Chlamydia pneumoniae DNA in peripheral venous blood samples from patients with carotid artery stenosis

In the study presented here, peripheral blood specimens obtained from patients with atherosclerosis were examined for the presence of Chlamydia pneumoniae to determine whether these specimens can be used for routine testing. Chlamydia pneumoniae DNA was detected in 7 of 56 patients with carotid stenosis and in three of four patients with other atherosclerotic diseases, but it was not detected in any of 50 healthy controls or in any of 59 age- and gender-matched patients suffering from other nonatheroselerotic diseases. IgG antibodies indicative of an active Chlamydia pneumoniae infection were detected by microimmunofluorescence in two of nine PCR-positive patients but in none of 41 PCR-negative patients. Four of nine serum samples obtained from PCR-positive patients contained IgA antibodies compared to 5 of 41 samples obtained from PCR-negative patients. plaques by polymerase chain reaction (PCR), immunohistochemistry, electron microscopy, and cell culture [2, 3]. Although serology was useful in the initial demonstration of this association, further studies showed that MEF serology is of only limited value in determining an individual patient's risk for harboring Chlamydia pneumoniae in atherosclerotic vessels [4]. Since it is not usually possible to examine specimens from atherosclerotic plaques as a routine diagnostic procedure, a need exists for alternative detection methods using samples that can be obtained more easily, such as serum or blood specimens. Therefore, the present study was conducted using peripheral venous blood specimens and serum samples from patients with atherosclerosis to test for the presence of Chlamydia pneumoniae DNA and antibodies.