From the Guidelines
Asymptomatic bacteriuria generally does not require treatment in most populations, except for pregnant women and patients undergoing urologic procedures where mucosal bleeding is anticipated. The most recent and highest quality study, 1, recommends that asymptomatic bacteriuria should only be treated in cases of proven benefit for the patient, such as in pregnant women or before urological procedures breaching the mucosa.
Key Points
- Treatment is recommended for pregnant women, with a 3-7 day course of antibiotics such as nitrofurantoin, amoxicillin-clavulanate, or cephalexin.
- Prior to urologic procedures, a single dose of antibiotics based on local resistance patterns should be given.
- Treatment is not recommended for non-pregnant women, elderly individuals, diabetics, or those with indwelling catheters, as studies show no benefit and potential harm from unnecessary antibiotic use.
- The rationale for this approach is that asymptomatic bacteriuria represents colonization rather than infection in most cases, and treating it can lead to antibiotic resistance, medication side effects, and disruption of normal flora without improving outcomes.
Considerations
- Urine cultures should not be routinely ordered in asymptomatic patients except in pregnancy or before relevant urologic procedures.
- Further research is needed to clarify the optimal timing and periodicity of screening for asymptomatic bacteriuria in pregnant women, as well as to develop a screening test that could reduce the use of urine culture. According to 1, the European Association of Urology guidelines recommend screening for and treating asymptomatic bacteriuria before urological procedures breaching the mucosa, and in pregnant women with standard short-course treatment or single-dose fosfomycin trometamol. In addition, 1 and 1 also support the idea that asymptomatic bacteriuria should not be treated in most populations, except for pregnant women and patients undergoing urologic procedures. However, the most recent and highest quality study, 1, takes precedence in guiding clinical practice.
From the Research
Asymptomatic Bacteriuria Treatment
The recommended treatment for asymptomatic bacteriuria varies depending on the patient population and medical condition.
- For pregnant women, a 7-day course of nitrofurantoin is recommended as it has been shown to be more effective than a 1-day course in eradicating asymptomatic bacteriuria 2.
- A study comparing different antibiotic regimens for treating asymptomatic bacteriuria in pregnancy found that there was no significant difference in persistent infection or recurrent infection between the different regimens, but a longer course of nitrofurantoin was more effective 3.
- For other patient populations, such as young women, renal transplant patients, and patients undergoing minor nontraumatic urologic procedures, treatment of asymptomatic bacteriuria is not beneficial and may be harmful 4.
- The treatment of asymptomatic bacteriuria should be based on local patterns of antimicrobial sensitivity and resistance, with nitrofurantoin being the most effective antibiotic in some studies 5.
- Patient populations that should be treated for asymptomatic bacteriuria include neonates, preschool children, pregnant women, and nonelderly men, as well as patients with abnormal urinary tracts or those undergoing certain medical procedures 6.
Antibiotic Regimens
Different antibiotic regimens have been compared in studies, including:
- Fosfomycin trometamol vs cefuroxime: no significant difference in persistent infection or recurrent infection 3
- Pivmecillinam vs ampicillin: no significant difference in persistent infection or recurrent infection, but more vomiting and early treatment cessation with pivmecillinam 3
- Cephalexin vs Miraxid: no significant difference in persistent or recurrent infection 3
- Nitrofurantoin (1-day vs 7-day course): 7-day course more effective in eradicating asymptomatic bacteriuria 2
Patient Populations
Different patient populations have different recommendations for asymptomatic bacteriuria treatment, including:
- Pregnant women: 7-day course of nitrofurantoin recommended 2
- Young women: treatment not beneficial and may be harmful 4
- Renal transplant patients: treatment not beneficial and may be harmful 4
- Patients undergoing minor nontraumatic urologic procedures: treatment not beneficial and may be harmful 4
- Neonates and preschool children: treatment recommended 6
- Nonelderly men: treatment recommended 6