Mannose-binding lectin as a risk factor for acute coronary syndromes.

BACKGROUND: Mannose-binding lectin (MBL) is a multifunctional protein involved in innate immunity. We tested whether MBL and elevated viral and bacterial antibodies were risk factors for acute coronary events. DESIGN: Controlled cohort study. METHODS: A total of 354 patients with unstable angina pectoris (UA) or acute myocardial infarction (AMI) were compared with 334 paired controls. RESULTS: Enterovirus titres were associated with increased risk of UA (odds ratio 10.04, P<0.001) and AMI (odds ratio 3.18, P=0.003), but titres did not correlate with either MBL concentration or genotype. Chlamydia pneumoniae heat shock protein 60 IgG concentrations were also associated with increased risk of UA (odds ratio 1.63, P=0.049). Compared to asymptomatic controls, patients had lower complement C3 serum concentrations (P<0.001), higher MBL serum concentration, and more frequently had MBL genotypes that determined high MBL levels (P<0.001). High MBL genotypes had odds ratios of 1.16 (P=0.010) for UA and 1.12 (P=0.007) for AMI. The elevation of MBL concentrations in the acute phase correlated with MBL concentrations after recovery (r=0.85, P<0.001). CONCLUSIONS: Elevated microbial titres, indicating an on-going inflammation, were associated with cardiovascular events. MBL might have a dual role both decreasing susceptibility to infections and increasing the risk of acute coronary syndromes.

Serum chlamydial lipopolysaccharide as a prognostic factor for a new cardiovascular event.

BACKGROUND: Infections caused by Chlamydia pneumoniae are considered to participate in inflammatory processes leading to coronary artery disease. After a primary infection, the bacteria remain dormant intracellularly causing a chronic inflammatory stimulus. MATERIALS AND METHODS: Blood samples were obtained from 235 patients with acute myocardial infarction (AMI) and 108 patients with unstable angina pectoris (UA). We evaluated the prognostic significance of bacterial and viral antibody titers, serum troponin T, C-reactive protein, and chlamydial lipopolysaccharide (cLPS) concentrations during acute coronary syndrome of patients with AMI and UA for cardiovascular death and new UA and AMI that required hospital care during a 6-year follow-up. RESULTS: Serum cLPS levels correlated with C-reactive protein and serum troponin T concentrations during acute coronary events. Patients with AMI had significantly higher serum concentration of cLPS compared with patients with UA. Enterovirus antibody titers and cholesterol-lowering therapy at admission of the index event were negatively correlated with cLPS concentration (r = -.198, P = .0003 and r = -.26, P = .019, respectively). The presence of circulating cLPS was associated with a hazard ratio of 2.04 for a new cardiovascular event during the follow-up period (P = .006). The area under the curve in the receiver operating graph was .572. CONCLUSION: cLPS is evidently liberated from the infected atherosclerotic tissue during an acute coronary event. Our study supports the view that inflammation caused by C. pneumoniae infection is an important but as yet poorly understood factor in the development of atherosclerosis and may play a role in acute vascular events.

CagA antigen of Helicobacter pylori and coronary instability: insight from a clinico-pathological study and a meta-analysis of 4241 cases.

