C-reactive protein levels and viable Chlamydia pneumoniae in carotid artery atherosclerosis

Carotid artery stenosis and inflammatory biomarkers: the role of inflammation-induced immunological responses affecting the vascular systems

The death, disability and economic cost of stroke are enormous. Indeed, among the 16 million people worldwide who suffer a stroke' annually, nearly six million die, and another five million are left permanently disabled making prevention of stroke one of the most important priorities in healthcare. Currently carotid artery stenosis (CS) or narrowing of the common carotid artery (CCA) or internal carotid artery (ICA) due to atherosclerotic plaque, accounts for 20-30% of all ischemic strokes. Atherosclerosis is now regarded as a chronic inflammatory disease in response to vascular compromise especially from hypertension. This has long been known to lead to inflammation and atherosclerotic plaque formation in the blood vessels. This mini-review aims to highlight the role of inflammation and neuro-immunological processes in carotid artery disease. Various cellular elements of inflammation and advanced imaging techniques have been identified as potential markers of plaque progression. Therapies related to decreasing and modulating immune-responsive inflammation in the carotid vessels have been shown to translate into decreased occurrence of acute neurologic events and improvement of clinical outcomes.

C-reactive protein as a marker of persistent Chlamydia trachomatis infection is not associated with tubal factor infertility-an independent clinical validation study

STUDY QUESTION

Does C-reactive protein (CRP), as a marker of persisting low-grade inflammation, identify Chlamydia trachomatis IgG antibody test (CAT)-positive women who are at the highest risk for tubal factor infertility (TFI)?

SUMMARY ANSWER

No association was found between slightly elevated CRP (seCRP) levels and TFI in our CAT-positive patient population.

WHAT IS KNOWN ALREADY

In the fertility work-up, CAT is used to estimate the risk for TFI and to select high-risk patients for additional invasive diagnostic procedures (e.g. hysterosalpingography and laparoscopy). However, a high number of false positives exist among CAT-positive patients. In a previous study, it has been suggested that women with TFI may be identified more accurately when combining CAT with CRP, a marker for persistent low-grade inflammation.

STUDY DESIGN, SIZE, DURATION

Our original retrospective cohort consisted of 887 consecutive female patients who visited the fertility clinic of a tertiary care centre between 2007 and 2015. All CAT-positive women who underwent laparoscopy (as the reference test for evaluation of tubal function) and who had not undergone previous pelvic surgery were included in the study. CRP was determined in spare serum samples, and medical data was obtained by chart review.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 101 women (11.4%) were CAT-positive, and 64 of these 101 women (7.2%) met all inclusion criteria. CAT was performed with an ELISA. TFI was assessed by laparoscopy and strictly defined as extensive peri-adnexal adhesions and/or distal occlusion of at least one tube. In spare sera, CRP was performed with a high-sensitivity CRP ELISA, and CRP levels between 3 and 10 mg/L were defined as positive. Analyses were corrected for BMI, endometriosis and smoking.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no statistically significant association between seCRP level and TFI after adjusting for BMI, endometriosis and smoking (odds ratio 1.0; 95% CI 0.3–3.3; n = 64).

LIMITATIONS, REASONS FOR CAUTION

Our retrospective study had a small sample size due to a low CAT-positivity rate and a conservative clinical policy with regard to invasive diagnostic testing. Additionally, CRP levels were only measured once, while they may change throughout the menstrual cycle and in time.

WIDER IMPLICATIONS OF THE FINDINGS

Contrary to previous findings, our results show CRP is not suitable as a marker of persistent low-grade inflammation in CAT-positive women. Other inflammatory markers and immunogenetic host factors should be studied on their clinical validity and utility to improve non-invasive risk assessment for TFI in the fertility work-up.

STUDY FUNDING/COMPETING INTEREST(S)

This work was partially supported by the European EuroTrans-Bio Grant [Reference number 110012 ETB] and the Eurostars grant (E!9372). S.A.M., a full-time employee of Amsterdam University Medical Centres location VUMC (0.56 fte) and the Maastricht University Medical Center (0.44 fte), is the founder (2011) and CEO of TubaScan Ltd, a spin-off company, Dept. of Medical Microbiology and Infection Prevention, Amsterdam UMC, location VUmc, Amsterdam, the Netherlands. S.O. and E.F.v.E. at the time of conducting this research had a partial appointment at TubaScan Ltd.

