[Distribution of the O-group of "E coli" isolated in urinary tract infections (author's transl)]. / La distribuzione di frequenza di sierogruppi di "E coli" nelle infexioni urinarie.

The distribution of the O-groups of E. coli isolated in urinary tract infections by several italian and foreing Authors are reviewed and compared with the distribution obtained by us in the O-grouping of 300 strains isolated during 1976 in hospital and in surgery. Our results are similar to those of above-mentioned Authors. In fact O6, O75 and O2 groups are the most frequent; besides for the first time a considerable number of "enteritogenic" groups has been isolated and the most frequent of them was the O126. According to the results, the theory of specific pathogenicity could be supported by the high frequency of the O6, O75 and O2 groups; the presence of other groups could justify the theory of prevalence.

[Serological typing and antibiotic resistance in urinary "E. coli" (author's transl)]. / Tipizzazione sierologiga ed antibiotico-resistenza di "E. coli" urinari.

The distribution of the O-groups of E. coli isolated in rivers (Arno, Serchio) and other surface waters is compared with the distribution of those isolated in urinary tract infections. The "chi square" test indicates a good correlation between the observed and expected frequencies in these two distributions, for all the O-groups, but six. Two of these (08 and 019) are significantly more frequent in the waters than in urinary isolates and four (02, 01, 018 and 075) viceversa. The O-group 6 its the most frequent in both, however the observed frequency in urine is greater than the expected one as regards the frequency in water isolates. These results would confirm, with the mentioned exceptions, the prevalence theory. The different patterns of resistance to the antibiotics suggest us to research a possible correlation between the antibotic resistance and the most frequent isolated O-groups. But no evidence of such correlation is demonstrated.