title: Development of a novel method for detection of Clostridium difficile using HS-SPME-GC-MS.
abstract: OBJECTIVE
  A novel method has been developed that allows successful differentiation between Clostridium difficile culture-positive and culture-negative stool samples based on volatile organic compound (VOC) evolution and detection by headspace solid-phase microextraction coupled with gas chromatography mass spectrometry (HS-SPME-GC-MS).
  
  
  RESULTS
  The method is based on the activation of p-hydroxyphenylacetate decarboxylase produced by Cl. difficile and the detection of a specific VOC, that is 2-fluoro-4-methylphenol from an enzyme substrate. In addition, other VOCs were good indicators for Cl. difficile, that is isocaproic acid and p-cresol, although they could not be used alone for identification purposes. One hundred stool samples were tested, of which 77 were positive by culture. Detection using HS-SPME-GC-MS allowed confirmation of the presence of Cl. difficile within 18 h with a sensitivity and specificity of 83·1 and 100%, respectively.
  
  
  CONCLUSIONS
  It is recommended that this new approach could be used alongside conventional methods for Cl. difficile detection, including toxin detection methods, which would allow any false-negative results to be eliminated.
  
  
  CONCLUSIONS
  The ability to identify Cl. difficile-positive stool samples by the analysis of VOCs could allow the development of a VOC detection device which could allow rapid diagnosis of disease and hence prompt treatment with appropriate antibiotics.
authors: Department of Applied Sciences, Northumbria University, Newcastle upon Tyne, UK.
authors: E
authors: E
authors: Tait
authors: K A
authors: KA
authors: Hill
authors: J D
authors: JD
authors: Perry
authors: S P
authors: SP
authors: Stanforth
authors: J R
authors: JR
authors: Dean
mesh_terms: D016360:Clostridioides difficile / Q000737:chemistry / Q000302:isolation & purification*; D003408:Cresols / Q000032:analysis; D005243:Feces / Q000382:microbiology; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D052617:Solid Phase Microextraction; D055549:Volatile Organic Compounds / Q000032:analysis
chemical_list: D003408:Cresols; D055549:Volatile Organic Compounds
keywords: Clostridium difficile; HS-SPME-GC-MS; p-hydroxyphenylacetate decarboxylase enzyme; specificity; stool samples