Immunofluorescence in situ and the serologic indices of Chlamydia pneumoniae infection in patients with an abdominal aortic aneurysm.

The aim of the study was to evaluate the frequency of Chlamydia pneumoniae infection in patients with abdominal aortic aneurysm (AAA) using selected methods. The histological specimens of aneurysm wall were evaluated, the method of immunofluorescence was used to reveal the antigen in the wall of AAA and the titers of specific antibodies of IgG, IgM and IgA classes in blood plasma were marked. Atherosclerotic changes in the aneurysm wall were found in all patients. In 20(87%) patients the C. pneumoniae antigen was seen in the wall of abdominal aneurysm using the indirect immunofluorescence method. A significant relation between the method of direct C. pneumoniae diagnosis, aneurysm symptoms and histologically detected inflammation in its wall was confirmed. Serologic markers of the chronic C. pneumoniae infection were seen in 20(87%) out of 23 patients and in 6(30%) out of 20 subjects of the control group and this difference was statistically significant. It was observed, that all patients with serologic indices of active C. pneumoniae infection, had symptomatic aneurysm. The presence of Chlamydia pneumoniae in the wall of AAA as well as the occurrence of serologic indices of the chronic infection in these patients can confirm the hypothesis of the relation between the infection with this microorganism and the development of the disease.