Lack of association between serum immunoreactivity and Chlamydia pneumoniae detection in the human aortic wall

Background-Only a few studies have focused the attention on the relation between elevated anti-Chlamydia pneumoniae (CP) antibodies and the detection of CP in the arterial wall. The aim of our study is thus to investigate the relationship between immune response to CP and detection of CP in the aortic walls of patients with abdominal aortic aneurysm. Methods and Results-A specimen of aortic wall was obtained from 102 consecutive patients who underwent abdominal aneurysm repair. The possible presence of CP was studied by polymerase chain reaction and confirmed by nonradioactive DNA hybridization. Antibody response to CP was studied (IgG, IgA titers). We found 33 patients (32.4%) with CP DNA+. No correlation between CP DNA detection and antibody titers was found (IgG P=0.52, IgA P=0.66). High correlation between IgG and IgA titer was observed (P<0.01). Endovascular presence of CP and antibody titers was not related to the age of the patient. Conclusions-CP antibody titers are not associated with the presence of CP in the aortic wall of patients with abdominal aortic aneurysm.