Immunization against retrograde pyelonephritis. III. Vaccination against chronic pyelonephritis due to Escherichia coli.

Vaccination with formalin-treated cells of Escherichia coli serotype O6 protected against unilateral retrograde pyelonephritis due to E. coli O6 in rats with partial ureteral obstruction. This protection was manifested not only by less parenchymal destruction and shrinkage of the pyelonephritic left kidney, but also by less secondary pyelonephritis and compensatory hypertrophy in the opposite right kidney. Vaccinated rats eliminated E. coli from the kidney more rapidly, but even when infection persisted in the kidney, the chronic pyelonephritis was less severe in vaccinated rats. High levels of antibody to E. coli lipopolysaccharide were found in vaccinated animals and may have contributed to protection. These results raise the question of whether vaccination ought to be considered for patients predisposed to chronic bacterial pyelonephritis.