Immunologic Studies in Urinary Tract Infections

Hemagglutinins (HA) to O antigens from bacteria in urine were measured in serial serum specimens from patients with urinary tract infections. Twofold or greater HA rises were found in 51 of 105 bacteria from patients with acute infections of varying severity. HA rises to specific Escherichia, particularly strains possessing O antigens 4 and 6, were found primarily in patients with temperatures greater than 101° and in those with overt acute pyelonephritis. In these persons and in patients with chronic pyelonephritis high HA titers to heterologous E. coli O4 and O6 antigens were also found. Serologic and cultural findings of other Gram-negative bacteria were more randomly distributed. These serologic methods offer promise in documenting urinary tract infections and separating such severe infections as acute and chronic pyelonephritis from cystitis.