Immunologic Responses in Urinary-Tract Infections

Abstract

Circulating antibodies develop in both experimental and clinical pyelonephritis. However, the relationship of such antibodies to antibacterial resistance is complex, and conclusions drawn from various observations have been controversial. In experimental pyelonephritis caused by gram-negative bacilli, preimmunization was protective; however, it was nullified by obstructive uropathy. Clinical assessment of antibody response has had two goals: determination of diagnostic value and assessment of protective effects. While a single hemagglutinin titer is of limited value, a significant rise in anti-0 hemagglutinin titer suggests pyelonephritis. In patients with cystitis, titers tend to remain stable. Immunity appears to play little role in recovery, but may be a determinant in selection of organisms involved in reinfection.