[Production of O antigens and antibodies during urinary tract infections due to Escherichia coli (author's transl)].

In 138 adults with monomicrobial E. coli urinary tract infections, IgG coated bacteriuria (ACB) are found in 9/10 acute pyelonephritis, 21/24 chronic pyelonephritis, 2/5 acute prostatitis, and in only 6/99 lower UTI. These urinary antibodies are synthetised localy because IgA-S are found in 75%, in the kidney because humoral IgG antibodies are detected in only 40% of the ACB + patients. O6, O18, O22, O75, are the four most frequent O antigens (47,5%) and no difference were found in the distribution of O serotypes according to ACB production or clinical signs. But rough strains are significantly more frequent in pyelonephritis, suggesting a modification of the bacterial wall. The use of ACB test and O serotyping allows a better follow-up of patients, but relapses with ACB- and reinfection with ACB+ show the complexity of the relation host-E. coli.