BACKGROUND: Cytotoxin-associated gene-A (CagA) antigen is expressed by some virulent strains of Helicobacter pylori (H. pylori). The role of CagA antigen in coronary instability is unknown. We performed a clinico-pathological study and a meta-analysis in the attempt to shed new light on this complex issue. METHODS: In the clinico-pathological study, 38 patients with unstable angina (UA), 25 patients with stable angina (SA), 21 patients with normal coronary arteries (NCA) and 50 age and sex matched healthy volunteers were enrolled. Serology for CagA was assessed in all patients. Specimens of atherosclerotic plaques were obtained from all patients by directional coronary atherectomy, and prepared for immunohistochemistry using anti-CagA monoclonal antibodies. The meta-analysis includes 9 studies assessing the association between seropositivity to CagA strains and acute coronary events. RESULTS: The titre of anti-CagA antibodies was significantly higher in patients with unstable angina (161+/-90 RU/ml) compared to those with stable angina (83+/-59 RU/ml p<0.02), NCA (47.3+/-29 RU/ml p<0.01) and healthy controls (73+/-69 p<0.02). Anti-CagA antibodies recognized antigens localized inside coronary atherosclerotic plaques in all specimens from both stable and unstable patients. In the meta-analysis, seropositivity to CagA was significantly associated with the occurrence of acute coronary events with an odds ratio (OR) of 1.34 (95% CI, 1.15-1.58, p=0.0003). CONCLUSIONS: Taken together these findings suggest that in a subset of patients with unstable angina, an intense immune response against CagA-positive H. pylori strains might be critical to precipitate coronary instability mediated by antigen mimicry between CagA antigen and a protein contained in coronary atherosclerotic plaques.

Periodontal destruction is associated with coronary artery disease and periodontal infection with acute coronary syndrome.

BACKGROUND: Coronary artery disease (CAD) is a highly prevalent disease with significant morbidity and mortality. Periodontal disease has been suggested to influence this disease and has been associated with CAD in some epidemiologic studies. However, this relation is still controversial. This study aimed to determine the relationship between periodontal disease measures and CAD and acute coronary syndromes (ACSs). METHODS: Two hundred one patients presenting with stable angina or ACS referred for coronary angiography underwent a periodontal assessment including evaluation of periodontal pathogens. Severity of CAD was determined by the number of obstructed coronary arteries. RESULTS: Patients with severe CAD defined by multiple vessel disease had significantly more periodontal destruction than those with mild CAD, as shown by mean clinical attachment level, a measure of chronic periodontal disease (CAL; 5.43 +/- 1.8 versus 4.85 +/- 1.6; P = 0.02), percentage of teeth with CAL >or=5 mm (82.1 +/- 23.4 versus 70.4 +/- 26.9; P = 0.002), and number of missing teeth (8.75 +/- 6.6 versus 6.76 +/- 6.6; P = 0.03). Logistic regression analysis showed that percentage of teeth with CAL >or=5 mm was significantly associated with CAD severity. Patients with ACS had significantly higher plaque scores, gingival index, and Porphyromonas gingivalis counts than stable patients. Logistic regression analysis showed that either plaque score or percentage of P. gingivalis was significantly associated with ACS. CONCLUSION: Periodontal destruction measures are significantly correlated with CAD severity, whereas periodontal infectious measures are significantly associated with clinical cardiac status.

Is Helicobacter pylori infection a risk factor for acute coronary syndromes?

OBJECTIVES: To elucidate risk factors for acute coronary syndromes (ACS), the present study examined whether Helicobacter pylori infection is a risk factor for patients with ACS. METHODS: We studied 33 male patients with acute coronary syndromes (ACS). All patients were incidence cases of ACS that they did not have a past history of IHD and were at the first onset of ACS. A control group was consisted of 66 males. Controls were at random selected from outpatients. All controls had normal resting electrocardiogram and had no history of IHD. H. pylori seropositivity was determined by an IgG-specific enzyme linked immunosorbent assay (ELISA). We serologically confirmed the presence of antibodies specific to the antigen CagA of H. pylori, using CagA ELISA. RESULTS: Seropositive rate of IgG antibodies in patients with ACS was 87.9%. A rate of in controls was 66.7%. After adjustment for age, a statistically significant association was found in H. pylori seropositivity between ACS and controls (OR, 3.74; 95% CI, 1.15-12.13). This relation was also significant after adjusted for potential confounding factors (OR, 4.09; 95% CI, 1.10-15.17). Anti-CagA positive H. pylori were significantly recognized in ACS (adjusted OR, 3.58; 95% CI, 1.08-11.82). However, this significant association was disappeared after adjusted for potential confounding factors (P=0.054). CONCLUSIONS: We confirmed a significant link between H. pylori infection and ACS. H. pylori infection is likely to be a risk factor for ACS.

