Figure

Urine test strips. Normal urine is sterile, but suprapubic aspiration of the bladder, which is by no means a routine procedure, would be the only way of proving it. Urinary tract infection (UTI) cannot be identified simply by the presence of bacteria in a voided specimen, as micturition flushes saprophytic urethral organisms along with the urine. Thus a certain number of colony-forming units of uropathogens are to be expected in the urine sample. Midstream collection is the most common method of urine sampling used in adults. When urine cannot be studied without delay, it must be stored at 4°C until it is sent to the bacteriology laboratory. The urine test strip is the easiest means of diagnosing UTI qualitatively. This test detects leukocytes and nitrites. Simultaneous detection of the two is highly suggestive of UTI. This test is 95% sensitive and 75% specific, and its negative predictive value is close to 96% [3]. The test does not, however, detect such bacteria as Staphyloccocus saprophyticus, a strain responsible for some 3% to 7% of UTIs. Thus, treating UTI solely on the basis of test strip risks failure in about 15% of simple community-acquired infections and a much larger proportion of UTIs acquired in a hospital.

Schematic set up of a dip-slide container

Schematic set up of a dip-slide container

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