Background: Churg-Strauss syndrome (CSS) is a rare systemic vasculitis associated with asthma, eosinophilia, sinusitis, and pulmonary infiltrates. CSS has been reported in association with asthma therapies.
Materials and methods: The objective is to describe the characteristics of CSS in patients treated with the anti-IgE antibody omalizumab (Xolair; Genentech Inc; South San Francisco, CA). A retrospective review of available data to identify cases of CSS was performed using the Novartis Argus global drug safety database for omalizumab in asthma patients.
Results: We identified 34 potential cases of CSS. Of these, 13 cases fulfilled at least four of the six criteria identified in the American College of Rheumatology classification criteria. Eight of the patients in these 13 definite or probable cases (62%) had CSS symptoms prior to receiving omalizumab or described symptom onset just after corticosteroid weaning. Six of the 13 patients (46%) were confirmed as having been treated with corticosteroids for what was perceived to be severe asthma; when corticosteroids were tapered in conjunction with omalizumab treatment, CSS symptoms appeared just after the tapering. There were 4 other cases of possible CSS, and the remaining 17 patients were judged to not have CSS.
Conclusions: CSS may develop in patients receiving asthma medications who have an underlying eosinophilic disorder that is unmasked by the withdrawal of therapy with corticosteroids, or in patients who delay therapy in favor of other medications. Omalizumab treatment may unmask CSS due to the weaning of corticosteroids in some asthma patients or may delay corticosteroid treatment allowing for CSS to manifest.
Trial registration: ClinicalTrials.gov Identifier: NCT00252135.