One of the most common performed laboratory tests in clinical practice.
Red blood cell casts reflect glomeruli damage.
Normal red blood cells in the urine are round and similar in size and shape.
Bleeding of glomerular origin associated with irregular red blood cells of varying size.
A part of the diagnostic evaluation of urinary symptomatic patients or for monitoring renal or urological diseases.
It is an important component of evaluating asymptomatic patients with essential hypertension and diabetes, and it is a screening test for asymptomatic healthy patients.
The prevalence of microhematuria in asymptomatic patients is common and could be as high as 21%.
Routine urinalysis, by test strip, dipstick, or microscopic examination, is among the most frequently performed clinical laboratory tests.
Tests include analysis of protein, ketones, pH, blood, bilirubin, and urobilinogen, nitrite test used to indicate the presence of bacteria and leukocyte esterase analysis, intended to estimate white blood cells and degree of pyuria.
The routine urinalysis performed by dipstick or microscopic examination is most times ordered for purposes of diagnosing a urinary tract infection.
Has become part of routine medical practice.
Is often obtained for no clear clinical indication.
The detection of clinically irrelevant findings in the urinalysis serves to potentially delay making a correct diagnosis.
The detection of clinically irrelevant findings frequently leads to the prescribing of antibiotics agents for the treatment of asymptomatic bacteriuria.
Asymptomatic bacteriuria has been defined as the presence of at least 10 to the 5th cfu/mL of a uropathogen from 2 consecutive voided urine specimens in women or 1 specimen in men, or >10 to the 2nd cfu/mL of 1 bacterial species from a catheterized urine specimen in women or men, in all cases with absence of local or systemic signs or symptoms of an active infection.
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.
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.
The presence of pyuria accompanying asymptomatic bacteriuria is not an indication for antimicrobial treatment, nevertheless, leukocytes detected in the urine seem to provide rationale to prescribe unnecessary antibiotics.
Asymptomatic bacteriuria in pregnant women, individuals undergoing invasive urologic procedures or elective orthopedic surgery, recipients of renal transplants, and patients with diabetes and profound neutropenia require consideration of antibiotic therapy.
Asymptomatic bacteriuria in pregnant women, leads to a 20- to 30-fold increased risk of pyelonephritis and preterm delivery, low-birth-weight infants, and poor fetal outcomes.
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.
Screening UA for asymptomatic patients for genitourinary tract cancer is not recommended.
Rates of surgical wound or site infection are statistically similar in both treated and untreated bacteriuric patients.
Moreover, in those diagnosed with postoperative infections, the bacterial pathogens cultured from the infected site were distinct from those isolated from the urine preoperatively.
Data remain insufficient to recommend the routine treatment of asymptomatic bacteriuria in diabetic patients, renal transplant recipients, and neutropenic patients.
In the absence of over anticoagulation patients on anticoagulants with any abnormal bleeding is not to be expected and should be evaluated in the usual manner with demonstration of pathology in as as many as 80% of cases.