Churg-Strauss syndrome: evidence for disease subtypes?
OBJECTIVE
Churg-Strauss syndrome (CSS) is a rare systemic small-vessel necrotizing vasculitis. Its main clinical characteristics, some potentially life-threatening, are now well known, as are its usual successive phases, from allergic rhinitis to asthma, and finally vasculitis. Conversely, physiopathogenetic mechanisms are not completely elucidated and clearly multiple, thereby suggesting the existence of different disease subtypes.


RESULTS
Almost 40% of CSS patients have circulating antineutrophil cytoplasm autoantibodies (ANCAs), mostly directed against myeloperoxidase. ANCA-positive patients suffer more frequently from renal disease, peripheral nervous system involvement and/or alveolar hemorrhage, whereas frequent cardiac involvement, lung infiltrates and/or systemic manifestations are more common in those who are ANCA-negative. However, their respective global outcomes do not clearly differ. Patients might also be categorized according to other, more subtle clinical, radiological and/or biological parameters, for example, cardiac magnetic resonance imaging abnormalities or genetic background.


CONCLUSIONS
Because of its practical and therapeutic repercussions, the priority remains the prompt, relatively easy identification of the most severely affected patients at CSS diagnosis, before searching for and trying to classify subsets. Large, collaborative studies are needed to determine whether other subgroups might be associated with outcomes and warrant different, and possibly new, therapeutic strategies.
Department of Internal Medicine, French Vasculitis Study Group, National Referral Center for Necrotizing Vasculitides and Systemic Scleroderma, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, Université Paris-Descartes, Paris, France. christian.pagnoux@cch.aphp.fr
Christian
C
Pagnoux
Loïc
L
Guillevin
D019268:Antibodies, Antineutrophil Cytoplasmic / Q000378:metabolism*; D015551:Autoimmunity / Q000235:genetics / Q000502:physiology; D015415:Biomarkers; D015267:Churg-Strauss Syndrome / Q000145:classification* / Q000175:diagnosis / Q000503:physiopathology*; D018450:Disease Progression; D042241:Early Diagnosis; D006801:Humans; D017063:Outcome Assessment, Health Care / Q000592:standards; D009195:Peroxidase / Q000276:immunology
D019268:Antibodies, Antineutrophil Cytoplasmic; D015415:Biomarkers; D009195:Peroxidase