Abstract: | Various bacteria with pili are able to agglutinate human and animal red blood cells. Hemagglutinating activity of 131 strains of Escherichia coli isolated from respiratory tract (24 strains), urine (64 strains), feces (36 strains) and blood (7 strains) were tested using human type A, guinea pig, bovine and chicken erythrocytes. Concerning the hemagglutination activity for erythrocytes from at least one of four species (human, guinea pig, bovine, chicken), the strains isolated from respiratory tract showed a higher level than those isolated from feces (p less than 0.01) or those isolated from blood (p less than 0.1). Agglutination of human erythrocytes: Of 131 strains, mannose-sensitive agglutination was observed in 31 strains, mannose-resistant agglutination in 40 strains and non-agglutination in 60 strains. More agglutinated strains were isolated from the respiratory tract than those isolated from blood but not with statistical significance (p less than 0.1). Agglutination of guinea pig erythrocytes: Of 131 strains, mannose-sensitive agglutination was observed in 56 strains, mannose-resistant agglutination in 10 strains and non-agglutination in 65 strains. More agglutinated strains were isolated from the respiratory tract than from urine, feces and blood (p less than 0.01), and of those, 89% were mannose-sensitive agglutination. Agglutination of bovine erythrocytes: Of the 131 strains, mannose-sensitive agglutination was observed in 4 strains, mannose-resistant agglutination in 6 strains and non-agglutination in 121 strains. Therefore, only a few agglutinated strains were seen.(ABSTRACT TRUNCATED AT 250 WORDS) |