Urine bacteriogram in pregnancy

In addition to the fact that pregnant women in the early stages should be examined (including taking all the necessary tests), laboratory testing of urine for the presence of bacteria in it (to determine their type and number) - bacteriologic or bacteriologic urine test in pregnancy - is among the tests that allow timely detection of problems with the bladder and urinary tract, often occurring in women during pregnancy.

Indications for the procedure of the urine bacteriopsy in pregnancy

It should be borne in mind that during pregnancy - due to hormonal and physiological changes - the urethra shortens (by about 3 cm); the urethra dilates; under the pressure of the growing uterus, the bladder volume decreases; there may be stagnation of urine (due to compression of the urethra), leading to bladder-ureteric reflux. The body's ability to resist infection is also reduced due to temporary physiologic immunosuppression. All of these combine to increase the likelihood of developing urinary tract infections.

Why do I need a urine culture during pregnancy? To detect germs in the urine that can cause infection of the urinary tract - bladder, ureters, urethra and kidneys.

First of all, indications for this laboratory test include the presence of symptoms cystitis in pregnancy (frequent urges to urinate, burning when urinating, etc.). See also - Cystitis in early pregnancy

The most significant factor predisposing to urinary tract infections in women during pregnancy, experts consider asymptomatic bacteriuria, affecting up to 6-10% of pregnant women. This is when there is bacterial colonization of the urinary tract, but the microorganisms do not manifest themselves for a long time.

If asymptomatic bacteriuria is not treated, the risk of activation of uropathogenic microorganisms with the development of urinary tract infections increases manifold, and, according to WHO, with asymptomatic bacteriuria in 45% of pregnant women develop pyelonephritis.

In addition, bacteriuria during pregnancy is associated with the risk of preterm labor and delivery of an underweight infant. [1]

Preparation

On how to take a urine culture in pregnancy, as well as how to collect a urine culture in pregnancy, read in detail in the publication - Bacteriostasis testing in pregnancy

Technique of the urine bacteriopsy in pregnancy

In the case of a urine bacteriological test in pregnant women, the technique of performing the test - by sowing the biological material (i.e. Urine) into a nutrient medium and keeping it at body temperature for a day (so that the bacteria can be identified by electron microscopy or mass spectrometry) - in any certified medical laboratory is similar to the technique of performing a urine sterility test. [2] And read more about it in the articles:

• Sterility test: how to pass, what it shows
• Bacterioscopic examination of urine sediment

What does a urine culture show in pregnancy?

The doctor's interpretation of the results obtained in the bacteriological examination of urine provides objective data regarding the degree of infection of the urinary tract and specific infectious agents.

A colony forming unit, CFU/mL, is used to count the number of bacteria present in one milliliter of urine sample.

Until recently, urine was considered a sterile biological fluid, but after the American Society for Microbiology conference in May 2021, this postulate was challenged.

If the threshold value of 10-50 CFU/mL is not exceeded, these are normal urine bacteriuria values. In the case of asymptomatic bacteriuria, a positive urine sample is determined at 100 CFU/mL, and at ≥105 CFU/mL, bacteriuria is considered significant. A similar level is also an indicator of urinary tract infection.

Thus, the presence of pathogenic bacteria in the urine at the level of 100 CFU/mL is considered significant, and this is a positive culture, that is, a poor urine culture in pregnancy, requiring the prescription of adequate treatment with mandatory bacterial examination after its completion. [3]

Urine culture for Escherichia coli in pregnancy (performed with a general culture of urine) is important for prescribing the correct treatment of infection and inflammation in the urinary tract, because it is more often caused by Escherichia coli.

Enterobacteriaceae Escherichia coli also colonize the urinary tract in asymptomatic bacteriuria. In addition, Enterococcus faecalis may be detected in a urine culture in pregnancy; group B streptococci (Streptococcus agalactiae); pseudomonads (Pseudomonas aeruginosa), Proteus mirabilis and Klebsiella pneumonia; staphylococci (Staphylococcus saprophytics, Staphylococcus epidermidis).

Streptococcus in a urine culture in pregnancy is detected much less frequently than Escherichia coli. In most cases, it is a serogroup B Streptococcus agalactiae, the prevalence of which is estimated at about 50% among women as an asymptomatic carrier (as part of the normal microbiota of the gastrointestinal and genitourinary tracts).

In pregnancy, these bacteria can be spread either intrauterine (ascending) or during labor by neonatal aspiration of infected amniotic fluid (with the risk of the newborn developing pneumonia, meningitis, or sepsis).

In addition, carrying streptococcal infection can lead to the development of chronic glomerulonephritis in pregnancy, which in turn causes maternal renal failure, delayed prenatal fetal development, and premature labor.

Bacteriologic testing, as with other microorganisms, includes urine culture for Staphylococcus aureus in pregnancy. In particular, the detection of Staphylococcus saprophytics can be both in acute cystitis and in cases of asymptomatic bacteriuria. But Staphylococcus aureus is very rarely the cause of urinary tract infection, and its isolation in a urine sample is usually secondary to staphylococcal bacteremia. [4]

Also useful information in the materials:

• Bacteria in urine: what does it mean?
• Bacteria in urine in pregnancy
• Types and what are the dangers of bacteria in urine?