Scanning electron microscopy of bacterial biofilms on indwelling bladder catheters.
Fifty Foley bladder catheters that had been indwelling for periods ranging from 3 to 83 days (mean 35 days) were examined for the presence of bacterial biofilm. Scanning electron microscopy on freeze-dried cross-sections and fixed, critical point-dried longitudinal sections revealed biofilm formation on the luminal surfaces of 44 of the catheters. Culture of urine samples and sonicates from catheters revealed that the prevalence of bacteriuria was less than that of catheter colonization. A wide range of nosocomial species were found colonizing the catheters, Escherichia coli being most often isolated. The bacterial composition of the biofilms ranged from single species to mixed communities containing up to four species. There was no relationship between the length of time that the catheter had been in situ and the extent of biofilm formation. The biofilms varied in thickness from 3 to 490 microns and were visible as layers of bacterial cells up to about 400 cells deep, embedded in a matrix.
Ganderton
L
L
School of Pure and Applied Biology, University of Wales College of Cardiff, UK.
Chawla
J
J
Winters
C
C
Wimpenny
J
J
Stickler
D
D
D001422:Bacterial Adhesion; D002408:Catheters, Indwelling; D004926:Escherichia coli / Q000302:isolation & purification*; D005614:Freeze Fracturing; D006801:Humans; D008855:Microscopy, Electron, Scanning; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification*; D013289:Streptococcaceae / Q000302:isolation & purification*; D001743:Urinary Bladder