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Evidence summaries

Antibiotics for Asymptomatic Bacteriuria

Antibiotics appear to be of no clinical benefit for asymptomatic bacteriuria in adults compared with placebo or no treatment, but they appear to cause more adverse events. Level of evidence: "B"

Comment: The quality of evidence is downgraded by study limitations (unclear allocation concealment and blinding in half of the sudies).

Summary

A Cochrane review [Abstract] 1 included 9 studies with a total of 1614 subjects. The effectiveness and safety of antibiotics treatment for asymptomatic bacteriuria was assessed in adults of different age, mainly elderly. Treatment varied including nitrofurantoin, trimethoprim, sulpha-trimethoprim, fluoroquinolones, amoxicillin, cefaclor etc. Symptomatic urinary tract infection (UTI) (RR 1.11, 95% CI 0.51 to 2.43; 5 trials, n=1046), complications (RR 0.78, 95% CI 0. 35 to 1.74; 3 trials, n=814), and death (RR 0.99, 95% CI 0.70 to 1.41; 6 trials, n=761) were similar between the antibiotic and placebo or no treatment arms. Antibiotics were more effective for bacteriological cure (RR 2.67, 95% CI 1.85 to 3.85; 9 trials, n=1154) but also more adverse events developed in this group (RR 3.77, 95% CI 1.40 to 10.15; 4 trials, n=921). No decline in the kidney function was observed across the studies; minimal data were available on the emergence of resistant strains after antimicrobial treatment.

A meta-analysis 2 included 50 studies involving 7088 patients. Overall, quality of evidence ranged from very low to low. There was no evidence of benefit for patients with no risk factors, patients with diabetes mellitus, postmenopausal women, elderly institutionalised patients, patients with renal transplants, or patients prior to joint replacement, and treatment was harmful for patients with recurrent urinary tract infection (UTI). Treatment of ABU resulted in a lower risk of postoperative UTI after transurethral resection surgery. In pregnant women, we found evidence that treatment of ABU decreased risk of symptomatic UTI, low birthweight, and preterm delivery.

Clinical comments

Note

Date of latest search:2020-03-07

    References

    • Zalmanovici Trestioreanu A, Lador A, Sauerbrun-Cutler MT et al. Antibiotics for asymptomatic bacteriuria. Cochrane Database Syst Rev 2015;(4):CD009534. [PubMed]
    • Köves B, Cai T, Veeratterapillay R et al. Benefits and Harms of Treatment of Asymptomatic Bacteriuria: A Systematic Review and Meta-analysis by the European Association of Urology Urological Infection Guidelines Panel. Eur Urol 2017;72(6):865-868. [PubMed]

Primary/Secondary Keywords