Churg-Strauss syndrome, also known as eosinophilic granulomatosis with polyangiitis, is a rare disorder that causes inflammation of the blood vessels, which can restrict blood flow to vital organs and tissue and cause permanent damage. Patients may have a variety of symptoms, such as asthma, gastrointestinal bleeding, pain, and rashes, which can significantly reduce their quality of life.
Long-term outcomes in patients with Churg-Strauss have not been well defined, but a European study recently published in Arthritis Care & Research provides new insights on the impact of this condition and patient and disease characteristics that can affect morbidity and the risk of relapse.1
The study included 101 patients (58 women and 43 men) who fulfilled the American College of Rheumatology criteria for Churg-Strauss and were treated for the condition from January 1990 through December 2011 at 1 of 3 tertiary centers in the United Kingdom (n = 60; 59.4%), France (n = 23; 22.8%), or Italy (n = 18; 17.8%). The mean age at diagnosis was 50 years (range, 17-80 years).
Of the study patients, 57 (56.4%) were antineutrophil cytoplasm autoantibody (ANCA)-negative, 43 (42.6%) were ANCA-positive, and 1 had unknown ANCA status. ANCA-positive patients were moqre often ≥65 years (P = .01) and men (P = .0001).
High Yield Clinical Pearls
- ANCA positivity may be predictive of renal and neurological involvement in Churg-Strauss
- In this study, the rate of cardiomyopathy did not differ according to ANCA status
Contrary to previous studies suggesting increased cardiac involvement with ANCA-negative disease,2 the researchers found that the rate of cardiomyopathy did not differ according to ANCA status, suggesting cardiac eosinophil infiltration is the more important pathogenic mechanism.
However, patients with ANCA-positive disease were more likely to have neurological (P = .0004) and renal involvement (P =.02) and subsequent complications, including chronic neurologic disability (P =.02) and chronic kidney disease (P =.03).
“Neurologic damage is particularly important to patients in view of the long-term disability impact on function, neuropathic pain, and quality of life, despite no impact on survival,” the authors wrote.
Overall, disease-related complications were prevalent, affecting 83.2% of patients. Those who had ear, nose, or throat (ENT) involvement, however, were less likely to have renal (P = .04) and cardiac (P = .03) morbidity, suggesting ENT manifestations were protective.
During the study, most patients (79.6%) achieved a first remission, but the majority (81.1%) relapsed. The only factor associated with a higher relapse-free survival was being Italian, with these patients having 64% less chance of relapse than their British counterparts, independent of their age, sex, ANCA status, and ENT status (P = .01). The lower risk of relapse in Italian patients was attributed to later corticosteroid tapering and longer use of immunosuppressive drugs in these patients.
After a median follow-up of 6 years, the overall mortality rate was low at 6.9%. Of the 7 patients who died, 5 were ANCA-positive and 2 were ANCA negative The mortality rate was 8.7% among the French group (n = 2), 8.3% among the British group (n = 5), and 0% in the Italian group. No factor was significantly associated with mortality, but patients older than 65 years with cardiomyopathy or ANCA positivity were more likely to have serious outcomes.
Summary and Clinical Applicability
The study findings suggest that patients with Churg-Strauss have good overall mortality rates but an unacceptably high rate of morbidity and relapse. ANCA positivity might be predictive of renal and neurological involvement and complications, whereas ENT involvement might be a good prognostic factor.
Based on their findings, the authors suggest that the challenges of managing Churg-Strauss revolve around preventing morbidity and improving quality of life, which might be facilitated by prolonging use of low-dose corticosteroids and immunosuppressive drugs.
Limitations and Disclosures
The study is limited by its observational and retrospective design.
1. Durel CA, Berthiller J, Caboni S, Jayne D, Ninet J, Hot A. Long-term follow-up of a multicenter cohort of 101 patients with eosinophilic granulomatosis with polyangiitis (Churg-Strauss). Arthritis Care Res (Hoboken). 2016;68(3):374-387.
2. Mukhtyar C, Flossmann O, Hellmich B, et al; European Vasculitis Study Group (EUVAS). Outcomes from studies of antineutrophil cytoplasm antibody associated vasculitis: a systematic review by the European League Against Rheumatism systemic vasculitis task force. Ann Rheum Dis. 2008;67(7):1004-1010.