title: Blood and breath profiles of volatile organic compounds in patients with end-stage renal disease.
abstract: BACKGROUND
  Monitoring of volatile organic compounds (VOCs) in exhaled breath shows great potential as a non-invasive method for assessing hemodialysis efficiency. In this work we aim at identifying and quantifying of a wide range of VOCs characterizing uremic breath and blood, with a particular focus on species responding to the dialysis treatment.
  
  
  METHODS
  Gas chromatography with mass spectrometric detection coupled with solid-phase microextraction as pre-concentration method.
  
  
  RESULTS
  A total of 60 VOCs were reliably identified and quantified in blood and breath of CKD patients. Excluding contaminants, six compounds (isoprene, dimethyl sulfide, methyl propyl sulfide, allyl methyl sulfide, thiophene and benzene) changed their blood and breath levels during the hemodialysis treatment.
  
  
  CONCLUSIONS
  Uremic breath and blood patterns were found to be notably affected by the contaminants from the extracorporeal circuits and hospital room air. Consequently, patient exposure to a wide spectrum of volatile species (hydrocarbons, aldehydes, ketones, aromatics, heterocyclic compounds) is expected during hemodialysis. Whereas highly volatile pollutants were relatively quickly removed from blood by exhalation, more soluble ones were retained and contributed to the uremic syndrome. At least two of the species observed (cyclohexanone and 2-propenal) are uremic toxins. Perhaps other volatile substances reported within this study may be toxic and have negative impact on human body functions. Further studies are required to investigate if VOCs responding to HD treatment could be used as markers for monitoring hemodialysis efficiency.
authors.forename: Paweł
authors.initials: P
authors.lastname: Mochalski
authors.forename: Julian
authors.initials: J
authors.lastname: King
authors.forename: Matthias
authors.initials: M
authors.lastname: Haas
authors.forename: Karl
authors.initials: K
authors.lastname: Unterkofler
authors.affiliation: Breath Research Institute, University of Innsbruck, Rathausplatz 4, A-6850 Dornbirn, Austria. Anton.Amann@i-med.ac.at.
authors.forename: Anton
authors.initials: A
authors.lastname: Amann
authors.forename: Gert
authors.initials: G
authors.lastname: Mayer
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D001944:Breath Tests; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000378:metabolism* / Q000628:therapy*; D008297:Male; D006435:Renal Dialysis / Q000009:adverse effects*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D014511:Uremia / Q000209:etiology* / Q000378:metabolism*; D055549:Volatile Organic Compounds / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D055549:Volatile Organic Compounds