Bacteriuria

Bacteriuria is the presence of bacteria in urine. Normally, urine is sterile. Bacteriuria is a symptom of inflammatory diseases of the kidneys and urinary tract. However, not every detection of microorganisms in the centrifuged urine sediment is clinically significant.

The generally accepted indicator reflecting the true nature of bacteriuria is the titer of microbial bodies, which is 10 ⁴ -10 ⁵ CFU in 1 ml of urine. A titer reaching 10 ⁴ CFU/ml is interpreted as bacterial contamination of urine.

It is necessary to keep in mind that these parameters are conditional. Each clinical situation requires their correction. With a decrease in the indices of cellular and humoral immunity, caused by various factors (including immunosuppressive therapy), in conditions of hemodilution of polyuria, a lower level of microbial titer - up to 10 ⁴ CFU/ml - may also indicate the activity of the inflammatory process in the kidneys and urinary tract.

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Causes bacteriuria

If a person's kidneys are healthy and their tissues are not damaged, bacteria will not be able to penetrate from the bloodstream into the urine. Bacteriuria is observed during inflammation in the kidneys, when the renal parenchyma is affected by bacteria, during infection of the bladder, inflammatory process in the prostate gland, it is also provoked by catheterization of the ureters and bladder, insertion of bougies into the urethra, cystoscopy.

The degree of bacteriuria can vary and become severe in the following pathological conditions:

1. Obstruction (closure) of the ureter by a calculus, when a pathological contraction disorder is formed and urine returns to the kidney, already infected with bacteria. Other causes of impaired outflow from the upper zone of the urinary tract are also possible.
2. Prostate adenoma, which becomes a source of inflammation and, accordingly, provokes bacteriuria. Also, a significant narrowing of the urethra (stricture) and urinary retention can increase the degree of bacteriuria.

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Bacteriuria can have both descending and ascending causes.

The descending route of infection in urine is the penetration of bacteria into urine from the inflamed vesica urinaria - urinary bladder, from infected kidney tissue, from the prostate gland, which has hyperplastic glandular tissue. The ascending route of infection of urine is the penetration of microorganisms into urine as a result of unsuccessful catheterization, urological endoscopy - cystoscopy, bougienage, as well as from the large intestine or vulva, if the rules of personal hygiene are not observed (lymphohematogenous route).

Bacteriuria is observed when various types of bacteria enter the urine - these can be streptococci, intestinal and pseudomonas aeruginosa, staphylococci or bacteria from the genus proteus - protei. Any type of bacteria, getting into the genitourinary sphere, causes inflammation of the urinary system or kidneys, but infection with microorganisms is also possible in certain areas of the colon, causing proctitis. Bacteriuria is observed in people who suffer from chronic constipation, hemorrhoids, much less often in patients with brucellosis, typhoid fever, paratyphoid fever and leptospirosis due to the low prevalence of these diseases.

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Pathogenesis

What is bacteriuria?

Bacteriuria is the presence of microorganisms (bacteria) in the urine, which are detected during microscopic examination of urine, usually due to inflammatory disease of the urinary tract, kidneys and genitals in men.

Urine in healthy people should not contain bacteria in principle, in the bacterial sense, urine sterility is an indicator of the health of the kidneys and urinary tract. However, when they are infected, microorganisms enter the urine, bacteriuria develops, leukocyturia and pyuria are possible. Not every contamination of urine can be considered bacteriuria, there are clear boundaries in microscopic identification - exceeding the indicator of 105 per 1 milliliter of urine is a sign of an inflammatory bacteriological process. The longer the urine infected with bacteria is in the bladder, the more pronounced the degree of bacteriuria.

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Symptoms bacteriuria

Bacteriuria demonstrates symptoms in accordance with the underlying disease. Bacteriuria is most often found (diagnosed) in pyelonephritis, urethritis and cystitis.

Bacteriuria can also be a symptom of the following pathologies:

• Prostate adenoma.
• Prostatitis, both chronic and in the acute stage.
• Diabetes mellitus.
• Bacterial sepsis.
• Urethritis.

