Medicine Central™ is a quick-consult mobile and web resource that includes diagnosis, treatment, medications, and follow-up information on over 700 diseases and disorders, providing fast answers—anytime, anywhere. Explore these free sample topics:
-- The first section of this topic is shown below --
Asymptomatic bacteriuria (ASB) is diagnosed when significant bacteriuria is not accompanied by signs and symptoms attributable to urinary tract infection (UTI).
- General population: 3.5%
- Pregnancy: 7–10%
- Older women: 16–18%
- Variable, increased with age, female gender, sexual activity, and presence of genitourinary (GU) abnormalities
- Pregnancy: 2–10%
- Short- and long-term indwelling catheter 9–23% and 100%, respectively
- Long-term care residents in women 25–50% and men 15–40%
Etiology and Pathophysiology
- Microbiology is similar to that of other UTI, with bacteria originating from periurethral area, vagina, or gut.
- Organisms are less virulent in ASB than those causing UTI.
- The most common organism is Escherichia coli. Other common organisms are Klebsiella pneumonia, Enterobacter, Proteus mirabilis, Staphylococcus aureus, group B Streptococcus (GBS), and Enterococcus.
Genetic variations that reduce toll-like receptor-4 function (TLR4) have been associated with ASB by lowering innate immune response and delaying bacterial clearance.
- Older age
- Female gender
- Sexual activity, use of diaphragm with spermicide
- GU abnormalities: neurogenic bladder, urinary retention, urinary catheter use (indwelling, intermittent, or condom catheter)
- Institutionalized residents
- Diabetes mellitus
- Immunocompromised status
- Spinal cord injuries or functional impairment
- Pregnancy (decreased peristalsis of the urinary tract)
Commonly Associated Conditions
Depends on the risk factors