RT Journal Article SR Electronic T1 Chlamydia pneumoniae immunoglobulin A reactivation and airway inflammation in acute asthma JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 834 OP 840 DO 10.1183/09031936.02.00192002 VO 20 IS 4 A1 P.A.B. Wark A1 S.L. Johnston A1 J.L. Simpson A1 M.J. Hensley A1 P.G. Gibson YR 2002 UL http://erj.ersjournals.com/content/20/4/834.abstract AB Infection with Chlamydia pneumoniae can trigger acute asthma and is associated with severe chronic asthma. The aim of the present study was to examine the relationship between airway inflammation and serological response to C. pneumoniae in acute severe asthma. Subjects (n=54) were recruited within 4 h of presentation to the emergency department with an acute exacerbation of asthma. Clinical history taking, sputum induction (0.9% saline), spirometry and acute and convalescent serology for C. pneumoniae immunoglobulins A and G were performed. At presentation, 47% of subjects had antibodies directed against C. pneumoniae, and 38% (20) demonstrated an increase in C. pneumoniae antibody levels, with 15 demonstrating a rise in immunoglobulin A concentration. C. pneumoniae responders exhibited significantly higher sputum neutrophil levels (4.6×106 cells·mL−1) compared to nonresponders (1.2×106 cells·mL−1, p=0.02) and elevated sputum eosinophil cationic protein concentration (3,981 versus 1,122 ng·mL−1, p=0.02). An acute antibody response to Chlamydia pneumoniae is common in exacerbations of asthma. The serological features suggest that Chlamydia pneumoniae reactivation may trigger neutrophilic airway inflammation in acute asthma. This study was supported by the National Health and Medical Research Council, Canberra, New South Wales, Australia.