of laxative products or medicines; there should be no particles of urine in the feces.

How is it assessed and what should be normal?
Consistency. For children of the first two years of life, the chair is acceptable in the form of porridge and unformed. On full breastfeeding, liquid porridge, with a little water, there may be thick sour cream. On IV, the chair can be soft sausage or gruel. With the introduction of complementary foods, the stool begins to take shape and becomes thicker, by the age of two it is usually a loose sausage. Stool in the form of "dry smoked sausage" or "sheep balls" is constipation. The chair is liquid, water with impurities and often it is constipation.

Color. In babies of the first year of life, the feces are usually yellow, with small admissible admixtures of greenery in the first 3-4 months. Then the stool becomes yellow-brown, and by the age of two it becomes about the same as in adults. Pieces of food are acceptable, especially in the first months of complementary foods, and when using bright foods, coloring of feces in the color of the product (beets, rhubarb, pumpkin).
Smell. In the first months of life, the stool of breastfed babies has the smell of sour milk, while artificial ones smell sharper. With the introduction of complementary foods, especially meat, the stool acquires the usual fecal smell.

pH (reaction). Normal is a neutral or slightly alkaline reaction, but in the first months when fed with formula or breast milk, it can also be slightly acidic.
Protein. healthy children should not have protein in the feces - its presence indicates inflammation of the intestines, the presence of mucus, bleeding, exudate, undigested food.
Reaction to occult blood. Normally, there should be no blood in a healthy intestine - this always indicates problems. Most often, blood appears with allergies, inflammation of the intestine. rectal fissures. prolapse of the rectum, hemorrhoids, polyps and malformations of the intestine.
response to bilirubin. Bilirubin is one of the breakdown products of hemoglobin, which is acceptable in feces until about three months of age, later, under the action of enzymes and microflora, it is completely transformed into stercobilin, giving a brown color. The appearance of it in the feces after this age indicates health problems.

Slime. Mucus is a jelly-like discharge that is clear or whitish in color. They are designed to protect against the aggressive effects of intestinal contents. However, normally little mucus is released, and at the exit it is completely mixed with feces. A noticeable presence of mucus in the feces is acceptable up to 3-5 months of life, especially in infants. And then they talk about the presence of an inflammatory process.
Leukocytes. A small amount of leukocytes, especially in the first months of life, is acceptable, however, if they are released in large quantities in combination with mucus and blood, this indicates inflammation and damage to the intestinal wall.

Muscle fibres. They talk about the degree of digestion of protein foods; before the introduction of meat complementary foods, they practically do not exist in a child, and in the future they should be single. If there are a lot of them, this indicates a violation of digestion in the stomach and intestines, problems with the pancreas, inflammation of the intestines.

Connective tissue. Normally, it should not be, it occurs only after the introduction of complementary foods with insufficient secretion of the stomach, problems with the pancreas.
Neutral fat. Fatty acid. Soap. In early childhood, small amounts of it may occur, but after six months it appears in violation of the pancreas, liver, or diseases of the small intestine.

Remains of undigested food. In the first years of life, the presence of plant food residues in the feces is acceptable - especially corn, carrots, apple skins, etc. If there is a lot of digestible fiber in the feces, this may indicate that food passes through the intestines too quickly. Undigested fiber may be normal.

Starch. It appears in food with the introduction of complementary foods, if there is a lot of it, it burns about the poor functioning of the pancreas, indigestion in the intestines, and intestinal infection.
iodophilic flora. These are special types of bacteria, the overgrowth of which occurs with dyspepsia (digestion disorders), disruption of the small intestine, disruption of the stomach and pancreas.

Test for carbohydrate content of feces.
This study is carried out with suspicion of lactase deficiency - a decrease in the amount of an enzyme that breaks down milk sugar (lactose) in the intestine. It is usually prescribed for dyspeptic symptoms - liquid, foamy stools, impaired weight gain that occurs when using dairy products. True lactase deficiency (when there is an enzyme deficiency) is rare. For the most part, there are false or secondary variants of lactase deficiency, when the enzyme is present, but it is either not yet ripe, or blocked as a result of an intestinal infection, or there is an overload of milk sugar (for example, with an imbalance of fore and hind milk in infants).

