Bacterial culture of urine with determination of sensitivity to antibiotics
Utolsó ellenőrzés: 07.06.2024
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Urologists quite often encounter in their practice with infectious diseases of the urogenital system. Adequate diagnosis and treatment of such pathologies are impossible without determining the type of pathogen and its resistance to the prescribed antibiotic therapy. To do this, each patient must pass a bacterial culture of urine with determination of sensitivity to antibiotics. This is a mandatory study in many urogenital disorders.
What does a urine culture mean and show?
Bacterial culture of urine with determination of sensitivity to antibiotics is one of the frequently prescribed and quite accurate diagnostic tests of urinary fluid composition. As a rule, such diagnostics is appropriate to clarify the diagnosis, to follow the dynamics of treatment, to assess the general condition of the body of children and pregnant women.
Bacterial culture is prescribed to determine the presence of bacteria in the urine, their identification and assessment of resistance to antibacterial drugs, as well as to confirm or refute the diagnosis of infectious-inflammatory processes.
While performing a urine culture, laboratorians calculate the concentration of infectious agents present and therefore assess the condition of the urogenital system and associated organs.
Bacterial culture of urine is considered a very accurate and informative analysis. Thanks to it, it is possible to determine the number and type of pathological pathogen. And after determining the sensitivity to antibiotics, the doctor has the opportunity to prescribe the correct and effective treatment. [1]
Thus, bacterial seeding of urine helps:
- to identify the causative agent of the infectious process;
- find out his concentration in the urine;
- Determine which antibiotics will be effective in controlling the pathogen and which will be useless or ineffective;
- to track the progress of the treatment.
Az eljárás indikációi Bacterial culture of the urine
Bacterial culture of urine with determination of antibiotic sensitivity is an important test for many diseases and conditions. Sometimes it is prescribed as part of screening to prevent infectious and inflammatory pathologies of the genitourinary sphere in persons at risk:
- pregnant women;
- old people, bedridden patients;
- patients with diabetes mellitus or oncologic pathologies.
The main indication for this test is suspected infectious lesions of the genitourinary system. Although in many cases, in the presence of symptoms of infection, doctors empirically prescribe an antibacterial drug, usually with a broad spectrum of activity. Such a scheme "works" in about 78% of cases. But in some cases, a bacterial culture of urine with determination of sensitivity to antibiotics is considered mandatory:
- If an infectious process is suspected in a woman during pregnancy;
- if pyelonephritis is suspected;
- if the infectious process is found in men;
- if there is an outbreak of an in-hospital urologic infection;
- If the patient was used prolonged catheterization, cystoscopy, after which the patient has a fever;
- If there are high fever readings in children under 3 years of age with no apparent cause;
- if there is a regular exacerbation of genitourinary infectious pathology, or the prescribed empirical treatment is ineffective;
- if it is a complicated inflammatory urinary process, especially in elderly patients;
- if urinary pathology develops in patients with impaired immune status, chronic renal pathologies, congenital defects of the kidneys or urinary system, or in patients operated on for renal transplantation.
There are a number of recommendations, according to which a bacterial culture of urine with the determination of sensitivity to antibiotics is prescribed, even if there are no pathological symptoms:
- pregnant women from the term of 14 weeks, to prevent the development of pyelonephritis;
- patients prior to urogenital surgery;
- patients during the first 8-10 weeks after renal transplantation or in case of any abnormalities of the transplanted organ.
A urine culture for cystitis
Cystitis is an inflammatory process in the mucosa of the bladder, a hollow organ in which urinary fluid accumulates. Urine flows continuously from the kidneys into the bladder and then leaves the body through the urethra.
Cystitis can be acute and chronic, infectious, traumatic, chemical, primary or secondary. To diagnose the disease, a general examination of urinary fluid with microscopy of the sediment, as well as bacterial culture of urine with determination of sensitivity to antibiotics (often - for a wide infectious spectrum) are performed as standard.
The bacterial assay is performed using nutrient dense media. Bacterial identification is performed using mass spectrometry and a special analyzer. Antibiotic sensitivity is determined by disk-diffusion method using a special analyzer.
