From the Guidelines
Asymptomatic bacteriuria in adults generally does not require treatment except in specific populations, such as pregnant women and patients undergoing urologic procedures with mucosal bleeding, as stated in the most recent guideline by the European Association of Urology 1.
Key Points
- Treatment is recommended only for pregnant women and patients undergoing urologic procedures with mucosal bleeding.
- For pregnant women, a 3-7 day course of antibiotics such as nitrofurantoin 100mg twice daily, amoxicillin-clavulanate 500mg twice daily, or cephalexin 500mg four times daily is appropriate, as suggested by the Infectious Diseases Society of America 1.
- For those undergoing urologic procedures, a single dose of antibiotics just before the procedure is sufficient, typically trimethoprim-sulfamethoxazole or a fluoroquinolone.
- All other adults, including elderly individuals, diabetics, and those with spinal cord injuries or indwelling catheters, should not receive treatment for asymptomatic bacteriuria as it does not reduce complications and may lead to antibiotic resistance, as noted by the U.S. Preventive Services Task Force 1.
Rationale
The rationale for this approach is that bacteria can colonize the urinary tract without causing infection or harm in most individuals, and unnecessary antibiotic treatment disrupts normal flora and promotes resistance without clinical benefit.
Screening
Screening for asymptomatic bacteriuria should only be performed in pregnant women and before urologic procedures, not in other populations, as recommended by the European Association of Urology 1 and the Infectious Diseases Society of America 1.
From the Research
Significance of Asymptomatic Bacteriuria (ASB) in Adults
- ASB is a common clinical condition that often leads to unnecessary antimicrobial use, with the reduction of antibiotic overuse being an important issue for antimicrobial stewardship and to reduce the emergence of multidrug resistant strains 2.
- The incidence of ASB increases with age and is more prominent in women than men, with older women having an incidence of more than 15% and up to 50% for those in long-term care facilities 3.
- In most scenarios, ASB does not lead to urinary tract infections, and therefore, antibiotic treatment of ASB has not been shown to improve patient outcomes 3.
Management of ASB
- The Infectious Disease Society of America (IDSA) updated its ASB management guidelines in 2019, emphasizing the risks and benefits of treating the condition, and recommending screening and treatment for pregnant women and individuals undergoing endoscopic urologic procedures 3.
- Treatment of ASB is not recommended for individuals with diabetes, neutropenia, spinal cord injuries, indwelling urinary catheters, and other conditions, as it has not been found to improve clinical outcomes 3.
- Unnecessary treatment of ASB is often associated with unwanted consequences, including increased antimicrobial resistance, Clostridioides difficile infection, and increased healthcare cost 3.
Screening and Treatment
- Screening for ASB is limited to those undergoing invasive urological procedures and surgical procedures with implant material, and is not recommended in other situations if signs or symptoms in the urinary tract are absent 4.
- Treatment of ASB is recommended only before urological procedures, and pyuria accompanying ASB is not an indication for antimicrobial treatment 4.
- Guidelines are available to help determine which patients may benefit from treatment, and primary care providers should recognize ASB and know when and when not to treat 5.