Association of Chlamydia trachomatis, C. pneumoniae, and IL-6 and IL-8 Gene Alterations With Heart Diseases

Atherosclerosis is a progressive disease characterized by chronic inflammation of the arterial walls, associated with genetic and infectious factors. The present study investigated the involvement of Chlamydia trachomatis and Chlamydia pneumoniae infections and immunological markers (C-reactive protein, CRP, TNF-α, IL-6, IL-8, and IL-10) in the process of atherosclerosis. The evaluation included 159 patients for surgical revascularization (CAD) and 71 patients for surgical heart valve disease (HVD) at three hospitals in Belém, Brazil. The control group (CG) comprised 300 healthy individuals. Blood samples collected before surgery were used for antibodies detection (enzyme immunoassay), CRP (immunoturbidimetry) and IL-6 levels (enzyme immunoassay). Tissue fragments (atheroma plaque, heart valve and ascending aorta) were collected during surgery and subjected to qPCR for detection of bacterial DNA. Promoter region polymorphisms of each marker and relative quantification of TNF-α, IL-8, and IL-10 gene expression were performed. Demography and social information were similar to the general population involved with both diseases. Antibody prevalence to C. trachomatis was 30.6, 20.3, and 36.7% (in the CAD, HVD, and CG, respectively) and to C. pneumoniae was 83.6, 84.5, and 80.3% (in the CAD, HVD, and CG, respectively). C. trachomatis cryptic plasmid DNA was detected in 7.4% of the samples. Frequency of IL6−174G>C polymorphism was higher in CAD and HVD than in CG regardless of previous exposure to Chlamydia. Previous C. trachomatis infection showed involvement in HVD and CAD. Significant association between disease and previous C. pneumoniae infection was found only among HVD. GG genotype of IL6−174G>C is apparently a risk factor for heart disease, whereas AT genotype of IL8−251A>T was mainly involved in valvulopathies, including patients with prior exposure to C. pneumoniae.

Neck vein obstruction: Diagnosis and the role of chronic persistent Chlamydophila pneumoniae infection

Background

The objective of this review is to describe the diagnosis of neck vein obstruction and the possible role of chronic persistent Chlamydophila pneumoniae infection in producing the syndrome of chronic cerebrospinal venous obstruction.

Method

The normal patterns of flow in the neck veins are described and guidelines for interpretation of the quantitative duplex ultrasound examination of the extracranial neck veins are developed.

Result

An infective cause of neck vein obstruction is proposed and from a literature search of the role of the obligate intracellular bacterium Chlamydophila pneumoniae in vascular and chronic diseases, a diagnostic protocol for confirming chronic persistent Chlamydophila pneumoniae infection, which includes the quantitative duplex ultrasound examination and specific blood tests are suggested.

Conclusion

Further research to validate this diagnostic protocol is required.

Investigation of Chlamydia pneumoniae infection in Moroccan patients suffering from cardiovascular diseases

Chlamydia pneumoniae is an intracellular bacterium responsible for respiratory diseases and is highly involved in cardiovascular disease development, mainly atherosclerosis. The main objective of our study was to evaluate C. pneumoniae prevalence in Moroccan patients suffering from cardiovascular diseases. A total of 115 patients with cardiovascular diseases were enrolled, and their clinical and behavioral information was recorded. Blood was sampled from all patients as well as the atheroma plaques from 36 patients undergoing surgery. Nested PCR was performed for C. pneumoniae DNA detection in both peripheral blood mononuclear cells (PBMCs) and atheroma plaques. Statistical analysis was performed using EpiInfo software. Data analysis showed cardiovascular disease dominance in men, with a sex ratio M/F of 3.4, a majority of tobacco users (52.2%), and many diabetics (44.3%). A significant difference between genders was shown for tobacco use (p<0.05). Positive cases for PBMCs and atheroma plaques were 61% and 86%, respectively, and a significant difference between PBMCs and atheroma plaque infection was identified (p=0.02). Data analysis also showed that 12% of patients presented only C. pneumoniae infection as a risk factor. Therefore, the high prevalence of C. pneumoniae suggests its involvement in atherosclerosis, and further investigation is recommended for confirmation.

