title: Positron emission tomography scanning in anti-neutrophil cytoplasmic antibodies-associated vasculitis.
abstract: Tools for evaluation of disease activity in patients with anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) include scoring clinical manifestations, determination of biochemical parameters of inflammation, and obtaining tissue biopsies. These tools, however, are sometimes inconclusive. 2-deoxy-2-[F]-fluoro-D-glucose (FDG) positron emission tomography (PET) scans are commonly used to detect inflammatory or malignant lesions. Our objective is to explore the ability of PET scanning to assess the extent of disease activity in patients with AAV.Consecutive PET scans made between December 2006 and March 2014 in Maastricht (MUMC) and between July 2008 and June 2013 in Brussels (EUH) to assess disease activity in patients with AAV were retrospectively included. Scans were re-examined and quantitatively scored using maximum standard uptake values (SUVmax). PET findings were compared with C-reactive protein (CRP) and ANCA positivity at the time of scanning.Forty-four scans were performed in 33 patients during a period of suspected active disease. All but 2 scans showed PET-positive sites, most commonly the nasopharynx (n = 22) and the lung (n = 22). Forty-one clinically occult lesions were found, including the thyroid gland (n = 4 patients), aorta (n = 8), and bone marrow (n = 7). The amount of hotspots, but not the highest observed SUVmax value, was higher if CRP levels were elevated. Seventeen follow-up scans were made in 13 patients and showed decreased SUVmax values.FDG PET scans in AAV patients with active disease show positive findings in multiple sites of the body even when biochemical parameters are inconclusive, including sites clinically unsuspected and difficult to assess otherwise.
authors.affiliation: From the Clinical and Experimental Immunology, Maastricht University Medical Center (MJK, SAMEGT, PP); Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands (MJK, SAMEGT, JWCT); Department of Internal Medicine, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium (FV, TN, EC); Department of Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands (SV, MJPGVK); Department of Nuclear Medicine, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium (DB); Clinical and Experimental Immunology, Maastricht University, Maastricht (JWCT); and Noordoever Academy, Sint Franciscus Gasthuis, Rotterdam, The Netherlands (JWCT).
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Kemna
authors.forename: Frédéric
authors.initials: F
authors.lastname: Vandergheynst
authors.forename: Stefan
authors.initials: S
authors.lastname: Vöö
authors.forename: Didier
authors.initials: D
authors.lastname: Blocklet
authors.forename: Thomas
authors.initials: T
authors.lastname: Nguyen
authors.forename: Sjoerd A M E G
authors.initials: SAMEG
authors.lastname: Timmermans
authors.forename: Pieter
authors.initials: P
authors.lastname: van Paassen
authors.forename: Elie
authors.initials: E
authors.lastname: Cogan
authors.forename: Marinus J P G
authors.initials: MJPG
authors.lastname: van Kroonenburgh
authors.forename: Jan Willem Cohen
authors.initials: JWC
authors.lastname: Tervaert
mesh_terms: D056648:Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / Q000097:blood / Q000175:diagnosis / Q000000981:diagnostic imaging*; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D015415:Biomarkers; D002097:C-Reactive Protein