Presence of Chlamydia pneumoniae DNA in the artery wall--biomarker of coronary artery disease.

Many authors have shown an association between Chlamydia pneumoniae (CPn) infection and coronary artery disease (CAD). However, whether CPn infection demonstrated by CPn DNA presence in the artery wall plays an important role in pathogenesis of CAD and acute coronary events (i.e. unstable angina) remains to be elucidated. One hundred and fifteen consecutive patients with CAD (51 with unstable angina and 64 with stable angina) were compared with 52 control subjects with aortic valve disease without angiographic evidence of CAD. The presence of CPn DNA in the aortic wall was assessed with nested polymerase chain reaction (PCR), and the IgM, IgG and IgA anti-CPn titres were assessed with microimmunofluorescence test. CPn DNA presence in the artery (i.e. aortic) wall was associated with 3.7-fold increased risk of CAD (95% CI 1.2-11.3, P < 0.01); however, no statistically significant difference in CPn DNA presence was demonstrated between unstable and stable angina (17.6% vs. 25%). In the CPn DNA positive group more often than in the CPn DNA negative group, serological signs of chronic infection (55.2% vs. 27%, P = 0.004) were demonstrated, whereas no statistically significant differences were demonstrated in prevalence of either acute infection (9.3% vs. 0%) or reinfection (0% vs. 0%). In conclusion, CPn DNA presence in the artery (i.e. aortic) wall was associated with CAD, therefore may be used as a biomarker for CAD. Moreover, no statistically significant differences in CPn DNA presence in the artery wall and in serology were present between unstable and stable angina; therefore, CPn infection does not seem implicated in triggering an acute coronary event.

Effects of antibiotic therapy on outcomes of patients with coronary artery disease: a meta-analysis of randomized controlled trials.

CONTEXT: Although Chlamydia pneumoniae infection has been associated with the initiation and progression of atherosclerosis, results of clinical trials investigating antichlamydial antibiotics as adjuncts to standard therapy in patients with coronary artery disease (CAD) have been inconsistent. OBJECTIVE: To conduct a meta-analysis of clinical trials of antichlamydial antibiotic therapy in patients with CAD. DATA SOURCES: The MEDLINE and Cochrane Central Register of Controlled Trials databases were searched from 1966 to April 2005 for English-language trials of antibiotic therapy in patients with CAD. Bibliographies of retrieved articles were searched for further studies. Presentations at major scientific meetings (2003-2004) were also reviewed. Search terms included antibacterial agents, myocardial infarction, unstable angina, and coronary arteriosclerosis. STUDY SELECTION: Eligible studies were prospective, randomized, placebo-controlled trials of antichlamydial antibiotic therapy in patients with CAD that reported all-cause mortality, myocardial infarction, or unstable angina. Of the 110 potentially relevant articles identified, 11 reports enrolling 19,217 patients were included. DATA EXTRACTION: Included studies were reviewed to determine the number of patients randomized, mean duration of follow-up, and end points. End points of interest included all-cause mortality, myocardial infarction (MI), and a combined end point of MI and unstable angina. DATA SYNTHESIS: Event rates were combined using a random-effects model. Antibiotic therapy had no impact on all-cause mortality among treated vs untreated patients (4.7% vs 4.6%; odds ratio [OR], 1.02; 95% confidence interval [CI], 0.89-1.16; P = .83), on the rates of MI (5.0% vs 5.4%; OR, 0.92; 95% CI, 0.81-1.04; P = .19), or on the combined end point of MI and unstable angina (9.2% vs 9.6%; OR, 0.91; 95% CI, 0.76-1.07; P = .25). CONCLUSION: Evidence available to date does not demonstrate an overall benefit of antibiotic therapy in reducing mortality or cardiovascular events in patients with CAD.

[Previous infection with Chlamydia pneumoniae and long-term prognosis in patients with acute coronary syndrome with non-ST segment elevation]. / Infección previa por Chlamydia pneumoniae y pronóstico a largo plazo en pacientes con síndrome coronario agudo sin elevación del segmento ST.

