[The etiology of urinary tract infections]

The Authors have planned a program in order to file and elaborate with a computer the results of urine cultures. From 8.600 specimens, about 86% were negative or doubtful. The data obtained from 1201 positive cultures were processed in order to state the absolute and relative frequency of the bacterial species isolated and their distribution according to their genera, antibiotic resistence, month and sex. Among the most representative species the pattern of antibiotic resistence was surveyed. E. coli shows very high frequency (38%). The frequency of Pseudomonas increases while staphylococci frequency decreases as compared with the previous statements of various Authors. The analysis of the antibiotic sensitivity spectrum of 534 specimens shows that about 50% of E. coli strains are sensitive to 10, 11 and 12 antibiotics and their pattern of resistence involves no more than 9 antibiotics; on the contrary more than 60% of Pseudomonas and Proteus rettgeri are resistant to 10, 11 or 12 antibiotics and at any rate to no less than seven. Enterobacter and Proteus mirabilis present an intermediate pattern of resistence.