True about bacteriuria is: March 2007

Ans. C: More than 1 lac colony forming units/ml of mid stream urine Bacteriuria denotes the presence of bacteria in urine not due to contamination from urine sample collection. Urine is normally a sterile bodily fluid, not containing bacteria. Bacteria in the urine, especially gram-negative rods, usually indicate a urinary tract infection (either cystitis or pyelonephritis), although bacteriuria can also occur in prostatitis. Escherichia coli are the most common bacterium isolated from urine samples. Bacteria can be detected with a dipstick test for nitrite or by urinary microscopy, although bacterial culture remains the most specific and formal test (the golden standard). Bacteriuria can be confirmed if a single bacterial species is isolated in a concentration greater than 1,00,000 colony forming units per millilitre of urine in clean-catch midstream urine specimens (one for men, two consecutive specimens with the same bacterium for women). For urine collected bladder catheterisation, the threshold is 100 colony forming units of a single species per millilitre. Asymptomatic bacteriuria is bacteriuria without accompanying symptoms of a urinary tract infection (such as frequent urination, painful urination or fever). It is more common in women, in the elderly, in residents of long-term care facilities, and in patients with diabetes, bladder catheters and spinal cord injuries. Patients with a long-term Foley catheter uniformly show bacteriuria.