Increased frequency of Chlamydia pneumoniae antibodies in patients with asthma.

Gencay M,      Rudiger JJ,      Tamm M,      Soler M,      Perruchoud AP,      Roth M     

Antibodies, Bacterial
Asthma
Chlamydophila Infections
Chlamydophila pneumoniae
Adult
Aged
Case-Control Studies
Chronic Disease

Female
Fluorescent Antibody Technique
Human
IgA
IgG
Male
Middle Age
Support, Non-U.S. Gov't

Abstract
The worldwide increase in asthma incidences and the impact of the disease on public health care have led to new investigations of the cause of the disease.  Besides well-defined environmental causes, accumulating evidence suggests that respiratory tract infections play an important role in the pathogenesis of asthma.  Among these microorganisms Chlamydia pneumoniae is an intracellular pathogen causing persistent infection.  Chlamydia pneumoniae infection has been discussed as possibly inducing the development of asthma.  This study was designed to investigate the presence of C. pneumoniae-specific IgG, IgA, and IgM antibodies in serum samples of 33 adults with a clinical history of asthma, positive methacholine test, and reduced FEV(1).  Patients with asthma were compared with age-, sex-, and locality-matched control subjects (n = 33).  We observed no acute infection either in patients with asthma or in control subjects, but 63% of all investigated individuals had signs of past infection.  Chlamydia pneumoniae-specific IgA was detected in 52% of the patients with asthma and in 15% of the healthy control subjects (p < 0.01).  Serological evidence of chronic infection with C. pneumoniae (high IgG [> pr = 1:512] and high IgA [> or = 1:40]) was more frequent in patients with asthma (18.2%) compared with control subjects (3.0%) (p < 0.01).  Our results provide further evidence that chronic infection with C. pneumoniae is linked to asthma.

Department of Virology
Haartman Institute
University of Helsinki
Helsinki
Finland.