Role of gut microbiota in atherosclerosis

Infections have been linked to the development of cardiovascular disease and atherosclerosis. Findings from the past decade have identified microbial ecosystems residing in different habitats of the human body that contribute to metabolic and cardiovascular-related disorders. In this Review, we describe three pathways by which microbiota might affect atherogenesis. First, local or distant infections might cause a harmful inflammatory response that aggravates plaque development or triggers plaque rupture. Second, metabolism of cholesterol and lipids by gut microbiota can affect the development of atherosclerotic plaques. Third, diet and specific components that are metabolized by gut microbiota can have various effects on atherosclerosis; for example, dietary fibre is beneficial, whereas the bacterial metabolite trimethylamine-N-oxide is considered harmful. Although specific bacterial taxa have been associated with atherosclerosis, which is supported by increasing mechanistic evidence, several questions remain to be answered to understand fully how the microbiota contributes to atherosclerosis and cardiovascular disease. Such knowledge might pave the way for novel diagnostics and therapeutics based on microbiota.

C-reactive protein plays a marginal role in cognitive decline: a systematic review and meta-analysis

OBJECTIVE

The objective of the study was to investigate the association between peripheral levels of C-reactive protein (CRP) and cognitive decline that is defined by 2-5 years of cognitive change in general cognitive function or specific cognitive domain.

METHODS

We searched PubMed and Google for prospective/longitudinal studies that report the association between peripheral levels of CRP and risk of cognitive decline in the nondementia population.

RESULTS

Out of 479 related articles from PubMed and Google, four studies with a total of 5255 non-demented subjects that report odds ratio (OR)/relative risk/hazard ratio of CRP levels and decline in general cognition met our criteria for meta-analysis. The association between higher levels of CRP and risk of global cognitive decline was weak but significant (OR, 1.27 [95% CI, 1.02 to 1.58]). However, the systematic review from six other articles that were not suitable for meta-analysis revealed a marginal association between CRP and cognitive decline in certain domains.

CONCLUSION

Our analysis demonstrated a weak association between peripheral CRP level and global cognitive decline. Because of the small number of included studies and varied methodologies that they applied, caution should be taken when generalizing our finding to the full range of cognitive changes in different cognitive domains observed in non-demented people.

The cytokines within the carotid plaque in symptomatic patients with internal carotid artery stenosis

Materials and methods

The experiment was carried out on 100 symptomatic patients with internal carotid artery stenosis that underwent carotid endarterectomy. Every patient had the wall of the carotid artery resected during organ harvesting surgery in order to evaluate some cytokines (TGF-β, VEGF, FGF, TNF-α) and to perform the immunohistochemistry (IHC). An immunoreactive score (IRS) was calculated based on the staining intensity and the number of cells stained. Over a 3-year period, 7 patients died, and 2 patients were lost to follow-up. The study group consisted of 91 patients. The control group comprised 20 young organ donors with confirmed death brain, who had their normal carotid artery sampled.

Results

In all healthy donors (control group) with normal carotid arteries the three cytokines (TGF-β, VEGF, TNF-α) were not discovered. The presence of FGF was confirmed in 25% of healthy donors, probably due to an intima fibroblasts activity, responsible for the synthesis of elastin and collagen to the extracellular matrix (ECM). Only three cytokines (TGF-β, FGF, TNF-α) were found within atheromatous plaques (study group).

Conclusions

Our research confirmed that these factors may accelerate the development of atheromatic plaque and its destabilisation.

The aim of the study was the evaluation of the inflammatory cytokines within atheromatic carotid plaque.

Electronic supplementary material

The online version of this article (doi:10.1186/1749-8090-9-139) contains supplementary material, which is available to authorized users.

Long-term follow-up of unruptured intracranial aneurysms repaired in California

Object

Using a database that enabled longitudinal follow-up, the authors assessed the long-term outcomes of unruptured cerebral aneurysms repaired by clipping or coiling.

Methods

An observational analysis of the California Office of Statewide Health Planning and Development (OSHPD) database, which follows patients longitudinally in time and through multiple hospitalizations, was performed for all patients initially treated for an unruptured cerebral aneurysm in the period from 1998 to 2005 and with follow-up data through 2009.

