Bacterial aggregation in sepsis

Previous studies have provided evidence that bacterial aggregation occurs in disease processes. In the present report, an assay system was used to demonstrate bacterial aggregation and coaggregation in vitro. The results showed that uropathogens aggregated in urine and saline and formed aggregates attached to uroepithelial cells. The presence of fimbriae and O, K, and H antigens on the cell surface did not appear to correlate with aggregation. Additional studies related to intraabdominal sepsis showed aggregation of aBacteroides fragilis strain and coaggregation betweenBacteroides fragilis andEscherichia coli, suggestive of in vivo interaction. Electron microscopy demonstrated the various aggregation reactions and was particularly effective in showing type 1 fimbriatedEscherichia coli coaggregating with theBacteroides fragilis. The ability of organisms to aggregate and coaggregate appears to have potential significance in health and disease.