BACKGROUND AND OBJECTIVE: Contradictory data exists from case-control studies and in patients with stable coronary artery disease on the association of prior exposure to Chlamydia pneumoniae and cardiovascular events. We underwent a prospective study to investigate the prognostic value of C. pneumoniae seropositivity in patients with acute coronary syndromes. PATIENTS AND METHOD: In a prospective cohort of 259 consecutive patients (194 men and 65 women), mean age 65 (10 years) with non-ST elevation acute coronary syndromes, we measured serum levels of IgG antibodies directed against C. pneumoniae. RESULTS: After a mean follow-up of 28 (25, 29) months, the incidence of cardiovascular death or myocardial infarction was of 15% in seropositive patients versus 13% in seronegatives at IgG titers (1:64 (p=0.58); of 14% versus 14% at IgG titers > or = 1:128 (p=0.96); and of 14% versus 15% at IgG titers (1:256 (p=0.82). The relative risks (RR, 95% CI) of these major cardiac events adjusted for possible confounding factors were 1.11 (0.52-2.40); 1.01 (0.52-1.96); and 0.94 (0.48-1.87) respectively. CONCLUSIONS: Chlamydia pneumoniae IgG seropositivity is not associated with a higher incidence of death or myocardial infarction in patients with non-ST segment elevation acute coronary syndromes.

Association of peripheral mononuclear cells containing Chlamydia pneumoniae DNA with acute coronary syndrome and stable coronary artery disease in Japanese subjects.

To clarify the association of Chlamydia pneumoniae DNA in peripheral blood mononuclear cells (PBMCs) with acute coronary syndrome (ACS) and stable coronary artery disease (CAD) in Japanese adults, touchdown-nested polymerase chain reaction was used to detect the presence of C. pneumoniae DNA. The prevalence of C. pneumoniae DNA in PBMCs was similar in a comparison of 88 patients (52.3%) with ACS, 164 patients (50.0%) with stable CAD, and 88 control subjects (50.0%). Temporal changes in the prevalence of C. pneumoniae DNA in PBMCs were also assessed every 3 months during a 1-year period (n=59). The prevalence was significantly higher in the first 3-month period (January through March) than in any of the other 3-month periods. In conclusion, the prevalence of C. pneumoniae DNA in PBMCs in patients with ACS or stable CAD was comparable to that in control populations. Furthermore, the presence of circulating C. pneumoniae was strongly associated with seasonal variability.

Chlamydia pneumoniae infection is associated with coronary artery disease but not implicated in inducing plaque instability.

BACKGROUND: Many authors have shown an association between Chlamydia pneumoniae (C. pneumoniae) infection and coronary artery disease. However, whether C. pneumoniae infection plays an important role in triggering an acute coronary event remains to be elucidated. METHODS: Sixty-four consecutive patients with unstable angina (group A), 56 consecutive patients with stable exertional angina (group B) and 74 control subjects (group C) were studied. The IgM, IgG and IgA anti-C. pneumoniae titers were assessed (microimmunofluorescence test Labsystem), values > or =1:16, > or =1:32 and > or =1:16 being respectively considered positive. RESULTS: IgM antibodies were found in 10.9% of group A and 12.5% of group B patients, whereas no subject of group C showed IgM titers (A vs. B, p=ns; C vs. A and B, p<0.05). Positive IgG titers were found in 76.6%, 82% and 44.6% in groups A, B and C, respectively (A vs. B, p=ns; C vs. A and B, p<0.05). Positive IgA titers were found in 62.5%, 61% and 31.1% in groups A, B and C, respectively (A vs. B, p=ns; C vs. A and B, p<0.05). Acute infection was observed in 10.9% and 12.5% of patients in groups A and B, respectively (p=ns); reinfection in 17% and 11%; no patient of the control group had signs of acute infection or reinfection. Chronic infection was observed in 34.4% and 37.5% in group A and B, respectively (p=ns). CONCLUSION: C. pneumoniae infection is associated with coronary artery disease, but no difference in serology is present between unstable and stable angina. Therefore, it does not seem implicated in triggering an acute coronary event.

