Development of X-ray micro-focus computed tomography to image and quantify biofilms in central venous catheter models in vitro
Development of X-ray micro-focus computed tomography to image and quantify biofilms in central venous catheter models in vitro
Bacterial infections of central venous catheters (CVCs) cause much morbidity and mortality, and are usually diagnosed by concordant culture of blood and catheter tip. However, studies suggest that culture often fails to detect biofilm bacteria. This study optimises X-ray micro computed tomography (X-ray µCT) for the quantification and determination of distribution and heterogeneity of biofilms in in vitro central venous catheter (CVC) model systems.
Bacterial culture and scanning electron microscopy (SEM) were used to detect Staphylococcus epidermidis ATCC 35984 biofilms grown on catheters in vitro in both flow and static biofilm models. Alongside this, X-ray µCT techniques were developed in order to detect biofilms inside CVCs. Various contrast agent stains were evaluated using energy dispersive X-ray spectroscopy (EDS) to further optimise these methods. Catheter material and biofilm were segmented using a semi-automated MATLAB script and quantified using the Avizo Fire software package.
X-ray µCT was capable of distinguishing between the degree of biofilm formation across different segments of a CVC flow model. EDS screening of single and dual compound contrast stains identified 10 nm gold and silver nitrate as the optimum contrast agent for X-ray µCT. This optimised method was then demonstrated to be capable of quantifying biofilms in an in vitro static biofilm formation model, with a strong correlation between biofilm detection via SEM and culture.
X-ray µCT has good potential as a direct, non-invasive, non-destructive technology to image biofilms in CVCs, as well as other in vivo medical components in which biofilms accumulate in concealed areas.
1629-1640
Niehaus, Wilmari
9038d4cc-fdec-470b-ae6a-da0de1ae4070
Howlin, Robert
f3c84990-6196-47d4-ad8a-80954ea46c7f
Johnston, David A.
b41163c9-b9d2-425c-af99-2a357204014e
Bull, Daniel
3569ba02-89de-4398-a14d-02c3f9b4eab2
Jones, Gareth L.
fdb7f584-21c5-4fe4-9e57-b58c78ebe3f5
Calton, Elizabeth
92094a21-e07f-4f14-880c-65a51a7be359
Mavrogordato, Mark
f3e0879b-118a-463a-a130-1c890e9ab547
Clarke, Stuart
f7d7f7a2-4b1f-4b36-883a-0f967e73fb17
Thurner, Philipp
ab711ddd-784e-48de-aaad-f56aec40f84f
Faust, Saul
f97df780-9f9b-418e-b349-7adf63e150c1
Stoodley, Paul
08614665-92a9-4466-806e-20c6daeb483f
1 September 2016
Niehaus, Wilmari
9038d4cc-fdec-470b-ae6a-da0de1ae4070
Howlin, Robert
f3c84990-6196-47d4-ad8a-80954ea46c7f
Johnston, David A.
b41163c9-b9d2-425c-af99-2a357204014e
Bull, Daniel
3569ba02-89de-4398-a14d-02c3f9b4eab2
Jones, Gareth L.
fdb7f584-21c5-4fe4-9e57-b58c78ebe3f5
Calton, Elizabeth
92094a21-e07f-4f14-880c-65a51a7be359
Mavrogordato, Mark
f3e0879b-118a-463a-a130-1c890e9ab547
Clarke, Stuart
f7d7f7a2-4b1f-4b36-883a-0f967e73fb17
Thurner, Philipp
ab711ddd-784e-48de-aaad-f56aec40f84f
Faust, Saul
f97df780-9f9b-418e-b349-7adf63e150c1
Stoodley, Paul
08614665-92a9-4466-806e-20c6daeb483f
Niehaus, Wilmari, Howlin, Robert, Johnston, David A., Bull, Daniel, Jones, Gareth L., Calton, Elizabeth, Mavrogordato, Mark, Clarke, Stuart, Thurner, Philipp, Faust, Saul and Stoodley, Paul
(2016)
Development of X-ray micro-focus computed tomography to image and quantify biofilms in central venous catheter models in vitro.
Microbiology, 162 (9), .
(doi:10.1099/mic.0.000334).
(PMID:27384949)
Abstract
Bacterial infections of central venous catheters (CVCs) cause much morbidity and mortality, and are usually diagnosed by concordant culture of blood and catheter tip. However, studies suggest that culture often fails to detect biofilm bacteria. This study optimises X-ray micro computed tomography (X-ray µCT) for the quantification and determination of distribution and heterogeneity of biofilms in in vitro central venous catheter (CVC) model systems.
Bacterial culture and scanning electron microscopy (SEM) were used to detect Staphylococcus epidermidis ATCC 35984 biofilms grown on catheters in vitro in both flow and static biofilm models. Alongside this, X-ray µCT techniques were developed in order to detect biofilms inside CVCs. Various contrast agent stains were evaluated using energy dispersive X-ray spectroscopy (EDS) to further optimise these methods. Catheter material and biofilm were segmented using a semi-automated MATLAB script and quantified using the Avizo Fire software package.
X-ray µCT was capable of distinguishing between the degree of biofilm formation across different segments of a CVC flow model. EDS screening of single and dual compound contrast stains identified 10 nm gold and silver nitrate as the optimum contrast agent for X-ray µCT. This optimised method was then demonstrated to be capable of quantifying biofilms in an in vitro static biofilm formation model, with a strong correlation between biofilm detection via SEM and culture.
X-ray µCT has good potential as a direct, non-invasive, non-destructive technology to image biofilms in CVCs, as well as other in vivo medical components in which biofilms accumulate in concealed areas.
Text
Manuscript PSv1.docx
- Accepted Manuscript
More information
Accepted/In Press date: 5 July 2016
e-pub ahead of print date: 1 September 2016
Published date: 1 September 2016
Organisations:
Faculty of Medicine, Faculty of Health Sciences, Engineering Mats & Surface Engineerg Gp, Bioengineering Group, nCATS Group
Identifiers
Local EPrints ID: 398578
URI: http://eprints.soton.ac.uk/id/eprint/398578
ISSN: 1350-0872
PURE UUID: 4563502e-9a00-4563-ab3a-9653d601c4b6
Catalogue record
Date deposited: 27 Jul 2016 09:21
Last modified: 15 Mar 2024 05:46
Export record
Altmetrics
Contributors
Author:
Wilmari Niehaus
Author:
Robert Howlin
Author:
David A. Johnston
Author:
Gareth L. Jones
Author:
Elizabeth Calton
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics