Background: Little is known about the long-term outcome of airflow obstruction in asthma of patients with Churg-Strauss syndrome (CSS).
Methods: We conducted a retrospective study of 24 consecutive patients (aged 41.1 +/- 13.5 years) with CSS in a single center. All had asthma (starting 8.1 +/- 9.5 years prior to the diagnosis of CSS), blood eosinophilia (6.1 +/- 4.4 x 10(9)/l) and systemic manifestations of CSS. Antineutrophil cytoplasmic antibodies were found in 7 of 22 tested patients. Seven patients had smoked (a mean of 10 pack-years). All patients received oral corticosteroids, 11 cyclophosphamide and 23 inhaled corticosteroids.
Results: Airflow obstruction was found in 14 patients (70%) at diagnosis, and in 11 of 22 patients (50%) at the time of the clinical remission of CSS. The mean postbronchodilator FEV1/FVC and FEV1 were 69 +/- 12% and 74 +/- 21% of predicted at diagnosis (n = 20); 71 +/- 10% and 92 +/- 19% of predicted at the clinical remission (n = 22); and 64 +/- 13% and 80 +/- 21% at last visit (n = 13), respectively. During follow-up, postbronchodilator FEV1 increased by 30 +/- 28% in six patients with FEV1/FVC < 70% despite inhaled therapy who received higher dose of oral corticosteroids. At last visit, 5 of 13 patients (38%) with more than 3 years of follow-up had persistent airflow obstruction as defined by postbronchodilator FEV1/FVC < 70% and FEV1 < 80% of predicted.
Conclusion: Airflow obstruction due to uncontrolled asthma is present despite corticosteroids in many patients at diagnosis and at clinical remission of CSS, and during follow-up. It may be still partly reversible with increased oral corticosteroid treatment.