Bacteriuria exhibits symptoms characteristic of pyelonephritis, urethritis and cystitis, other diseases do not have specific symptoms that allow differentiation of the nosology only by laboratory analysis of urine.

Bacteriuria, symptoms similar to those of pyelonephritis:

• Dysuria – frequent or slow urination, burning, pain.
• Spontaneous release of urine.
• Transient nausea, sudden urge to vomit.
• A sharp increase in body temperature, chills.
• Subfebrile temperature for 1-2 weeks.
• Pain in the lumbar region.
• Pain in the lower abdomen, in the bladder area.
• Cloudy urine, often with pus, with an unpleasant odor that is not typical for urine.

Bacteriuria, symptoms similar to those of urethritis:

• Discharge from the urethra, often with pus.
• Painful urination, dysuria.
• Hyperemic edges of the urethra, irritation, burning.
• Pain in the perineum.
• Elevated body temperature, chills.
• General deterioration of condition, weakness.

Bacteriuria, symptoms identical to those of cystitis:

• Dysuria is frequent, painful urination.
• Burning sensation during urination.
• Frequent urge to urinate with little urine output.
• Uncharacteristic smell of urine.
• Cloudy urine is a change in its color.
• Chronic aching pain in the lower abdomen.
• An increase in body temperature is possible.
• Discharge from the urethra, often with pus.

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Forms

True bacteriuria and false bacteriuria

True bacteriuria is bacteria that not only enter the urinary tract, but also multiply there, causing severe inflammation. False bacteriuria is bacteria that enter the bladder and urinary tract, but do not have time to spread and multiply due to the fact that a person either has an active immune system or is taking antibacterial therapy for an inflammatory disease.

If bacteria accept urine as a nutrient medium, where there are the necessary slightly alkaline and neutral conditions for them, they begin to multiply, sometimes their number exceeds 100,000 in one milliliter of urine. True bacteriuria or significant bacteriuria, as it was called in the middle of the last century by microbiologists Kass and his colleague Finland, is indisputable evidence for diagnosing a urinary tract infection. Despite the fact that signs of inflammation in the bladder can appear earlier with much lower indicators, the Kass and Finland parameter is the only statistically confirmed and is used in laboratory practice today as the main criterion.

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Latent bacteriuria, asymptomatic bacteriuria

Latent bacteriuria is most often detected during routine medical examinations in people who are not bothered by either the bladder, kidneys, or urination problems. Asymptomatic bacteriuria is especially often detected in pregnant women.

In addition to the fact that chronic asymptomatic inflammatory process poses a threat to human health, latent bacteriuria carries a threat of infection and transmission of bacteria to others, provided that the pathogen is a representative of the Enterobacteriaceae family - that is, the typhoid pathogen. The fact that the patient has asymptomatic bacteriuria can be said after a positive two-stage urine test. The material should be collected at intervals of one day, and the bacterial indicator should be confirmed twice within 100,000 per milliliter of urine.

Most often, asymptomatic bacteriuria is detected in women and girls. In men, asymptomatic bacteriuria detected during screening examination is a reason for further diagnostic searches for latent prostatitis. Also, latent bacteriuria is quite often determined in patients over 65 years old, when bacterial colonization is detected chronically, lasting for many years. Most often, asymptomatic bacteriuria occurs in men with prostate hyperplasia and impaired urine outflow, in which bacteria multiply. In most cases, in elderly people, this indicator is not threatening, since the isolated microorganisms are not determined as pathogenic during the study.

Diagnostics bacteriuria

Bacteriuria in urine is determined by collecting fresh urine, usually the middle portion. Urine analysis for bacteriuria is performed after all hygiene procedures are followed to avoid distortion of the results obtained, this is especially important for female patients. The speed of the study is also important, that is, from the moment the material is collected until it is delivered directly to the laboratory, this is necessary to reduce the risk of flora proliferation in warm conditions with access to air. Of course, the "cleanest" in this sense are the samples collected by catheterization or aspiration, but these methods can also provoke bacteriuria, so they are used only in exceptional cases, according to strict indications, for example, when the patient is immobile or the bladder is atonic.

