Chlamydia Pneumoniae antibody titers and cardiac calcifications: A cross-sectional serological-echocardiographic correlative study

Background: Chlamydia pneumoniae has previously been associated with higher prevalence of valvular and cardiac calcifications. Objectives: To investigate a possible association of seropositivity for C. pneumoniae and the presence of cardiac calcifications (mitral annular or aortic root calcification, and aortic valve sclerosis). Methods: We retrospectively analyzed serological data (immunoglobulin G TWAR antibodies) from the AZACS trial (Azithromycin in Acute Coronary Syndromes), and correlated the serological findings according to titer levels with the presence of cardiac calcifications as detected by transthoracic echocardiography. Results: In 271 patients, age 69 ± 13 years, who underwent both serological and echocardiographic evaluation, we found no significant association between the "calcification sum score" (on a scale of 0-3) in seropositive compared to seronegative patients (1.56 ± 1.15 vs. 1.35 ± 1.15, respectively, P= 0.26). The median calcification sum score was 1 (interquartile range 0-3) for the seronegative group, and 2 (interquartile range 0-3) for the seropositive group (P = 0.2757). In addition, we did not find a significant correlation of any of the individual sites of cardiac calcification and C. pneumoniae seropositivity. Conclusion: Our findings suggest that past C. pneumoniae infection may not be associated with the pathogenesis of valvular and cardiac calcifications.