Seroprevalence of IgG antibodies to Chlamydia pneumoniae and Helicobacter pylori among coronary heart disease patients and normal individuals in South Indian population.

In recent years, the role of infectious agents in the aetiology of atherosclerotic disease has come to the forefront. In the present study, seroprevalence (IgG) of chlamydia pneumoniae and helicobacter pylori in patients with atherosclerotic coronary heart disease was compared to normal healthy adults. Out of a total of 117 patients 101 had unstable angina (UA) and 16 had chronic stable angina (CSA). C. pneumoniae seropositivity was found in 66% of patients with UA and 94% of CSA patients. The corresponding figures for H. pylori were 58% and 56% respectively. In comparison, 81% of healthy adults were seropositive for C. pneumoniae and 53% for H.pylori. No significant association was found between CHD and the infectious agents. However, this study has revealed a high infection by C. pneumoniae as well as H.pylori in this part of India.

[Heat shock protein antibodies and other chlamydial antigens in various diseases and their occurrence in blood donors]. / Protilátky proti proteinu tepelného soku a dalsím antigenum chlamydií u nekterých chorob ve srovnání s jejich výskytem u dárcu krve.

BACKGROUND: The chlamydial infections are very frequently considered in the causal connection with some diseases e.g. atherosclerosis or chronic joint infections. The evidence of the antibodies against the heat shock protein of chlamydial origin is not the usual part of practical serological diagnostics. The aim of this study is an attempt to identify antibodies against the heat shock protein and other antigens of chlamydiae in the sera of two groups of patients and in the sera of blood donors. METHODS AND RESULTS: The sera of patients suffering from unstable angina pectoris (NAP = 69), sera of patients waiting for the application of endoprothesis due to coxarthrosis (EKK = 49), and sera of 100 blood donors have been examined for antibodies against the heat shock protein, against the major outer membrane protein (MOMP) of C. pneumoniae, and against the chlamydial genus specific lipolysaccharides. The antibodies against the cHSP60 in the sera of patients suffering from NAP have been identified in 41 cases (59.4%), in orthopaedic patients in 21 cases (42.9%) and in 23 of the blood donors (23%). The difference of the antibody-occurrence in the sera of patients is significantly higher than in case of blood donors. The antibodies against the MOMP of C. pneumoniae prevailed in all sera of the persons examined. Their occurrence in the IgG class had a high statistical frequency. The genus specific positive reaction occurred more frequently also in the sera of the probands that reacted positively against the cHSP60 than in those negatively reacting. According to our results, the significance of C. pneumoniae in the genesis of the antibodies against of cHSP60 can be concluded. CONCLUSIONS: The proof of the anti-cHSP60 antibody and of the species-specific chlamydial antibodies may be a useful contribution to the exact diagnosis of the disease with possible chlamydial participation. The C. pneumoniae infection was probably of the main importance for the origin of the anti-cHSP60 antibody in examined persons.

[Serologic study of atherosclerosis and its vascular complications]. / Sérologické vysetrení u aterosklerózy a jejich cévních komplikací.