Urine testing for bacteriuria can be performed in several ways.

Bacteriuria in urine is detected either during routine medical examinations or in the case of an already developed inflammatory process. Depending on the purpose and urgency of diagnostics, highly sensitive methods such as urine culture for bacteriuria, which require a lot of time to process the results, or fast but not entirely accurate methods that determine bacteriuria in urine can be used.

As an express method, approximate chemical methods are used:

• TTX test or triphenyltetrazolium chloride reduction method, which uses the property of bacteria to convert the color of colorless tetrazolium salts to blue (a formazan derivative).
• The Griess test is a nitrite method, when nitrates are transformed into nitrites when interacting with bacteria present. Nitrites in turn are detected using special Griess reagents. The test is suitable for the material (urine) of adults, since children's urine usually does not contain nitrates.
• Glucose reduction test, which uses the ability of microorganisms to reduce glucose in small quantities. A reagent (paper strip) is dipped into a morning portion of urine, which shows the presence or absence of glucose. If a certain amount of glucose is absent, this means that it has been “absorbed” by bacteria. The test is not 100% informative, but as an express method it is considered acceptable at the initial diagnostic stage.

Urine culture for bacteriuria

The most informative urine culture for bacteriuria is when the number of multiplying bacteria is counted within certain normal limits. This method is considered the most sensitive, especially for determining the degree of bacterial colonization, but it takes from 24 to 48 hours to perform. Gould's method is shorter and more simplified. Urine culture for bacteriuria according to Gould is a method when the material is sown on agar, in a special Petri dish, in 4 sectors. Each time, urine is transferred to the next sector using a sterile platinum loop. To determine the degree of bacteriuria, only 24 hours are needed, this time is enough for the bacteria to incubate at a comfortable temperature for them - 37 degrees. Then, the number of bacteria is calculated using a special table. Also, a faster culture method is one in which plates covered with a nutrient medium are immersed in urine. After immersion in urine, the plates are quickly moved to special containers, where the bacteria are incubated at a warm temperature for 12-16 hours. The degree of bacteriuria is determined by comparing the results with the normal scale. This is the most accurate test, the reliability of which is within 95%.

Any analysis for bacteriuria should preferably be performed twice, since even with false bacteriuria, the second culture may show a significant increase in the number of bacteria. This is explained by the fact that the first study may have been conducted with material that was collected during heavy drinking or dysuria; distortion is also possible when taking antibiotics or antiseptic drugs. In addition, bacteriuria in urine, with a correctly selected research method, allows you to identify the true pathogen, determine its sensitivity to medications and select adequate treatment.

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Treatment bacteriuria

Any type of bacteria in urine is a signal of possible inflammation in the genitourinary system; therapeutic measures and the choice of drugs depend on the degree of bacteriuria, the patient’s age and physiological condition.

Acute infectious inflammation is treated with the latest generation of antibiotics with a broad spectrum of action and minimal side effects. For the treatment of chronic infections, repeated bacteriuria culture and an antibiogram are required to determine the sensitivity of the pathogen to a certain group of drugs.

Treatment of bacteriuria in pregnant women

Bacteriuria during pregnancy is a fairly common phenomenon, not always associated with inflammation. Often bacteria in the urine appear due to elementary stagnation of urine, also the growing uterus can press on the kidneys and bladder, causing weakness of renal activity and physiological changes in the structure of urine, in addition, the composition of urine is also affected by the hormonal system, which is in an unstable state for all nine months. Therefore, bacteriuria in pregnant women requires repeated examination and confirmation or refutation of the primary results. If the number of microorganisms really exceeds the norm, treatment of bacteriuria in pregnant women is carried out in the most gentle, but at the same time effective way.

