1 / 20

Asymptomatic bacteriuria

Dr.Esraa AL- Maini. Asymptomatic bacteriuria. Asymptomatic bacteriuria ( ASB ) is defined as persistent bacterial colonisation of the urinary tract without urinary tract symptoms. Asymptomatic bacteriuria ( ASB )during pregnancy. Incidence.

Télécharger la présentation

Asymptomatic bacteriuria

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.


Presentation Transcript

  1. Dr.Esraa AL-Maini Asymptomatic bacteriuria

  2. Asymptomatic bacteriuria (ASB) is defined as persistent bacterial colonisation of the urinary tract without urinary tract symptoms. Asymptomatic bacteriuria (ASB)during pregnancy

  3. Incidence • USA: it occurs in 2–10% , with the higher incidence among women of lower socio-economic status. • UK : it occurs in 2–5% of pregnant women.

  4. Risks during pregnancy • Increased risk of pyelonephritis among pregnant women with ASB ranges from a risk difference of 1.8% to 28% • Increased risk of preterm birth in women who have untreated ASB compared with women who do not have ASB. The risk difference 2.1% to 12.8%.

  5. Diagnosis • Urine culture (midstream) has been used as the reference standard for diagnosis of ASB. • In studies of ASB, a growth of 105 organisms of a single uropathogen per millilitre in a single midstream sample of urine is considered significant(although some tests have used figures such as 104 and 108)

  6. When urine culture is used in screening for ASB. • The drawbacks include the time lag: results are not usually available for at least 24 hours, and the cost. • Its advantages are in being able to identify causative organisms and determine antibiotic sensitivities.

  7. A number of rapid tests have been evaluated against urine culture , These include: • 1-Reagent strip tests • 2-Microscopic urinalysis • 3-Gram stain with or without centrifugation • 4-Urinary interleukin • 5-Rapid enzymatic (detection of catalase activity) • 6-Bioluminescence assay.

  8. Reagent strip tests which test for one or more of the following: • Nitrite, protein ,blood ,leucocyte esterase • Apositive test result is defined as a strip showingany of the following: • More than a trace of protein • More than a trace of blood • Any positive result for nitrite • Any positive result for leucocyte esterase.

  9. This has the advantage of being rapid and inexpensive and requiring little technical expertise The sensitivity of reagent strip testing; • When all tests positive ,orWith either test positive the senstivity 50% At best, reagent strip testing will detect 50% of women with ASB.

  10. Microscopic urinalysis • This test consists of microscopic analysis of urinary sediment and pyuria is deemed significant with ten cells per high-power field • A sensitivity of 25%, which means that 75% of women with ASB will be missed using this test

  11. Gram stain with or without centrifugation • compared with urine culture. A specificity of 7% was reported when urine was centrifuged and considered positive if the same morphotype of bacteria was seen ˃ 6 of 12 high-power fields. In the other study specificity of 89%, urine was not centrifuged and a positive smear was defined as more than two organisms per high-power field. With the low specificity in the more rigorous estimation, more than 90% of women who do not have ASB will be incorrectly identified as cases.

  12. Other tests The urinary interleukin-8 test The rapid enzymatic test (detection of catalase activity) both of which have a sensitivity of 70% and will potentially miss 30% of women with ASB. • A bioluminescence test has been described, with a sensitivity of 93% and a specificity of 78 %.

  13. . There is controversy around whether to use a dipstick or a culture test for screening. • The culture test is relatively more expensive but has a higher sensitivity and specificity. • Regarded as the gold standard, is not cost beneficial when compared with the dipstick strategy, if preterm birth included its cost benifcial .

  14. previous recommendation advising screening for bacteriuria in order to reduce the risk of preterm birth was no longer valid since an update ( no association between treating asymptomatic bacteriuria and reducing the incidence of preterm birth)

  15. Out of pregnancy • Antibiotic treatment of ASB does not reduce frequency of symptomatic UTI • Treatment of ASB in diabetes does not reduce adverse outcomes, improve glucose control, or reduce symptomatic UTIs • It does lead to untreatable drug resistant bacteria • Only exceptions are pregnancy ,patients undergoing urologic procedures (such as prostate biopsy)

  16. During pregnancy • Antibiotic treatment reduced persistent bacteriuria during pregnancy • Reduced risk of preterm delivery or low-birth weight babies • Reduced the risk of development of pyelonephritis by 30%

  17. Treatment: • single-dose antibiotic treatment with a 4 to 7 day course of antibiotic treatment for asymptomatic bacteriuria showed no difference in the prevention of preterm birth pyelonephritis • Longer duration of treatment, however, was associated with increased reports of adverse effects

  18. Follow up: Urin culture should be repeated 1 week after completion of therapy and at regular intervals 15-20%will have recurrent bacteriuria during the same pregnancy Recurrent infection by same organism so renal origin treat by 3 weeks coarse ,but different organism is likely to represent bladder infection and can usually be eradicated with short term therapy. Persistent AB despite 2-3 course of treatment 100mg nitrofurantoin daily usually prevent symptomatic infection

  19. Take home message; • Women should be offered routine screening for asymptomatic bacteriuria by midstream urine culture early in pregnancy(16weeks). Identification and treatment of asymptomatic bacteriuria reduces the risk of pyelonephritis.

  20. Thank you

More Related