Value of non-identified ANCA (non-PR3, non-MPO) in the diagnosis of granulomatosis with polyangiitis (Wegener's granulomatosis). Issue 5 (3rd September 2017)

• Record Type: Journal Article
• Authors: Givaudan, Mélanie; Vandergheynst, Frédéric; Stordeur, Patrick; Ocmant, Annick; Melot, Christian; Gangji, Valérie; Soyfoo, Muhammad S.
• Is Part Of: Acta clinica belgica. Volume 72:Issue 5(2017)
• Page Start: 313
• Page End: 317
• Publication Date: 2017-09-03
• Subjects: ANCA -- non-identified -- granulomatosis with polyangiitis -- vasculitis -- diagnosis -- autoimmune; Clinical medicine -- Periodicals; Diagnosis, Laboratory -- Periodicals; 616.005
• DOI: 10.1080/17843286.2016.1275374
• Languages: English
• ISSNs: 1784-3286

Abstract

Abstract : Objective : Determine the frequency of granulomatosis with polyangiitis (GPA) associated with non-identified ANCA (non-MPO, non-PR3 ANCA) and secondarily compare their clinic with GPA associated with MPO-positive or PR3-positive ANCA. Methods: In a monocentric retrospective observational study, clinical data of 398 patients with non-identified ANCA (titer of ANCA at least 1/80 by immunofluorescence on ethanol fixed PMN) was gathered over a period of 6 years. GPA patients from this population were compared with GPA patients with identified ANCA on the basis of clinical, biological, immunological and histological features. Results: The most common diseases associated with non-identified ANCA were inflammatory bowel diseases accounting for 17% of diseases. GPA accounted for only 1.8% of cases. There were no significant differences in terms of clinical and histological characteristics between GPA with non-identified ANCA and GPA with identified ANCA, but significantly higher CRP levels were observed in GPA patients with identified ANCA ( p = 0.005). Localized disease (ear, nose and throat and/or lung involvement without any other systemic involvement) was more frequent in the group of GPA with nonidentified ANCA ( p = 0.047) as compared to GPA with identified ANCA. This explains that the former group of patients was less frequently treated by cyclophosphamide than the latter ( p = 0.016). Conclusion: GPA with non-MPO, non-PR3 ANCAs is relatively rare. Our study suggests that GPA with nonidentified ANCA differs from GPA with identified ANCA by the frequency of localized forms.