The first thing to do is to activate urination (passage) and reduce urine pH with diuretic aseptic drinks, such as cranberry juice. Then, as a rule, cephalosporin drugs are prescribed, less often penicillins, in tablet form for a course not exceeding 3-5 days. This period is considered sufficient in clinical practice for a single attack on bacteria and gentle for the body of the mother and fetus. The first months of pregnancy allow the use of semi-synthetic drugs - amoxicillin, ampicillin, the second trimester allows the use of macrolides. The effectiveness of antibiotic treatment is monitored by repeated cultures for bacteriuria. It is necessary to avoid prescribing the entire group of tetracyclines, fluoroquinolones, antifungal drugs. As a maintenance therapy, the appointment of drugs of the nitrofuran group is indicated, they are usually taken at night.

Asymptomatic bacteriuria during pregnancy is treated with more gentle, rather preventive methods, including herbal medicine, homeopathic remedies such as Canephron, Cyston. Bacteriuria during pregnancy treatment involves the use of very powerful active drugs that are taken once. Such drugs include Monural - an effective uroantiseptic, which is prescribed 2-3 times a day, 3 grams per day. If a massive single dose of the drug does not give results, treatment with cephalosporins is necessary for one week, and possibly for a longer period. It is also important to monitor the timely emptying of the bladder throughout the treatment period and prevent urine stagnation, for this, the pregnant woman's menu should include cranberry and rosehip juice, diuretic infusions.

Asymptomatic bacteriuria during pregnancy is dangerous not in itself, but because it can provoke infection of the urinary tract and create conditions for the development of pyelonephritis. In addition, asymptomatic bacteriuria is a risk factor for the birth of a child with a weight deficit, premature rupture of membranes, anemia, gestosis, placental insufficiency. This is why the treatment of bacteriuria in pregnant women should be as effective as possible in order to prevent possible complications in a timely manner.

In general, treatment of bacteriuria in pregnant women should adhere to the following principles:

• Only those drugs that are guaranteed to be safe and meet bioavailability criteria are prescribed.
• When choosing medications, it is necessary to take into account the trimester of pregnancy, especially the period up to 5 months.
• The entire treatment process must take place under regular and strict medical supervision, including screening tests of blood and urine.

Treatment of bacteriuria in children

Bacteriuria in children, especially in asymptomatic form, does not require independent separate therapy. It is enough to eliminate the main source of infection, and this is actually achieved by antibacterial therapy and activation of the immune system. In addition, the treatment of bacteriuria in children is often associated with the observance of basic hygiene rules, which should be followed by the parents of the sick child. Also, bacteria in the urine often have the opportunity to multiply due to rare urination: the child "forgets" to urinate, getting carried away playing. These points do not seem so important, but according to statistics, about 25-30% of cases of detection of microorganisms in the urine of children are associated with such reasons, which practically do not require treatment. Establishing a diet, monitoring timely urination, eliminating constipation and regularly taking baths, showers - sometimes this is enough for asymptomatic bacteriuria to disappear without a trace. If bacteriuria in children is a consequence of cystitis or pyelonephritis, treatment should be adequate to the underlying disease.

Therapeutic actions to eliminate bacterial infection in cystitis are aimed at improving urination and neutralizing the infectious agent. Of the medications, preference is given to urospasmodics and antispasmodics, antibacterial drugs are prescribed only in cases where a high degree of bacteriuria is confirmed. As drugs that are relatively safe in terms of the presence of side effects, inhibitor-protected penicillins are chosen - amoxicillin, as an alternative, third-generation cephalosporins are chosen. Antifungal agents and macrolides are prescribed only in situations where atypical flora is determined in the urine. Like any other antibacterial therapy, antibiotics are taken for at least 7 days. Of the herbal remedies, it is good to take decoctions of lingonberry leaves, calendula or plantain. In addition, diet therapy, which is an integral part of the treatment of bacteriuria in children, should be long-term and should be followed for at least three months after the end of the course of treatment.