title: Evaluation of the Metabolic Activity of Echinococcus multilocularis in Rodents Using Positron Emission Tomography Tracers.
abstract: OBJECTIVE
  2-Deoxy-2-[(18)F]fluoro-D-glucose ([(18)F]FDG) has been used as a standard clinical positron emission tomography (PET) tracer for the follow-up of the rare but life-threatening parasitic disease alveolar echinococcosis (AE). Given that the disease is endemic in many countries in the northern hemisphere and the diagnosis is still challenging, the aim of our study was to evaluate further clinically relevant PET tracers as possible diagnostic tools for AE in vitro and in vivo.
  
  
  METHODS
  Various clinically used PET tracers were evaluated in vitro and assessed in an in vivo AE animal model based on PET/magnetic resonance (MR) measurements.
  
  
  RESULTS
  In vitro binding assays displayed high uptake of [(18)F]FDG in a cell suspension of E. multilocularis tissue, whereas 3'-deoxy-3'-[(18)F]fluorothymidine ([(18)F]FLT) and [(11)C]choline were found to be taken up strongly by E. multilocularis vesicles. [(18)F]FDG and [(18)F]FLT displayed an elevated uptake in vivo, which appeared as several foci throughout the parasite tissue as opposed to [(18)F]fluoro-azomycinarabinofuranoside ([(18)F]FAZA) and [(11)C]choline.
  
  
  CONCLUSIONS
  Our data clearly demonstrate that the clinically applied PET tracer [(18)F]FDG is useful for the diagnosis and disease staging of AE but also has drawbacks in the assessment of currently inactive or metabolically weak parasitic lesions. The different tested PET tracers do not show the potential for the replacement or supplementation of current diagnostic strategies. Hence, there is still the need for novel diagnostic tools.
authors.affiliation: Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Röntgenweg 13, 72076, Tübingen, Germany.
authors.forename: Anna-Maria
authors.initials: AM
authors.lastname: Rolle
authors.forename: Peter T
authors.initials: PT
authors.lastname: Soboslay
authors.forename: Gerald
authors.initials: G
authors.lastname: Reischl
authors.forename: Wolfgang H
authors.initials: WH
authors.lastname: Hoffmann
authors.forename: Bernd J
authors.initials: BJ
authors.lastname: Pichler
authors.forename: Stefan
authors.initials: S
authors.lastname: Wiehr
mesh_terms: D000818:Animals; D004443:Echinococcosis / Q000000981:diagnostic imaging* / Q000378:metabolism*; D048210:Echinococcus multilocularis / Q000378:metabolism*; D005260:Female; D005849:Gerbillinae; D008279:Magnetic Resonance Imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000378:metabolism* / Q000493:pharmacokinetics
chemical_list: D019275:Radiopharmaceuticals