Immunology of Escherichia coli: K Antigen and Its Relation to Urinary-Tract Infection

Abstract

Escherichia coli strains O1, O2, O6, and O7 from the urine of 101 girls with urinary-tract infection (UTI) as well as from stools of 250 healthy schoolchildren were tested for the presence of K2a,2c, K13, and K1 antigen. The amount of K antigen was determined by crossed immunoelectrophoresis and by the hemagglutination inhibition technique. K antigen was found significantly more often and in significantly greater amounts among E. coli from the urine of patients with pyelonephritis than among the strains from children with cystitis or from stools of healthy schoolchildren.