Antibiotics are specific medications with undoubted antibacterial efficacy. However, most microorganisms are able to develop resistance to these drugs. Such a process can be observed especially often when prescribing antibiotics without a valid indication, with several courses of antibiotic therapy in a row, with regular self-medication and prophylactic use of such drugs. Therefore, before prescribing one or another antibacterial drug for cystitis, the doctor should perform a bacterial culture of urine and determine which antibiotic will be most effective and appropriate.
In patients with cystitis, the most frequent bacterial examination reveals Enterobacteriaceae, pseudomonads, staphylococci and streptococci, enterococci, yeast-like fungi.
Urine culture for pyelonephritis.
Pyelonephritis is an infectious and inflammatory renal pathology, which is most often found in young children, pregnant women, elderly men suffering from inflammation or adenoma of the prostate gland.
Pyelonephritis can be provoked by a bacterial infection existing in the body or entering the kidneys from the environment. Weakened immunity, chronic inflammatory processes, hypothermia, endocrine and liver diseases contribute to the development of the disease. Also, the risk of pyelonephritis increases if the patient's urinary outflow is disturbed - for example, with urolithiasis, prostate adenoma, etc., as well as diabetes mellitus, neurogenic urinary dysfunction.
It is very important to diagnose pyelonephritis as early as possible. To do this, it is necessary to perform a general blood test and biochemical analysis, a general urinalysis, bacteriological seeding of urine with determination of sensitivity to antibiotics, as well as ultrasound of the pelvic organs. Such studies are recommended not only at the beginning of the disease, but also in the process of treatment. Control bacteriochemistry of urine in the absence of complications of pyelonephritis is performed on the fourth day of antibiotic therapy 10 days after its completion. If pyelonephritis runs with complications, then the bacterial examination is performed a week after the start of antibiotic treatment, as well as a month after the completion of the therapeutic course.
Urine culture for glomerulonephritis
Glomerulonephritis is a group of diseases characterized by damage to the glomeruli (renal tubules) in both kidneys. Pathology is accompanied by renal dysfunction, namely, the inability to eliminate metabolic products, toxic substances and excess fluid from the body. If the disease is not detected and treated in time, it is soon complicated by nephrosclerosis (sclerosis of the renal tubules), renal failure - up to the situation in which the patient requires urgent transplantation of the organ.
Therapy for glomerulonephritis is prolonged, complex. Diagnosis is based on the study of blood and urine. The analysis of urinary fluid is characterized by proteinuria, cylindruria. Bacterial seeding of urine with determination of sensitivity to antibiotics is an auxiliary type of diagnosis, to exclude the bacterial cause of the development of the disease. A common root cause of the development of chronic glomerulonephritis is beta-hemolytic streptococcus group A (a common causative agent of chronic tonsillitis and sore throat). This bacterium activates the development of inflammation in the glomeruli and triggers the production of autoantibodies targeting the body's own cells. Regular recurrences of the disease entail the replacement of renal parenchyma with connective tissue and the development of nephrosclerosis, with further transformation of the pathology into chronic renal failure.
Készítmény
Preparation for the collection of urine for bacteriologic analysis takes into account the following steps:
- The day before the test, the patient should refrain from excessive physical exertion and alcohol consumption;
- a day before the collection of biomaterial should avoid the consumption of foods and drugs that can change the color of the urinary fluid (beets, multivitamins, carrot juice, etc.);
- one day before the collection of biomaterial should not take diuretics, one month before the collection - stop taking chemopreparations (in consultation with a doctor);
- immediately before collecting urine, the external genitalia should be thoroughly washed to avoid the introduction of bacteria into the biomaterial;
- If possible, women should avoid taking a bacterial culture test during menstrual bleeding;
- collected material should be brought to the laboratory within 1 hour.
What is the correct way to take a urine culture test?
To submit urine for bacterial culture with antibiotic sensitivity testing, a morning urine sample is collected immediately after waking up (and after hygienic procedures). If it is not possible to collect material immediately, urine fluid is collected 2-3 hours after the last episode of urination.