Chlamydia pneumoniae (C. p.) is very frequently cited as an important factor of the origin of atherosclerosis. To confirm the diagnostic value of the serological examination the following reactions have been used: microimmunofluorescence reaction (MIF) for estimating of antibodies against major outer membrane proteins C. p. (anti-MOMP) and ELISA for detecting antibodies against the lipopolysacharides of C. p. (anti-LPS), both in IgA and IgG immunoglobulin classes of the serum. The ELISA for the detection of the IgG antibodies against chlamydial heat shock protein (cHSP60) has been used. The sera of 155 patients suffering from acute myocardial infarction (AMI) and 69 patients with unstable angina pectoris (UAP) have been examined. The heart disease has been confirmed by anamnesis, electrocardiography and coronarography. As a control group the sera from 112 persons without sings of a heart disease were examined. The antibodies against the cHSP60 have been determined only in the sera 69 patients with UAP and 49 control sera. Statistically higher occurrence of the antibodies anti-MOMP C. p. in the IgA class sera of patients suffering from UAP has been noted compared with those found in the sera of the control group (chi 2 = 18.56; p < 0.01). In the globulin IgG class of the both groups no difference has been found. The anti-LPS C. p. antibodies in the IgA as well in IgG anti-LPS classes of the patients sera with UAP were present significantly more frequently than in the control group (chi 2 = 11.49; p < 0.01, chi 2 = 4.16; p < 0.05). Similarly the incidence of the anti-LPS C. p. antibodies in the IgA class sera of 155 patients suffering from AMI was significantly higher than in the control group (chi 2 = 8.55; p < 0.01). The anti-cHSP60 antibodies have been found in 41 out of 69 patients suffering from UAP (59.4%) and in 21 of 49 control individuals (42.9%). The results seem to confirm an important role of C. p. in atherogenesis. The monitoring of the antibodies against the C. p. may supplement the diagnostics in patients suffering from UAP and AMI and the efficacy of its therapy and prevention as well.

Chlamydia pneumoniae in the atherosclerotic plaques of patients with unstable angina undergoing coronary artery bypass grafting: does it have prognostic implications?

OBJECTIVE: This study sought to evaluate the prognostic significance of the presence of DNA of Chlamydia pneumoniae in the coronary atherosclerotic lesions of patients with unstable angina. BACKGROUND: C. pneumoniae has been implicated in the pathogenesis of coronary artery disease by serological and pathological studies, but whether antichlamydial antibodies and the presence of this pathogen in the coronary atherosclerotic tissue are related to prognosis in unstable angina remains unclear. METHODS: A total 76 coronary specimens from 45 patients with unstable angina undergoing bypass surgery were subjected to nested polymerase chain reaction (PCR) for C. pneumoniae. Antichlamydial immunoglobulin G (IgG), A (IgA) and M (IgM) were also examined by an enzyme immunoassay. Patients were followed during a 2-year period to determine the incidence of adverse cardiovascular events. RESULTS: DNA of C. pneumoniae was detected in 57 (75%) of 76 atherosclerotic lesions: 39 patients showed a positive PCR result in at least one plaque. Of the 45 patients, 44 (97.7%) showed a positive serological result: IgG was positive in 39 (86.6%) patients, IgM in five (11.1%) patients and IgA in 42 (93.3%). Clinical characteristics and serologic results were similarly distributed in patients with and without infected lesions at enrollment. At least one adverse event occurred in 21 (46.6%) of the 45 patients at 2 years: death in nine (20%), recurrent angina in 12 (26.6%), revascularization in six (13.3%) and myocardial infarction in two (4.4%) patients. The composite endpoint of death, myocardial infarction, recurrent angina and revascularization at 2-year follow-up did not differ according to the PCR or serologic results. CONCLUSIONS: The presence of C. pneumoniae in coronary atherosclerotic plaques of patients with unstable angina undergoing coronary bypass grafting does not have prognostic significance. In addition, serology does not allow us to differentiate those patients with plaque infection by C. pneumoniae and also does not provide any prognostic information in these patients.

[Occurrence of chlamydia infection in relation to lipidemia indicators in the etiology of unstable angina pectoris]. / Ucast chlamydiové infekce ve vztahu k ukazatelum lipémie v etiologii nestabilní anginy pectoris (NAP).

