Defined in men as 10 to the 5th colony forming units of the same organism isolated on 1 uncontaminated urine sample and in women as 2 samples with the same findings.
In catheterized individuals only 10 to the 2nd colony forming units is required.
These requirements must be met in a patient with no genitourinary symptoms of infection.
In pregnant women screening and antimicrobial treatment for asymptomatic bactiuria reduces rate of pyelonephritis in the mother as well as preterm delivery and low birth weights.
By screening and treating asymptomatic patients undergoing urologic procedures with mucosal disruption the risk of bacteremia is reduced.
Depending on age, sex, and genitourinary abnormalities, the prevalence of asymptomatic bacteriuria has been found to be as low as 1% to 5% in healthy premenopausal women, and approximately 2%-10% in pregnant women, to 100% in patients with long-term indwelling urinary catheters.
The majority of cases of asymptomatic bacteriuria are elderly women and men with a respective prevalence of 11% to 16% and 4% to 19% in the community dwellers.
In adult populations, women have higher rates of asymptomatic bacteria than men, and prevalence increases after menopause for women and old men ( >90).
Prevalence of asymptomatic bacteriuria increasing to 25% to 50% and 15% to 40% in elderly women and men respectively, in long-term care facilities.
Escherichia coli remains the most common bacterial isolate.
Persons with bacteriuria are at an increased risk of symptomatic urinary tract infections, the treatment of asymptomatic bacteriuria does not decrease the frequency of symptomatic infections or improve other outcomes.
The treatment of asymptomatic bacteriuria is associated with a higher prevalence of potentially dangerous antibiotic-resistant strains in women who do go on to have an active urinary tract infection.
Nonpregnant women, elderly men with or without Indwelling urinary catheters receive no benefit from antibiotic treatment of asymptomatic bactiuria, and sometimes experience harm.
While patients with asymptomatic bactiuria experience higher risk of symptomatic UTI, treatment of asymptomatic colonization does not reduce risk of subsequent symptomatic infection.
Asymptomatic bactiuria is not associated with increased kidney impairment, hypertension, urologic malignancy or mortality.
Increased risk of asymptomatic UTI in patients with asymptomatic bacteria is likely due to the factors that support bacterial colonization rather than the current strain of bacteria becoming virulent.
Treating with antibiotics in the above situation only increases the risk of progressive resistant infections without benefits.
Asymptomatic bactiuria frequently associated with less virulent strains of bacteria.
Depending on age, sex, and genitourinary abnormalities, the prevalence of asymptomatic bacteriuria has been found to be as low as 1% to 5% in healthy premenopausal women, and approximately 2%-10% in pregnant women, to 100% in patients with long-term indwelling urinary catheters.
26-68% of patients with asymptomatic bactiuria are inappropriately treated with antimicrobial agents.
Use of antibiotics to treat ASB associated with significant antibiotic overuse in hospitalized and nursing home patients, especially those with urinary catheters.
20-83% of patients with asymptomatic bactiuria are treated unnecessarily with antibiotics.
Evidence is strong against screening for or treating asymptomatic bactiuria in most adults.
Patients with indwelling urinary catheters should not be screened for asymptomatic bactiuria or be treated with antimicrobial therapy.
The use of prophylactic antibiotics before minor urologic events such as cystoscopy and urodynamic studies does not provide any benefit and is not recommended.
It is prudent to screen for and treat asymptomatic bacteriuria before any invasive urologic procedures that may lead to mucosal bleeding, because these have been proven to be associated with a heightened risk of bacteremia and severe systemic infection.
After a procedure, antibiotic therapy is recommended when an indwelling catheter is to be left in place.
The practice of screening for and treating asymptomatic bacteriuria in patients about to undergo orthopedic surgery including total joint arthroplasties is without proven merit.
Rates of surgical wound or site infection are statistically similar in both treated and untreated bacteriuric patients.
During pregnancy, it is present in an estimated 2-10% of women and is associated with an increased risk of symptomatic infection, including pyelonephritis.
Rates of pyelonephritis during pregnancy is low, possibly due to asymptomatic bacteria screening in treatment as a standard prenatal care.