Immediately before collection, the external genitalia and hands should be washed well - always with soap and water. No antiseptic or disinfectant solutions should be used, as they can distort the diagnostic results.
The jar or container must be sterile, with a tightly screwed lid: it is best to purchase such a container directly from the laboratory or pharmacy. Do not allow foreign liquids or secretions to enter the container, do not dip fingers, objects, etc. Into it. The lid of the jar should be opened immediately before urine collection and closed immediately after collection to avoid bacteria from the external environment.
Urinary fluid collected for bacterial culture and antibiotic sensitivity should be brought to the laboratory as soon as possible: within 1-2 hours. It is highly undesirable to leave the biomaterial in rooms with temperatures exceeding +20°C. The optimal temperature for short-term storage of the material is +8 to +15°C. It is forbidden to freeze urine before bacteriological examination.
Prolonged or improper storage of urine for bacterial seeding can lead to changes in the physiologic properties of the fluid, growth of microbial flora, and damage to the sediment. [2]
Urine culture jar
Special jars are available in pharmacies and laboratories for the subsequent vacuum collection of a sterile urine sample. Modern containers have several advantages. First of all - it is convenience in the collection of material for research: urine can be collected both in a special room in the laboratory, and at home. The patient does not need to look for a more or less suitable container, sterilize it, label it, etc. In addition, biomaterial in a quality sterile container is preserved longer: the tightness of the container completely excludes the loss of sterility and the possibility of leakage of liquid on the way to the laboratory.
What should I not eat before a urine culture?
On the eve of collecting urine for bacterial culture, it is undesirable to consume foods that can change the color of the biomaterial. For example, it is desirable to temporarily refuse to eat:
- beets and dishes based on this root vegetable;
- carrots;
- blueberries, blackberries;
- cherries;
- rhubarb, sorrel;
- beans;
- beer, wine and beverages containing coloring ingredients.
Some prepared foods sold in stores also contain food coloring. Their presence must necessarily be indicated among the ingredients on the package. Such dyes can not only color the urine, but also additionally burden the kidneys, irritate the walls of the urinary ducts and bladder.
Technika Bacterial culture of the urine
Bacteriological (bacterial) seeding of urine involves detection and identification of microorganisms that are in the biological fluid, as well as determining their concentration content. For this purpose, urine is applied to a medium favorable for the growth and development of bacteria (the so-called "nutrient medium"): most often agar or sugar broth is used. [3]
In the absence of subsequent growth of microorganisms, a negative bacterial examination is said to be negative. If growth is present, and the concentration of pathogenic flora is sufficient for the development of the infectious process, the result of the study is considered positive.
Concentration content is the number of microorganisms per unit volume of biological material. It is expressed in CFU - colony forming units. Such a unit is one cell or cell group capable of producing a visible bacterial colony.
If the result of the bacterial culture is positive, the next step is to determine the sensitivity of the identified microorganism to antibiotics (antibioticogram). The study allows you to determine which antibiotics will have no effect on the bacteria, which will have a weak effect, and which will be maximally effective. [4]
Midstream urine culture
Why is it recommended to collect the middle portion of urine for bacteriologic (bacterial) culture? We are talking about morning urine, taken from the middle of urination, it is called the "middle portion". That is, urination is started in the toilet, after one or two seconds put a container for collecting urine, collect at least 20 ml (better - 50 ml). The remaining urinary fluid is again directed into the toilet bowl. Such an approach allows to consider the studied parameters more objective.
Daily urine culture
A daily urine test, which evaluates the urine excreted by the patient over a 24-hour period, is used to check the functional status of the kidneys and to assess the excretion of certain substances with the urinary fluid over a 24-hour period. The urine is collected in a large sterile container with measuring divisions (to determine the total volume of the collected material).
The first "morning" portion is released into the toilet, and the subsequent urine is collected overnight in one large container, which is stored in the refrigerator.
