Acute-phase proteins and Chlamydia pneumoniae infection: which one is more important in acute coronary syndrome?

The global prevalence of Chlamydia pneumoniae, Helicobacter pylori, Cytomegalovirus and Herpes simplex virus in patients with coronary artery disease: A systematic review and meta-analysis

BACKGROUND AND AIM

Coronary Artery Disease (CAD) is one of the most important causes of death worldwide. The aim of this study was to determine the prevalence of C. pneumoniae, H. pylori, Cytomegalovirus (CMV) and Herpes simplex virus (HSV) in CAD patients based on published serological and molecular studies.

METHODS

A systematic literature search was conducted in Medline (via PubMed), Embase, Scopus and Web of Science databases (1996-2019). Both molecular and serological studies were analyzed using STATA software (Version 14).

RESULTS

145 studies were included for final analysis. We gathered and investigated the prevalence of C. pneumoniae (25.1% [95% confidence interval (CI) 21.5-28.8%]), H. pylori (12.8% [(95% CI) 4.0-22.0%]), CMV (64.4% [(95% CI) 57.7-73.0%]) and HSV (31.8% [(95% CI) 21.5-42.2%]) in CAD patients from the analysis of molecular studies. Additionally, in serological studies, the prevalence of mentioned pathogens were 72.7% [(95% CI) 67.8-77.6%], 63.3% [(95% CI) 60.0-66.5%], 62.2% [(95% CI) 58.0-66.3%] and 34.3% [(95% CI) 23.6-45.1%] respectively.

CONCLUSION

Interestingly, there was only a significant increase in the prevalence of C. pneumoniae and H. pylori in serological studies compared to the reported data from molecular studies, while the prevalence of CMV and HSV were the same in both types of studies.

Differential identification of atypical pneumonia pathogens in aorta and internal mammary artery related to ankle brachial index and walking distance

BACKGROUND

We studied the existence of agents in aorta biopsies, such as Chlamydia pneumoniae, cytomegalovirus, and Mycoplasma pneumoniae, that are thought to have a role in atherosclerosis etiopathogenesis role, and their association with peripheral artery disease.

MATERIALS AND METHODS

We examined aorta wall and internal mammarian artery (IMA) biopsies taken from two different places in 63 patients in whom coronary artery bypass was performed. In these biopsies, we evaluated the deoxyribonuclease (DNA) of these microorganisms using polymerase chain reaction. From the same patients, we recorded the ankle brachial index, road walking distance information, lipid profile, C-reactive proteins, blood parameters such as fibrinogen, and the patient's operation data.

RESULTS

In the nine aorta biopsies taken from 63 patients, we isolated C pneumoniae DNA. In IMA biopsies taken from the same patients, we detected no microorganism DNA (P < 0.001). In the same aorta biopsies, we found no cytomegalovirus or M pneumoniae DNA. We examined 12 patients using an index value of 0.9 in the ankle brachial index evaluation; eight had C pneumoniae in the aorta biopsies (P < 0.001).

CONCLUSIONS

We found a significant relationship between C pneumoniae DNA and the existence of peripheral artery disease. In the development of atherosclerosis with C pneumoniae, there may be a determinant pathogen in both the aorta and the peripheral arteries. The nonexistence of C pneumoniae DNA in the IMA biopsies may indicate infectious agents because of the predominant endothelial functions in this artery, and thus its resistance to atherosclerosis.

Association between hepatitis C virus core protein and carotid atherosclerosis

A link between certain infectious microorganisms and an increased risk of atherosclerotic disease has been suggested. By analyzing the data of subjects who had undergone general health-screening tests, a possible association between carotid atherosclerosis and seropositivity of antibody against hepatitis C virus (HCV) has been previously reported. In the present study, a possible link between carotid atherosclerosis and HCV core protein positivity was assessed, because it is postulated to be a better marker of viremia and thus persistent infection. Of the 1992 enrolled subjects, 496 (25%) had carotid artery plaque, and 25 (1.3%) were positive for HCV core protein. Carotid artery plaque was positive in 480/1967 (24%) and 16/25 (64%) of the core protein-negative and core protein-positive subjects, respectively (p<0.0001 by chi(2) test). Serum concentrations of transaminases were higher in core protein-positive subjects, but albumin concentrations were not significantly different between the 2 groups. Multivariate logistic regression analysis showed that HCV core protein positivity is an independent predictor of carotid plaque with an odds ratio of 5.61 (95% confidence interval 2.06-15.26, p<0.001). These data further support the possible link between persistent HCV infection and carotid atherosclerosis in the subjects without severe liver dysfunction.

Prevalence of Helicobacter pylori infection and its link to coronary risk factors in Japanese patients with acute myocardial infarction

The association between Helicobacter pylori (H. pylori) infection and coronary artery disease, as well as the association between H. pylori infection and classic coronary risk factors, is controversial in patients from Western countries. The high prevalence of H. pylori infection in Japanese subjects enables an examination of these associations in a large population, especially in young patients, because coronary risk factors may be more strongly associated with younger individuals than with older individuals. The IgG seropositivity to H. pylori was assessed in 618 cases with acute myocardial infarction (AMI) and in 967 controls. The prevalence of seropositivity to H. pylori was similar between cases and controls, but in subjects younger than 55 years, the rate was significantly higher in cases than in controls (58.7% vs 43.3%, p = 0.009). After adjustment for age, gender, diabetes mellitus, hypertension, smoking, body mass index, total cholesterol, and high density lipoprotein cholesterol, the odds ratio for acute myocardial infarction was 2.97 (95% confidence interval, 1.37-6.41; p = 0.006). Worsening of classic coronary risk factors was not associated with H. pylori infection in subjects younger than 55 years. These results suggest that in younger individuals in Japan, H. pylori infection is significantly associated with AMI independent of the classic coronary risk factors.

Higher C-reactive protein concentration and white blood cell count in subjects with more coronary risk factors and/or lower physical fitness among apparently healthy Japanese

Of 2,722 people (1.876 men, mean age: 51.3+/-10.3 years; 846 women, mean age: 51.4+/-11.1) who underwent the fitness check program at Aichi Prefectural Center for Health Care, the concentration of C-reactive protein (CRP) and the white blood cell count (WBC) were investigated in relation to the number of coronary risk factors, maximum oxygen uptake (VO2max) quartiles and physical fitness score. CRP was measured by conventional latex immunoturbidimetric assay. Both CRP and WBC were higher in those who had more risk factors. In men the lowest mean CRP was 0.07 mg/dl in those with only one risk factor (RF1) and the highest was 0.29 mg/dl in RF6 (p<0.0001). The lowest mean WBC was 4,868/mm3 in RF1 and the highest was 7,096/mm3 in RF6 (p<0.0001). In women the lowest mean CRP was 0.073 mg/dl in those with no risk factors (RF0) and the highest was 0.22mg/dl in RF5 (p=0.0379). The lowest mean WBC was 5,065/mm3 in RF1, and the highest was 6,792/mm3 in RF4 (p=0.0001). A similar relationship was noticed when the groups were analyzed by VO2max quartile or fitness score. CRP and WBC both showed a stepwise increase or decrease in men, but was generally in order in women in accordance with the number of risk factors, VO2max level or fitness score. In apparently healthy Japanese subjects, elevated inflammatory indices (ie, higher CRP and WBC) were associated with more coronary risk factors and poorer physical fitness. Therefore, high-risk coronary subjects might be screened by conventional measurement of CRP.