Background

ANCA-associated vasculitides (AAV, including granulomatosis with polyangiitis [GPA], microscopic polyangiitis [MPA] and eosinophilic granulomatosis with polyangiitis [EGPA]) are potentially life-threatening vasculitides characterized by inflammation of small-sized blood vessels with resultant ischemic events, hemorrhagic events or both [1]. Their rarity and the heterogeneous nature of AAV mean that the management of individual patients can be extremely challenging and may vary markedly across different geographical regions and medical disciplines. Existing guidelines were initially developed prior to 2010, most have not yet been updated, and did not take into account the specificities of health care system delivery, access to services and drug treatments in Canada [2–11].

The Canadian Vasculitis research network (CanVasc) was created in November 2010 and its core committee includes physicians of different specialties, though primarily rheumatologists and nephrologists. One of the first major objectives of CanVasc was the development of recommendations for the management of patients with AAV within Canada, based on a synthesis of existing international guidelines, supporting evidence and expert consensus of a national Canadian AAV clinical and research network.

Contexte

Les vascularites associées aux ANCA (les VAA, incluant la granulomatose avec polyangéite [GPA], la polyangéïte microscopique [MPA], et la granulomatose éosinophilique avec polyangéite [EGPA]) sont des vascularites caractérisées par une inflammation de la paroi des vaisseaux sanguins de petit calibre, aboutissant à des complications ischémiques ou hémorragiques, et qui mettent souvent en jeu le pronostic vital. Leur rareté, de même que leur présentations cliniques variées, rendent la prise en charge des patients extrêmement ardue, surtout si elle diffère selon les régions géographiques et les disciplines médicales. Les recommandations internationales de prise en charge des VAA existantes ont été développées avant 2010; la plupart n’ont pas encore été mises à jour et aucune ne tenait compte des spécificités de prestation des soins, d’accès aux services et aux divers traitements pharmacologiques dans le réseau de santé canadien.

Le groupe de recherche canadien sur les vascularites (CanVasc) a été créé en novembre 2010. Il est constitué de médecins de diverses spécialités, quoique surtout des rhumatologues et néphrologues. L’un des objectifs principaux de CanVasc était l’élaboration de recommandations de prise en charge des patients atteints de VAA au Canada, en se basant sur les recommandations internationales déjà existantes, les autres preuves scientifiques et publications dans le domaine des VAA, et un processus avec plusieurs étapes afin d’aboutir à un consensus.

Methods

Prior to initiating the development of these recommendations, a national Needs Assessment Questionnaire was disseminated to identify the specific areas of need, possible knowledge gaps and outline key questions [12]. The international existing clinical practice guidelines and consensus statements on the management of AAV published in English or French between 2006 and May 2014 were then reviewed, in addition to Cochrane library and PubMed Medline searches for all therapeutic studies published after the 2009 European League against Rheumatism/European Vasculitis Society (EULAR/EUVAS) recommendations and May 2014. The first draft of these recommendations was developed by the core group of the CanVasc recommendation working group and included 37 recommendations, with the rationale behind each of them, the corresponding recommendations and guidance from other societies, when existing and the level of evidence categorized and graded according to the criteria previously endorsed by EULAR/EUVAS [2, 13]. This first draft was reviewed by all members of the CanVasc recommendation working group (using a modified Delphi method) with a phone conference held thereafter to reach consensus on all debated recommendations, especially those not agreed upon by >80 % of the reviewers. A revised version of recommendations was then developed and distributed again for review to the same working group and a broader spectrum of other reviewers, including members of several professional medical societies and specialists and the administrative bureau of the Canadian support group for vasculitis patients (Vasculitis Foundation Canada). The comments were gathered and discussed during a second teleconference with the members of the CanVasc recommendation working group to reach consensus on the final version of the document, which was endorsed by the Canadian Rheumatology Association (CRA) Guidelines Committee on March 21st, 2015.

Results

The final document (the full version of the recommendations is available online at http://www.jrheum.org) includes 19 recommendations and 17 statements addressing general management strategies for AAV, including their diagnosis, treatments with glucocorticoids, traditional immunosuppressants and biologic agents, and follow up for rheumatologists, nephrologists, respirologists, general internists, general practitioners and all other health care professionals more occasionally involved in the management of patients with AAV in community and academic practice settings. Each therapeutic recommendation and statement is accompanied by supporting text, which reports on the expected health benefits, potential side effects and risks, and Canadian system factors that may influence their applicability. Therapeutic recommendations are presented with a level of evidence and strength (Table 1 of the executive summary). Statements are for non-therapeutic recommendations and working group consensus, for which there is no strong supporting evidence from controlled studies are not graded. For each recommendation and statement, we also present in the extended version (available online with the full version of the recommendations at http://www.jrheum.org) corresponding recommendations and guidance previously published on the same topic from other societies, when available.

Table 1 Summary table of the CanVasc recommendations and statements
Full size table

Discussion and conclusion

This document will serve as useful knowledge to support decision-making for any physician involved in the care of patients with AAV, including adults and children. Best clinical judgment must however always prevail when confronted with each specific patient scenario. New information from ongoing research may already have become available by the time the present document is published. Regular updates will thus be mandatory.