Results

Nine hundred forty-four cases (36.5%) were treated with endovascular coiling, 1565 cases (60.5%) were surgically clipped, and 76 cases were treated with both coiling and clipping. There was no significant difference in any demographic variable between the two treatment groups except for age (median: 55 years for the clipped group, 58 years for the coiled group, p < 0.001). Perioperative (30-day) mortality was 1.1% in patients with coiled aneurysms compared with 2.3% in those with clipped aneurysms (p = 0.048). The median follow-up was 7 years (range 4–12 years). At the last follow-up, 153 patients (16.2%) in the coiled group had died compared with 244 (15.6%) in the clipped group (p = 0.693). The adjusted hazard ratio for death at the long-term follow-up was 1.14 (95% CI 0.9–1.4, p = 0.282) for patients with endovascularly treated aneurysms. The incidence of intracranial hemorrhage was similar in the two treatment groups (5.9% clipped vs 4.8% coiled, p = 0.276). One hundred ninety-three patients (20.4%) with coiled aneurysms underwent additional hospitalizations for aneurysm repair procedures compared with only 136 patients (8.7%) with clipped aneurysms (p < 0.001). Cumulative hospital costs per patient for admissions involving aneurysm repair procedures were greater in the clipped group (median cost $98,260 vs $81,620, p < 0.001) through the follow-up.

Conclusions

For unruptured cerebral aneurysms, an observed perioperative survival advantage for endovascular coiling relative to that for surgical clipping was lost on long-term follow-up, according to data from an administrative database of patients who were not randomly allocated to treatment type. A cost advantage of endovascular treatment was maintained even though endovascularly treated patients were more likely to undergo subsequent hospitalizations for additional aneurysm repair procedures. Rates of aneurysm rupture following treatment were similar in the two groups.

Investigating the association between influenza vaccination and reduced stroke risk

Acute infections, mainly of the respiratory tract, have consistently been demonstrated to considerably increase the risk of stroke. At present, prospective interventional trials are lacking and there is no proof of the effectiveness of any therapeutic anti-infective strategy in stroke prevention. However, some new evidence from observational studies lends support to the idea that influenza vaccination may contribute importantly to fighting stroke. Although final proof of efficacy is still missing, patients with previous cerebral ischemia and subjects of any age at high risk of stroke should be encouraged to receive annual influenza vaccination.

Plasmacytoid dendritic cells mediate the regulation of inflammatory type T cell response for optimal immunity against respiratory Chlamydia pneumoniae infection

Chlamydia pneumoniae (Cpn) infection is a leading cause for a variety of respiratory diseases and has been implicated in the pathogenesis of chronic inflammatory diseases. The regulatory mechanisms in host defense against Cpn infection are less understood. In this study, we investigated the role of plasmacytoid dendritic cells (pDCs) in immune regulation in Cpn respiratory tract infection. We found that in vivo depletion of pDCs increased the severity of infection and lung pathology. Mice depleted of pDC had greater body weight loss, higher lung bacterial burden and excessive tissue inflammation compared to the control mice. Analysis of specific T cell cytokine production pattern in the lung following Cpn infection revealed that pDC depleted mice produced significantly higher amounts of inflammatory cytokines, especially TNF-α, but lower IL-10 compared to the controls. In particular, pDC depleted mice showed pathogenic T cell responses characterized by inflammatory type-1 (CD8 and CD4) and inflammatory Th2 cell responses. Moreover, pDC depletion dramatically reduced CD4 regulatory T cells (Tregs) in the lungs and draining lymph nodes. Furthermore, pDC-T cell co-culture experiments showed that pDCs isolated from Cpn infected mice were potent in inducing IL-10 producing CD4 Tregs. Together, these findings provide in vivo evidence for a critical role of pDCs in homeostatic regulation of immunity during Cpn infection. Our findings highlight the importance of a ‘balanced’ immune response for host protective immunity and preventing detrimental immunopathology during microbial infections.

Impact of viral and bacterial infections in coronary artery disease patients

Atherosclerosis is becoming an alarming disease for the existence of healthy human beings in the 21^st century. There are a growing number of agents, either modernized life style generated, competitive work culture related or infection with some bacterial or viral agents, documented every year. These infectious agents do not have proper diagnostics or detection availability in many poor and developing countries. Hence, as active medical researchers, we summarize some aspects of infectious agents and their related mechanisms in this review which may be beneficial for new beginners in this field and update awareness in the field of cardiovascular biology.