The presence of Chlamydia pneumoniae infection was examined in 66 patients with unstable angina pectoris (UAP), 155 patients with acute myocardial infarction (AIM) and 112 controls without signs of a heart disease. Besides evaluation of anamnestic data, ECG and coronarographic examination, serologic examination of C. pneumoniae by the microfluorescent method anti-MOMP and ELISA of anti-LPS of globulin IgA and IgG serum classes in every patient was performed. Moreover, in patients with UAP, routine biochemical methods for the detection of total cholesterol levels and its lipoprotein fractions LDL, HDL and triacylglycerols were used. The levels of anti-MOMP C. pneumoniae antibodies and anti-LPS of the IgA class in sera of patients with UAP were statistically highly significantly increased (chi 2 = 19.54; chi 2 = 12.92; p < 0.01) and anti-LPS of the IgG class significantly increased (chi 2 = 6.15; p < 0.05) in comparison with controls. It can be assumed that the participation of C. pneumoniae is aetiologically possible. Total cholesterol levels, LDL, HDL and triacylgylcerols were increased above the normal range in 34.8%, 48.5%, 39.4% and 28.8% of patients, respectively. The anti-LPS C. pneumoniae ELISA test of globulin class IgA in patients with UAP seems to be the most suitable method for the determination of infections with C. pneumoniae.

Serological markers of Chlamydia pneumoniae, cytomegalovirus and Helicobacter pylori infection in diabetic and non-diabetic patients with unstable angina pectoris.

The possible role of inflammation in coronary artery disease (CAD) is being recognised, while markers of inflammation (e.g., CRP) and infection with Chlamydia pneumoniae (C. pneumoniae), cytomegalovirus (CMV) and Helicobacter pylori (H. pylori) have been proposed as risk factors for CAD. However, these associations require further evaluation. It is a known fact that diabetic patients suffer from impaired immune response to some pathogens and a high incidence of atherosclerosis. In this case-control study we investigated serological markers of infection with C. pneumoniae, CMV, and H. pylori in a group of 140 patients with unstable angina pectoris (UA), 52 of them having type 2 diabetes mellitus, and in a matched control group. Anamnestic (IgG) and acute infection (IgA) antibodies against the above agents were tested using ELISA or indirect immunofluorescence tests. In patients with UA we found a significantly higher seroprevalence and titres of IgG antibodies against C. pneumoniae (p = 0.04) and increased titres of IgG antibodies against CMV (p = 0.007). No differences were found in IgA antibody response to these pathogens. Antibody response to H. pylori was similar in both groups tested. In diabetic patients with UA, the frequency of group-common IgG antibodies against C. pneumoniae was higher than in the non-diabetic UA patients. The other serological markers studied were comparable in the patients with or without diabetes mellitus. Our findings confirmed association of C. pneumoniae and CMV with cardiovascular heart disease. Moreover, diabetes mellitus may predispose the patients to C. pneumoniae infection. However, serological markers observed do not indicate that destabilisation of angina pectoris is associated with acute C. pneumoniae or CMV infection. No relationship was found between UA and H. pylori infection.

Prevalence of Chlamydia pneumoniae in the atherosclerotic plaque of patients with unstable angina and its relation with serology.

BACKGROUND: Chlamydia pneumoniae has been associated with coronary artery disease by both seroepidemiological studies, and by direct detection of the micro-organism in atherosclerotic lesions. This bacteria could play a potential role in the development of acute coronary events. We examined coronary arteries from patients with unstable angina in order to verify an endovascular presence of C. pneumoniae, and to determine if there is any relationship between serology of acute infection by this pathogen and its presence inside the atherosclerotic plaque of these patients. METHODS: We analysed a total of 76 atherosclerotic plaques obtained from 45 patients who underwent coronary artery bypass surgery. In all patients unstable angina was present within the prior 3 weeks. The presence of C. pneumoniae in the plaque was determined by nested polymerase chain reaction (PCR). Antichlamydial immunoglobulin G (IgG), A (IgA) and M (IgM) was examined by microimmunofluorescence and compared to the PCR result. FINDINGS: DNA of C. pneumoniae was detected in 57 (75%) of 76 atherosclerotic lesions. In most cases (74/76: 97%) a positive IgA, IgM or IgG result was seen. Seven (12%) and 54 (94%) of the 57 PCR positive plaques came from patients with a positive IgM and IgA result, respectively. There was no statistical significant difference between PCR positive and PCR negative plaques in patients with a positive or negative serological result. Clinical characteristics were similarly distributed in patients with and without infected lesions. INTERPRETATION: C. pneumoniae organisms are frequently found in the atherosclerotic lesions of patients undergoing coronary surgery for unstable angina. Neither serological results of acute or recent infection by C. pneumoniae nor clinical characteristics are useful in predicting the individual risk of harbouring C. pneumoniae in the coronary lesions of patients with unstable angina.

