[Cytobacteriologic examination of the urine. Execution. Interpretation]

Bacteriological examination of urine is sufficient to assert the presence of a urinary tract infection (UTI). Specimens must be collected under strictly aseptic conditions. The midstream jet method is the best, but when it is not feasible bladder puncture, sterile pouches or catheterization may be used. The urine obtained must be correctly preserved and transported. In the practitioner's office, UTI can be detected by reagent strips or agar-coated plates. In the laboratory, direct examination is used to count leucocytes and characterize Gram-positive and Gram-negative bacteria. Bacteriuria at 10(5)/ml is significant of infection. The micro-organisms most frequently responsible for UTI are Enterobacteriaceae (mostly E. coli), Proteus mirabilis, Klebsiella spp. and staphylococci (Staph. aureus, Staph. saprophyticus, Staph. epidermidis). In most cases disc sensitivity tests are indispensable, but bacteriological examination of urine is not always needed in women with uncomplicated lower urinary tract infection.