Upon completion of collection, the volume obtained is estimated and the urine sample is transported to the laboratory.
As a rule, a daily analysis is prescribed to determine the total volume of urine, creatinine, urea, protein, glucose, oxalates. The need to perform a bacterial culture is discussed with the doctor on an individual basis.
Urine culture in women
For bacterial culture and antibiotic sensitivity testing, women should collect morning urine from the first urination after waking up. If a woman goes to the toilet several times during the night, the urinary fluid that can be collected 1-2 hours before delivery to the laboratory should be collected for testing.
It is very important to wash the genitals thoroughly and to make sure that no vaginal secretions get into the urine. It is recommended to temporarily insert an intravaginal tampon after the hygienic procedure to prevent vaginal secretion from entering the urine sample. It is desirable to collect a medium portion of fluid without interrupting the urinary process.
Collecting material for bacterial culture during active menstrual discharge is not recommended. It is usually done before or a few days after menstruation.
Urine culture for men
To perform a bacterial urine culture, men collect a mid-morning urine sample from the first urination after waking up. Important: deliver the material to the laboratory as soon as possible. It is optimal to do this within an hour.
Before collecting urinary fluid, you should take a shower and wash your genitals thoroughly. The head of the penis and the foreskin should be washed with soap and warm water, then dried with a towel. During urination and collection of biomaterial, the head of the penis should be in an open state. Such simple rules will help to avoid errors in the result of bacteriological examination.
If a man is found to have bacteriuria without certain symptoms, then he is prescribed additional examination, to exclude pathologies on the part of the prostate gland.
A urine culture on a baby
Bacterial culture is often prescribed for children of different ages. And, if older children can quite explain all the stages of urine collection and perform them, then taking biomaterial from small children sometimes causes difficulties.
In order to collect the right amount of urine from babies, pharmacies sell special children's urinalyses - 100 ml containers with a special attachment with an adhesive hypoallergenic base. There are different types of urinal pouches - first of all, depending on the sex of the child. The kit comes with instructions on how to use the container, which contain the following recommendations:
- the baby should be thoroughly washed, dry the skin with a soft towel;
- After releasing the urinal from the packaging, remove the protective film from the adhesive part;
- The child is placed on his/her back, legs spread, and the container is turned posteriorly with the anteroposterior notch toward the back to prevent accidental feces from entering the main container;
- if the procedure is performed on a boy, his genitals are lowered into the special opening of the container;
- the adhesive surface is pressed down slightly;
- If the procedure is carried out on a girl, the urinal is glued between the anus and the labia majora and then to the perineal skin;
- after fixation, the child is put on panties or diaper, taken upright in the arms, waiting for the urinary act;
- after urine collection, the urine collector is peeled off, drained from the reservoir into a sterile transport container and sent to the laboratory.
Normál teljesítmény
Bacteriologic seeding of urine involves the following steps:
- biological material is sown on nutrient media;
- are raised in an incubator;
- the grown microorganisms are placed in a Petri dish and grown again;
- bacterial colonies are separated from each other and placed back into the incubator conditions;
- the obtained material is subjected to examination, microorganisms are identified, and tested for sensitivity to antibiotics (which antibacterial drugs will kill these microorganisms).
A normal urine bacterial culture determines the absence of microbial growth in the biomaterial. The results form is labeled "no growth". [5]
Az értékek emelése és csökkentése
The following interpretation of the results obtained in a bacterial urine culture is commonly used:
- Normal: no growth of bacterial flora.
- Contamination with associated microorganisms allowed the isolation of low titers of one or more bacterial species.
- The titer of microorganisms is more than 10*4 CFU/mL, monoculture is predominantly determined.
- The chronic inflammatory process is characterized by mixed bacterial growth.
Bacterial seeding of urine is evaluated both qualitatively (by the fact of the presence of the pathogen in the biomaterial) and quantitatively (by the concentration of detected microorganisms).
