Increased sensitivity of bacterial detection in cerebrospinal fluid by fluorescent staining on low-fluorescence membrane filters.
A membrane-filter-based, fluorescent Gram stain method for bacterial detection in cerebrospinal fluid samples was developed and evaluated as a rapid, sensitive alternative to standard Gram stain protocols. A recently developed, modified version of the aluminium oxide membrane Anopore with low-fluorescence optical properties showed superior performance in this application. Other aspects of the fluorescent Gram stain system that were evaluated include membrane filter selection, strategies to reduce fluorescence fading and the effect of patient blood cells on bacterial detection in the fluorescently stained cerebrospinal fluid samples. The combination of the membrane filter's bacteria-concentrating ability and absolute retention along with high-contrast, fluorescent Gram discriminating dyes enabled rapid bacterial detection and Gram discrimination, with a 1-1.5 order of magnitude increase in the bacterial concentration limit of detection.
Durtschi
Jacob D
JD
ARUP Institute for Clinical and Experimental Pathology1 and Department of Pathology2, University of Utah, Salt Lake City, UT 84108, USA.
Erali
Maria
M
ARUP Institute for Clinical and Experimental Pathology1 and Department of Pathology2, University of Utah, Salt Lake City, UT 84108, USA.
Bromley
L Kathryn
LK
ARUP Institute for Clinical and Experimental Pathology1 and Department of Pathology2, University of Utah, Salt Lake City, UT 84108, USA.
Herrmann
Mark G
MG
ARUP Institute for Clinical and Experimental Pathology1 and Department of Pathology2, University of Utah, Salt Lake City, UT 84108, USA.
Petti
Cathy A
CA
ARUP Institute for Clinical and Experimental Pathology1 and Department of Pathology2, University of Utah, Salt Lake City, UT 84108, USA.
Smith
Roger E
RE
ARUP Institute for Clinical and Experimental Pathology1 and Department of Pathology2, University of Utah, Salt Lake City, UT 84108, USA.
Voelkerding
Karl V
KV
ARUP Institute for Clinical and Experimental Pathology1 and Department of Pathology2, University of Utah, Salt Lake City, UT 84108, USA.
D001431:Bacteriological Techniques; D002555:Cerebrospinal Fluid / Q000382:microbiology*; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000302:isolation & purification; D005374:Filtration / Q000295:instrumentation / Q000379:methods; D005453:Fluorescence; D005840:Gentian Violet; D006801:Humans; D008851:Micropore Filters; D008856:Microscopy, Fluorescence / Q000379:methods*; D009930:Organic Chemicals / Q000378:metabolism; D010619:Phenazines; D012680:Sensitivity and Specificity; D013194:Staining and Labeling / Q000379:methods*; D013211:Staphylococcus aureus / Q000302:isolation & purification
C035863:Gram's stain; D009930:Organic Chemicals; D010619:Phenazines; C103389:SYTO 9; D005840:Gentian Violet