[The microbiological exam of the urine: what significance in urinary tract infections?].

11,829 urine cultures, coming from the Pediatrics Department of Florence and other hospital divisions for adults in the period 1st of July-31st of December 1990, have been examined in the Bacteriology and Virology Laboratory of the University Hospital of Florence. Besides illustrating various methods of drawing, preservation and transport of the urinary specimen, the authors showed the incidence of bacterial species responsible of urinary tract infections (U.T.I.). E. coli was showed to be the most frequently isolated bacterial strain, followed by Streptococcus faecalis and Proteus indole negative. The incidence of fimbriated E. coli infections was studied in pediatric and adult patients with urinary tract infections; a higher isolation frequency of fimbriated E. coli was showed in pediatric patients and in these patients the correlation was studied between the presence of fimbriated E. coli and the severity of infection (pyelonephritis, recurrent U.T.I.). The percentages of resistance of the isolated strains against the most common chemotherapies was also showed, studying their variations, for some chemotherapies, during about twenty years.