New haemagglutinating fimbriae on Escherichia coli strains isolated from urine

The haemagglutination patterns of 255 urinary Escherichia coli isolates were examined with human (A, Rh+), bovine, chicken and guinea pig erythrocytes in the presence and absence of D-mannose. The strains were divided into four groups according to their haemagglutination properties. About 40% of the isolates agglutinated human red blood cells in the presence of D-mannose. The haemagglutinin of one of these, E. coli O18a, c:K-strain No. 119 was stable, temperature sensitive, did not develop at 18°C and could be isolated by the methods used for the production of fimbriae. Electron microscopy showed fimbriae on the surface of strain No. 119. An absorbed serum prepared from a derivative cured of haemagglutinating property (No. 119/l) agglutinated all the strains haemagglutinating human erythrocytes in the presence of mannose, but none of those having other haemagglutination patterns. Serologically, the antigen of No. 119 is independent of the K88, K99, '987' and CF I factors and shows some relationship to CF II.