Background: There is growing evidence linking infection with Chlamydophila pneumoniae with vascular diseases, such as atherosclerosis and myocardial infarction. However, the data remain inconclusive and the clinical importance of C. pneumoniae as vasculopathic is unclear. So, we intend to detect C. pneumoniae in acute myocardial infarction patients by microimmunofluorescence (mIF) and polymerase chain reaction (PCR).

Methods:Blood and peripheral mononuclear cells (PMNCs) of 24 myocardial infarction patients and 100 normal controls were collected. Serum were used in mIF and PMNCs in PCR. PMNC sample were tested for C. pneumoniae by ‘touchdown’nested PCR. The first round PCR amplified DNA from both C. pneumoniae and Chlamydophila psittaci, while the second round specially targeted C. pneumoniae allowing the two species to be differentiated.

Results: Seropositivity of IgG and IgM anti-Chlamydophila pneumoniae antibody titers were 95.8% and 25% in myocardial infarction patients and 61% and 16% in control group, respectively. Positive rates of PCR of PMNCs were 8.3% in the patients and 15% in control group.

Conclusion:The results of mIF show that mIF positive rate in myocardial infarction was much higher than control group. So an association between C. pneumoniae and myocardial infarction can be concluded. But the opposite results of PCR of PMNCs needed further studies. (Korean J Clin Microbiol 2003;6(1):81-87)