Ultrastructural Study of Microbiologic Colonization of Urinary Catheters

Urology. 1989 Nov;34(5):284-91. doi: 10.1016/0090-4295(89)90327-0.


We examined ten urinary catheters, associated with catheter-related urinary tract infections, by scanning and transmission electron microscopy to study the morphology of bacterial adherence. We confirmed that the bacteria associated with catheter-associated urinary tract infections grow in glycocalyx-enclosed microcolonies in a biofilm on the catheter surface. The bacterial populations demonstrated a heterogeneity that was not evident from the culture results, and it was demonstrated that only a small proportion of the microorganisms, including fungi, identified morphologically by scanning or transmission electron microscopy are recovered by routine culture methods. The persistence of the bacterial pathogens in catheter-associated infection, even in the face of antibiotic treatment, may be attributed to their adherent mode of growth in protected biofilms and their production of extensive enveloping anionic glycocalyces.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Adhesion*
  • Bacterial Infections / etiology*
  • Bacterial Infections / microbiology
  • Female
  • Glycoproteins / analysis
  • Humans
  • Male
  • Microscopy, Electron
  • Microscopy, Electron, Scanning
  • Polysaccharides / analysis
  • Urinary Catheterization* / adverse effects
  • Urinary Tract Infections / etiology*
  • Urinary Tract Infections / microbiology


  • Glycoproteins
  • Polysaccharides