Scanning electron microscopy study of Pseudomonas aeruginosa in vivo adherence to rat bladder epithelium

A scanning electron microscopy study was performed to investigate the early phase of in vivo Pseudomonas aeruginosa interaction with rat bladder epithelium. Rapid and heavy adherence was observed when a non-piliated strain of P. aeruginosa was used, but only after brief pretreatment of the urinary bladder with 0.1 N hydrochloric acid. No alteration in the surface morphology was detected in acid treated bladders. Adherence was uniform throughout the bladder with no evidence of trapping of bacteria in the epithelial folds or crypts. Although numerous organisms associated with the epithelial cells appeared to be attached by fibrin-like strands, most adherent bacteria lacked this anchoring mechanism, suggesting more than 1 mechanism of P. aeruginosa adherence to uroepithelial cells.