The quantitative indicator is deciphered as follows. There are four degrees of growth, or contamination, in the laboratory:
- at the first degree speak about the growth of single colonies (up to a dozen);
- in the second degree speak of scant bacterial growth, 10 to 25 colonies;
- in the third degree, multiple colonies are found, but they are countable (at least 50);
- in the fourth degree there is a continuous growth of colonies, which cannot be counted.
The colonial count totals in CFU/mL are interpreted as follows:
- If the indicator does not exceed 10³ microorganisms per 1 ml of urine, it indicates the absence of an inflammatory process and is often a consequence of contamination of the biomaterial.
- If the indicator is104 bacteria in 1 ml of biomaterial, then they say that the result is doubtful. It is recommended to repeat the bacterial culture.
- If the indicator is105 bacteria per 1 ml of biomaterial and higher, it indicates the presence of an inflammatory disease.
Bacterial seeding of urine 10 in the 3rd, 4th, 5th, 6th, 7th degree can already indicate the etiology (cause) of the inflammatory process. At the same time, the first and second degree of presence of opportunistic microorganisms often only indicates contamination of biomaterial or improper collection of urine.
When exclusively pathogenic flora is detected, all colonies detected are counted, regardless of degree. [6]
Escherichia coli
Escherichia coli in a urine culture is most often found in cystitis: the bacterium is a representative of the normal intestinal microflora, but virulent types of this microorganism can enter the bladder through the urethra and cause the development of an inflammatory process.
In cystitis, the doctor prescribes a general urinalysis as standard. Bacterial culture with determination of sensitivity to antibiotics is carried out additionally, to accurately determine the presence and type of bacteria, and to assess the most effective antibacterial drug. If a large number of E. Coli are found, patients are necessarily prescribed a more detailed examination, including ultrasound of the urogenital system and cystoscopy.
Enterococcus faecalis
Enterococcus agar (Serva or Difco) or Oxoid is used for the isolation of enterococci. Many media contain triphenyltetrazolium chloride, which is broken down by enterococci and stains them pinkish crimson. Oxoid medium contains bile salts, to which enterococci are resistant, as well as esculin and ferric citrate.
Enterococcus faecalis, or faecalis, is a type of enterococci, which is part of the normal intestinal flora. However, pathogenic forms of bacteria can cause the development of infectious inflammatory processes in the urinary tract, pelvic organs. On true bacteriuria (infectious process) is said if during the bacterial culture is found at least105 microbial bodies per 1 ml of urinary fluid. If the concentration of microorganisms is lower, it is assumed that bacteria got into the urine during the improper collection of material for analysis (provided that there are no symptoms of infectious disease).
Statistically, fecal Enterococcus faecalis is found in 1-18% of cases of positive bacterial examination. The other types of enterococcal flora are detected much less frequently.
Citrobacter coseri
Citrobacter is a Gram-negative, spore-forming, facultative-anaerobic bacterium that is normally a member of the opportunistic intestinal flora in humans.
Citrobacter belongs to the family Enterobacteriaceae and the type of Proteobacteriaceae. Besides Citrobacter coseri, there are also Citrobacter freundi, Amalonaticus, Bitternis, Europeus and many other bacteria. This microorganism most often becomes the causative agent of in-hospital angiogenic infections and infectious lesions of the urinary system, can provoke outbreaks of toxicoinfections, gastroenteritis, meningitis, purulent infections.
Citrobacteriosis is diagnosed only after bacterial culture or other specialized laboratory tests.
Klebsiella pneumoniae in urine culture
Klebsiella pneumoniae belongs to Gram-negative facultative-anaerobic opportunistic pathogenic bacteria, normally present in the intestine, oral cavity, on the human skin. This microorganism does not form spores, is immobile, capable of forming capsules.
The number of Klebsiella pneumoniae can increase rapidly during the development of infection, as well as after a long course of antibiotic therapy, when there is suppression not only of pathogenic flora, but also of normal intestinal flora (Klebsiella, staphylococci, enterococci, etc.). For the urinary system, Klebsiella is always a pathogenic bacterium and often results from an in-hospital infection.
