Distinct Eicosanoid Profile in Exhaled Breath Condensates from Granulomatosis with Polyangiitis (wegener’s) Patients

IntroductionGranulomatosis with polyangiitis (GPA, Wegener’s) is asystemic vasculitis affecting mostly small vessels, typicallyinvolving the upper respiratory tract, lungs, and kidneys.Together with microscopic polyangiitis, eosinophilic gran-ulomatosis with polyangiitis (Churg–Strauss syndrome),and renal-limited vasculitis, it commonly shows circulatingantineutrophil cytoplasmic antibodies (ANCA). As such, itis typically referred to as an ANCA-associated vasculitis [1,2]. The pathogenesis of GPA has not been fully elucidated,although the interaction between ANCA and neutrophilsseems pivotal in initiating and supporting an inflammatoryreaction with subsequent cytokine, complement, and endo-thelium involvement [3]. The hallmark of the respiratorytract pathology is granulomatous inflammation, in which theeicosanoid derivatives play an important role. Clinical diag-nostics often requires an invasive approach, i.e., open lungbiopsy, bronchoalveolar lavage, or bronchoscopy-guidedbiopsies. Recently, a noninvasive diagnostic method of therespiratory tract examination was introduced; namely, ex-haled breath condensate (EBC) analysis. We have previous-ly described a highly specific increase in 12-lipoxygenaseproduct (12-HETE) in EBC samples of eosinophilic withpolyangiitis patients [4]. We wondered if ascertainment ofeicosanoid profile in EBC from GPA patients could help innoninvasive diagnostics of GPA.Patients and methodsPatientsWe enrolled 27 patients with GPA treated in the Departmentof Medicine of the University Hospital, JagiellonianUniversity Medical College. The control group consistedof 30 healthy volunteers recruited from the hospital employ-ees with similar gender distribution. GPA was diagnosedaccording to the American college of rheumatology criteria,andall patients werec-ANCA positive [5].The Birminghamvasculitis activity score (BVAS v.3, range 0–63 points) [6]was used to assess activity of GPA; results above threeindicated active disease. All subjects studied gave informedwritten consent to participate. The study protocol compliedwith the Helsinki Declaration and was approved by theJagiellonian University ethics committee.Exhaled breath condensate collection and analysisEBC were collected with EcoScreen I Jaeger® condensingchamber (GmbH Hoechberg, Germany) according to theATS/ERSrecommendations[ 7].CollectedEBC(1–2mlwith-in 15 min) was immediately stored at −80 °C until analysis.High-performance liquid chromatography tandem massspectrometry (HPLC–MS/MS; Qtrap 4000, AppliedBiosystems, Foster City, CA, USA) or gas chromatogra-phy–mass spectrometry (GC–MS; Engine 5989B series IIHewlett Packard, Palo Alto, CA, USA) were used for thequantification of substances with a stable isotope dilutionmethod [8]. The detection levels for the eicosanoids (inpicograms per milliliter) were as previously described [8,9], and palmitic acid (PA)—abundant in EBC—was usedfor a correction of dilution factor. Eicosanoids were