Combined role of the Lewis antigenic system, Chlamydia pneumoniae, and C-reactive protein in unstable angina.

OBJECTIVES: The goal of this study was to assess the prognostic role of the Lewis antigenic system, Chlamydia pneumoniae (CP) seropositivity (CP+), and C-reactive protein (CRP) levels in unstable angina (UA). BACKGROUND: The role of CP infection in acute coronary syndromes is contradictory. The Lewis antigenic system, a genetically determined blood group system associated with infections and several disorders, including ischemic heart disease, might influence the susceptibility to CP infection, inflammatory response, and risk of cardiac ischemic events. METHODS: The CRP levels, Lewis antigens, and CP+ were measured in 54 patients with Braunwald's class IIIB UA. All patients were followed up for one year, and the occurrence of new coronary events (coronary death, myocardial infarction, and recurrence of instability) were recorded. RESULTS: Twenty-five coronary events occurred during follow-up. At univariate analysis CRP >3 mg/l (CRP+) (p = 0.0056), Lewis antigen b (Leb+) (p = 0.028), and the combination of Leb+ and CP+ (p = 0.006) and of CRP+ and Leb+ (p = 0.003) were associated with new coronary events, while CP+ alone was not. At multivariate analysis, CRP+ (p = 0.008) and combined Leb+CP+ (p = 0.03) were independent predictors of worse outcome. The event rate was 64% in CRP+ patients, 67% in Leb+CP+ patients, and 86% in CRP+Leb+CP+ patients. Combined Leb+CP+, but not Leb+ and CP+ alone, was related to CRP levels (p = 0.03). Among CP+ patients, CRP levels were higher in Leb+ than Leb- (p = 0.028). CONCLUSIONS: Our data demonstrate that in UA the Lewis antigenic system plays an important role, probably determining individual susceptibility to the detrimental effects of CP infection and by determining an enhanced inflammatory response.

Helicobacter pylori seropositivity in patients with unstable angina.

AIM: The pathogenesis of ischemic heart diseases has been correlated, on epidemiological and pathogenetic grounds, with infections by viruses and bacteria, including Helicobacter pylori (H. pylori). THE AIM: of this study were to investigate the association of unstable angina (UA) with anti-H. pylori seropositivity in a case-control study and to search for the classic cardiovascular risk factors in both infected and uninfected patients. METHODS: We studied 32 consecutive patients (20 males, 12 females), mean age 65 years (range 42-89), with final diagnosis of UA. A total of 64 subjects (40 males, 24 females, mean age 65 years, range 42-89) admitted to the Emergency Care Unit, age and sex-matched, served as controls. The presence of hypertension, serum levels of cholesterol and glucose, plasma levels of fibrinogen, smoking habit and social class were investigated in all patients. Cases and controls were inhabitants of NorthWestern Italy, and had similar socioeconomic status as based on working place and on instruction level. H. pylori seroprevalence was assessed by the presence of antibodies (IgG) against H. pylori by means of a commercial enzyme immunosorbent assay. RESULTS: Antibodies to H. pylori were found in 26/32 (81%) of the patients and in 34/64 (53%) of the controls (p=0.007); the odds ratio was 3.82 (95% confidence interval 1.27 to 12.04). Classical cardiovascular risk factors, such as socio-economic status, did not differ among patients with and without antibodies to H. pylori. CONCLUSION: Patients with unstable angina had a significantly higher seroprevalence of anti-H. pylori than the control population. Classical risk factors for ischemic heart disease, such as the indicators of socio-economic status, were equally distributed among infected or uninfected patients with UA.