Urine culture for fungus
Sabouraud's medium with chloramphenicol (400 mg/l) is used for sowing yeast-like fungi. Incubation of sowing takes place for 1-2 days under certain temperature conditions.
A urine culture of a healthy person should not reveal fungi. But sometimes they are still detected: so, candida, mold and ray fungus often appear in the analysis. This is possible with primary or secondary immunodeficiency, improper antibiotic therapy, infectious processes in the urogenital system.
The most common and frequently identified fungal infection is Candida. In women, these fungi often reside inside the vagina and can pass through the urethra into the bladder. In many cases of thrush, candiduria is due to improper collection of urine for examination.
If the presence of fungi in the urinary fluid is not accompanied by any symptoms, then the doctor may not prescribe treatment. However, such treatment is necessary if the patient suffers from diabetes mellitus, immunodeficiency conditions, genitourinary tuberculosis, if the patient has impaired urine flow or a urinary catheter.
Urine culture for bacteriophages
Bacteriophages are viruses that "eat" bacteria. They are natural non-cellular agents capable of entering the bacterial cell and attacking it from the inside.
According to the type of interaction with bacteria, virulent and moderate bacteriophages are distinguished. The bacteriophage enters the cell with the help of enzymes. The bacteriophage leaves the cell due to its lysis.
Determination of the sensitivity of microorganisms to bacteriophages is necessary if their use as part of complex therapy is assumed.
Urine culture for Mycobacterium tuberculosis
Tuberculosis is a common pathology that occurs in both humans and animals. The causative agents of the disease are aerobic bacteria of the genus Mycobacterium, living in water and soil. Tuberculosis is most often caused by Mycobacterium tuberculosis, less often by Mycobacterium bovis. Both microorganisms are very resistant in the external environment, can cause the development of the disease even several years after infection. It is important that tuberculosis mycobacteria are able to form specific L-forms, which provide anti-tuberculosis immunity.
Many techniques for laboratory diagnosis of the disease are known. These are smear microscopy using sputum, immunoenzymatic analysis, classical culture method. When sowing urine on a nutrient medium, the grown colonies are used to determine sensitivity to antibiotics.
Normally, there should be no mycobacteria in the urine. Their presence is considered as a positive result of tuberculosis diagnosis.
Urine culture for ureaplasma
Ureaplasmosis is an infection that is caused by such a pathogen as ureaplasma. These microorganisms parasitize in the urogenital system, respiratory tract of a person. Microbiological properties and structure of ureaplasma has much in common with mycoplasma. These are conditionally pathogenic bacteria, normally present and in healthy people. Large concentrations of ureaplasma can provoke the development of various pathologies, from cystitis to pneumonia.
Culture diagnostics in the form of bacterial culture of urine additionally allows to determine the sensitivity of the microbe to antibiotics. In addition to bacterial culture, microscopic and serologic methods, molecular biological examination of urine, prostate secretions, semen, etc. Can be used.
Urine culture for staphylococcus aureus.
Staphylococcus aureus is a group of bacteria widespread in nature, combining along with saprophytic and pathogenic forms of microorganisms with varying degrees of pathogenicity and virulence.
For the isolation of staphylococci, yolk-salt agar, milk-salt agar or a special commercial medium (staphylococcal agar) are used.
Bacterial seeding of urine is prescribed when infectious lesions are suspected: the study determines the causative agent and its quantity with great accuracy. Among the staphylococci in the urine most often detected staphylococcus epidermidis and aures - Staphylococcus aureus. The latter belongs to the Gram-positive coccal flora, it has a wide distribution and is often detected even in healthy people (about every fourth person). Staphylococcus aureus is capable of causing the development of infectious diseases such as sepsis, peritonitis, purulent dermatologic pathologies, genitourinary infections, pneumonia.
The presence of Staphylococcus epidermidis in a urine culture may require sensitivity determination to antibiotics such as Vancomycin, macrolides, beta-lactams, aminoglycosides, fluoroquinolones. However, treatment is not always prescribed:
- If the concentration of staphylococcus in the urine is less than 1000 CFU per ml, it indicates the absence of an infectious-inflammatory focus in the body;
- If the indicator is 1000-100000 CFU per ml, a repeat bacterial culture is prescribed;
- If the indicator is more than 100000 CFU per ml, then treatment is prescribed necessarily.
