Objectives: to investigate the presence of Chlamydia pneumoniae in the wall
of abdominal aortic aneurysms (AAAs) and in the aortas of patients without
a history of cardiovascular disease.
Design: case-control study.
Materials: twenty-six consecutive patients operated for AAA were compared t
o 17 controls.
Methods: aorta was obtained at surgery or autopsy (controls) and prepared f
or immunohistochemical (IHC) analysis and culture for C.pneumoniae. Throat
swabs from 14/26 patients were analysed by PCR for C. pneumoniae. Blood was
obtained from 24/26 patients and from 178 70-year-old males.
Results: C. pneumoniae was detected in the aortic aneurysms of 20/26 patien
ts by IHC. C. pneumoniae was cultured from 10 of the 20 IHC-positive patien
ts. Only 1/17 controls was positive for C. pneumoniae by IHC (p = 0.0001).
PCR was positive for C. pneumoniae in 5/14 patients. Serological analysis b
y microimmunofluoresence (MIF) showed significantly more high titres of the
specific antibodies to C. pneumoniae in patients than in age-matched male
controls.
Conclusions: we conclude that C. pneumoniae is often present in AAAs in a v
iable form and that C. pneumoniae is linked to the pathogenesis of AAA.