[Escherichia coli o serotyping in different patient groups with urinary tract infections (author's transl)].

Using 44 anti-O sera 789 Escherichia coli strains isolated from the urine of patients with urinary tract infections were typed. Of the 119 E. coli strains from the urine of children, 49.6% were O-typable; only 3.4% were rough strains. Of 357 strains from pregnant women, 47% were O-typable; 12.1% were rough strains. The largest proportion of O-typable E. coli strains was found among 314 strains isolated from adults with recurrent urinary tract infections (55.4% of the 314 strains); 8% were rough strains. The higher proportion of E. coli rough strains in adults, including pregnant women, indicate that once a pyelonephritis process has been established by virulent smooth strains in childhood, it can be sustained by rough strains at a later stage. Certain O serotypes were found to occur with a variable frequency in the individual patient groups. Enteropathogenic E. coli strains were seldom found in any of the three groups.