Urine culture for streptococcus.
Streptococci are sown on Columbia agar medium supplemented with defibrinated blood, nalidixic acid and colistin. In addition to streptococci, coagulase-positive staphylococci are isolated on this medium.
Only viridans streptococci are recognized as friendly to the urogenital system. Therefore, their presence in the urine can be considered normal. The predominant number of infectious lesions develop when affected by group A streptococcus. In humans, the pathogen can cause glomerulonephritis, vasculitis, rusty inflammation, impetigo and so on. Group B streptococcus most often affects the genitourinary tract: in men, the bacterium is found in the urethra, and in women - inside the vagina.
Streptococci cause mostly uncomplicated infections, less often - complicated (when affected by group B streptococci).
Urine culture for opportunistic flora
Most bacteria, microorganisms, fungi and protozoa belong to the category of conditionally pathogenic. That is, they are part of the normal biocenosis - the microflora of the vagina and intestines. However, they are non-pathogenic only if their number does not exceed certain limits. If such opportunistic microorganisms become unacceptably numerous, an infectious process develops.
The opportunistic flora includes Enterobacteriaceae, non-fermenting gram-negative microorganisms, staphylococci, enterococci, fungi. An adequate amount of such flora does not require treatment, it is not necessary to completely get rid of it.
Urine culture for asymptomatic bacteriuria
Asymptomatic bacteriuria is a condition in which the abnormal presence of bacteria in the urine is detected, but there are no external symptoms.
Asymptomatic bacteriuria is in many cases inappropriate to treat because it rarely causes complications. In addition, such therapy can be difficult. Prescribed antibiotic therapy can further upset the bacterial balance in the body, which can lead to microbial overgrowth, which will be increasingly difficult to treat.
Treatment can only be prescribed in such cases of asymptomatic bacteriuria:
- when you're pregnant;
- after a kidney transplant;
- for immunodeficiency conditions;
- for urinary reflux;
- before transurethral resection of the prostate.
The decision to treat is made by the attending physician.
How many days is a urine culture done?
Bacterial culture of urine is a highly informative test. However, it has a certain disadvantage: it takes a long time to wait for the result. Bacterial seeding is carried out in stages, each stage takes several hours. In general, the study can last 5-7 days, sometimes up to ten days.
Treatment
Therapeutic measures after a bacterial urine culture are not always appropriate. For example, in asymptomatic bacteriuria there is no need for antibiotic therapy.
Normally, urinary fluid is sterile and free of microorganisms. However, under certain conditions, bacteria can multiply in it - for example, this often happens in diabetics and sexually active women.
In males, asymptomatic bacteriuria is not often observed. However, even here, treatment is not prescribed until the patient is fully examined and diagnosed - for example, the cause in men is often bacterial prostatitis.
Why is the presence of bacteria in a urine culture without clinical symptoms not a reason to prescribe antibiotics?
Asymptomatic bacteriuria usually does not cause complications and does not affect the development of renal and genitourinary pathologies.
Antibiotics almost immediately eliminate bacteriuria, but after a few months the problem reappears: thus, antibiotic therapy without eliminating the cause of bacteria in the urine becomes not only useless, but also harmful, as it threatens the development of resistance of microorganisms.
Culturing bacteria in the absence of symptoms requires treatment:
- when it comes to a pregnant woman;
- if the patient has had a kidney transplant;
- If the patient is going to undergo genitourinary surgery (e.g. Transurethral adenomectomy).
In such situations, short courses of antibiotic therapy are indicated - for example, fosfomycin (Monural), penicillin or cephalosporin antibiotics (Suprax, Amoxiclav) may be prescribed.
In all cases, when a patient undergoes a bacterial culture of urine with the determination of sensitivity to antibiotics, it is assumed that the drug to which there is the greatest susceptibility of the detected microorganisms is used.