This condition disappears after correction of nutrition, treatment of intestinal infection and normalization of microflora. The analysis of feces for carbohydrates is not the main one in making a diagnosis, but it helps to determine the nature of the insufficiency - primary or secondary.
In order to properly collect feces for the determination of carbohydrates in feces, it is necessary to collect it in a clean, dry dish, in a volume of at least 1-2 teaspoons. Feces must be delivered to the laboratory no later than 3-4 hours, otherwise the result will be distorted. Normal values ​​for children under one year old are:
Breastfeeding (before complementary foods) up to 0.5-0.6%,
On artificial feeding - up to 0.3%,
For children from the second half of the year - up to 0.25%,
Older than a year 0%.

With an increase in indicators, a feeding correction is prescribed, the imbalance of milk is eliminated if it is a baby or a low-lactose mixture is temporarily given if it is a baby on IV. If primary lactase deficiency is confirmed, the treatment will consist in the use of the enzyme lactase.

Analysis of feces for opportunistic flora (UPF).
It is this analysis of feces, usually referred to as "dysbacteriosis", that causes the greatest number of questions among parents. However, for the most part, this analysis is uninformative and not indicative. The thing is that the intestinal microflora is very unstable, and even if two analyzes are carried out in a row in the same child in the morning and in the evening, they will differ significantly.

To understand where microbes come from in the intestines, and who should be feared and who should not, let's briefly talk about how the intestines work. Immediately after childbirth, when the baby is applied to the breast, the baby's intestines are populated with microflora from the mother. It becomes like a multi-storey building - there are peaceful neighbors and most of them are bifido- and lactoflora. And there are violent neighbors, but their minority is the so-called conditionally pathogenic flora (staphylococcus aureus, Klebsiella, certain types of Escherichia coli). While all the microbes settle in the intestines, anxiety occurs - physiological dysbacteriosis, until everyone takes their proper places. In addition, the settlement and peaceful existence in the intestines of various potentially dangerous microbes, such as staphylococcus and Klebsiella, is facilitated by help from the mother - breast milk with antibodies to harmful microbes and special substances that help beneficial lactobacilli and bifidoflora grow. That is, all changes in the analysis of feces for microflora in the first 4-6 months of life are a physiological setting for the work and peaceful coexistence of microbes.

What is allowed and what is not?
In this analysis, there are some special indications, so the presence of the causative agent of salmonellosis, cholera, typhoid fever, dysentery and the pathogenic type of Escherichia coli is clearly unacceptable in the feces. But parents, however, are more concerned about the presence of staphylococcus, Proteus, Klebsiella, enterococci in the feces. However, in itself, the presence of any amount of these microbes, in the absence of a clinic for these diseases, that is, if the child does not have a fever, gains weight, grows and develops according to age, is a variant of the norm for this baby. The microflora is called conditionally pathogenic because it can become active and harmful only under certain conditions.

This occurs in children with immunodeficiencies, a sharp decrease in immune forces after severe and prolonged illnesses, after exposure or treatment with heavy drugs - antibiotics for a long course (three or more weeks), antitumor agents. Another reason for the activation of this flora can be intestinal infections and severe poisoning - they simply join the clinic of the disease. In all other cases, correction of the microflora is not required at all - the microbial balance will be restored on its own. The use of any drugs to correct the flora is not required - most of them simply do not reach the intestines, being destroyed by hydrochloric acid of the stomach or intestinal enzymes.

Of course, this is not all of the stool tests that can be performed on a child. However, all other studies are quite specific and are carried out only if significant deviations are found in the general analyzes. They are prescribed by a gastroenterologist and are necessary to clarify the diagnosis, or to monitor the effectiveness of treatment.