title: Elevated levels of interleukin 17A and kynurenine in candidemic patients, compared with levels in noncandidemic patients in the intensive care unit and those in healthy controls.
abstract: BACKGROUND
  The interplay between Candida species and pattern recognition receptors, interleukins, kynurenine, and T cells has been studied in murine and ex vivo human studies, but data are lacking from patients with invasive fungal infections. Interleukin 17A (IL-17A) is considered an important component in host defense against Candida infections and is modulated by Candida-induced impairment of tryptophan-kynurenine metabolism.
  
  
  METHODS
  Dectin-1, Toll-like receptor 2, and Toll-like receptor 4 expression; regulatory T cell (Treg) percentages; and interleukin 6, interleukin 10, IL-17A, interleukin 22, interleukin 23, interferon γ, kynurenine, and tryptophan levels were determined in candidemic patients and compared to levels in noncandidemic patients who are in the intensive care unit (ICU) and receiving antibiotic therapy and those in healthy controls, both with and without Candida colonization.
  
  
  RESULTS
  Candidemic patients had significantly higher IL-17A and kynurenine levels, compared with noncandidemic patients, including Candida-colonized ICU patients and healthy controls. Within candidemic patients, time-dependent elevation of IL-17A and kynurenine levels was detected. IL-17A areas under the curve for differentiation between patients with early candidemia and those without candidemia (ICU patients, including Candida-colonized patients, and healthy controls) were between 0.94 (95% confidence interval [CI], .89-.99) and 0.99 (95% CI, .99-1).
  
  
  CONCLUSIONS
  Candidemic patients had significantly higher IL-17A and kynurenine levels, compared with noncandidemic patients. The statistically significant association between IL-17A and kynurenine levels and candidemia suggests their potential as biomarkers for anticipation of invasive candidiasis.
  
  
  BACKGROUND
  NCT00786903.
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine.
authors.forename: Robert
authors.initials: R
authors.lastname: Krause
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine.
authors.forename: Ines
authors.initials: I
authors.lastname: Zollner-Schwetz
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine Center for Internal Medicine, University Hospital Hamburg Eppendorf, Germany.
authors.forename: Helmut J F
authors.initials: HJ
authors.lastname: Salzer
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine.
authors.forename: Thomas
authors.initials: T
authors.lastname: Valentin
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine.
authors.forename: Jasmin
authors.initials: J
authors.lastname: Rabensteiner
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics.
authors.forename: Florian
authors.initials: F
authors.lastname: Prüller
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Raggam
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics.
authors.forename: Andreas
authors.initials: A
authors.lastname: Meinitzer
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Prattes
authors.affiliation: Center for Medical Research.
authors.forename: Beate
authors.initials: B
authors.lastname: Rinner
authors.affiliation: Center for Medical Research.
authors.forename: Heimo
authors.initials: H
authors.lastname: Strohmaier
authors.affiliation: Institute for Medical Informatics, Statistics, and Documentation.
authors.forename: Franz
authors.initials: F
authors.lastname: Quehenberger
authors.affiliation: Experimental and Clinical Cell Therapy Institute, Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Dirk
authors.initials: D
authors.lastname: Strunk
authors.affiliation: Institute of Hygiene, Microbiology, and Environmental Medicine, Medical University of Graz.
authors.forename: Katharina
authors.initials: K
authors.lastname: Heidrich
authors.affiliation: Institute of Hygiene, Microbiology, and Environmental Medicine, Medical University of Graz.
authors.forename: Walter
authors.initials: W
authors.lastname: Buzina
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine.
authors.forename: Martin
authors.initials: M
authors.lastname: Hoenigl
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002175:Candida; D002177:Candidiasis / Q000378:metabolism* / Q000382:microbiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007371:Interferon-gamma / Q000378:metabolism; D020381:Interleukin-17 / Q000378:metabolism*; D007737:Kynurenine / Q000378:metabolism*; D037181:Lectins, C-Type / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism; D051195:Toll-Like Receptor 2 / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000378:metabolism; D014364:Tryptophan / Q000378:metabolism; D055815:Young Adult; D000099181:Dectin-1
chemical_list: D007371:Interferon-gamma; D020381:Interleukin-17; D007737:Kynurenine; D037181:Lectins, C-Type; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D014364:Tryptophan; D000099181:Dectin-1; C508717:IL17A protein, human
keywords: candida; interleukins; kynurenine