Unchanged safety outcomes in deep brain stimulation surgery for Parkinson disease despite a decentralization of care

OBJECT

Early work on deep brain stimulation (DBS) surgery, when procedures were mostly carried out in a small number of high-volume centers, demonstrated a relationship between surgical volume and procedural safety. However, over the past decade, DBS has become more widely available in the community rather than solely at academic medical centers. The authors examined the Nationwide Inpatient Sample (NIS) to study the safety of DBS surgery for Parkinson disease (PD) in association with this change in practice patterns.

METHODS

The NIS is a stratified sample of 20% of all patient discharges from nonfederal hospitals in the United States. The authors identified patients with a primary diagnosis of PD (332.0) and a primary procedure code for implantation/replacement of intracranial neurostimulator leads (02.93) who underwent surgery between 2002 and 2009. They analyzed outcomes using univariate and hierarchical, logistic regression analyses.

RESULTS

The total number of DBS cases remained stable from 2002 through 2009. Despite older and sicker patients undergoing DBS, procedural safety (rates of non-home discharges, complications) remained stable. Patients at low-volume hospitals were virtually indistinguishable from those at high-volume hospitals, except that patients at low-volume hospitals had slightly higher comorbidity scores (0.90 vs 0.75, p < 0.01). Complications, non-home discharges, length of hospital stay, and mortality rates did not significantly differ between low- and high-volume hospitals when accounting for hospital-related variables (caseload, teaching status, location).

CONCLUSIONS

Prior investigations have demonstrated a robust volume-outcome relationship for a variety of surgical procedures. However, the present study supports safety of DBS at smaller-volume centers. Prospective studies are required to determine whether low-volume centers and higher-volume centers have similar DBS efficacy, a critical factor in determining whether DBS is comparable between centers.

The glycolipid exoantigen derived from Chlamydia muridarum activates invariant natural killer T cells

The chlamydial glycolipid exoantigen (GLXA), a glycolipid antigen derived from Chlamydia muridarum, has been implicated in chlamydial-host cell interaction. Although glycolipid antigens from Sphingomonas and related bacteria have been shown to activate invariant natural killer T (iNKT) cells, it is not yet known whether GLXA can activate these cells. In this study, we have for the first time investigated the role of GLXA in iNKT cell activation using in vitro as well as in vivo settings. First, we examined the effect of GLXA on iNKT cell activation in a cell-free antigen-presentation assay, and found that GLXA specifically stimulated iNKT1.4 hybridoma cell produce enhanced amounts of IL-2. Next, we analyzed the effect of pharmacological activation of iNKT cells by GLXA using iNKT cell-deficient (iNKT knockout (KO)) mice and bone marrow-derived dendritic cell (BMDC)-liver mononuclear cell (LMC) coculture system. On stimulation with GLXA, iNKT cells produced higher quantities of cytokines in a CD1d-dependent fashion. More importantly, iNKT cells from GLXA-treated, but not from cell mock-treated, mice showed higher expression of activation marker, CD69, and enhanced production of interferon (IFN)-γ and IL-4 in vivo. Cumulatively, these data provide evidence on the pharmacological ability of GLXA in specifically activating iNKT cells.

Management of incidentally discovered intracranial vascular abnormalities

With the widespread use of brain imaging studies, neurosurgeons have seen a marked increase in the number of incidental intracranial lesions, including vascular abnormalities. Specifically, the detection of incidentally discovered aneurysms, arteriovenous malformations, cavernous angiomas, developmental venous anomalies, and capillary telangiectasias has increased. The best management strategy for most of these lesions is controversial. Treatment options include observation, open surgery, endovascular procedures, and radiosurgery. Multiple factors should be taken into account when discussing treatment indications, including the natural history of the disease and the risk of the treatment. In this article, the authors focus on the natural history of these lesions and the risk of the treatment, and they give recommendations regarding the most appropriate management strategy based on the current evidence in the literature and their experience with intracranial vascular abnormalities.

Chlamydia pneumoniae heat shock protein 60 enhances expression of ERK, TLR-4 and IL-8 in atheromatous plaques of coronary artery disease patients

Chlamydia pneumoniae heat shock protein (cHSP) 60 is produced during chronic chlamydial infection and activate innate immune and inflammatory responses thereby contributing to atherogenesis. However, to date there is no apparent signaling cascade delineated in human atherosclerotic plaques in C. pneumoniae positive coronary artery disease (CAD) patients. Atherosclerotic plaques were obtained from 40 CAD patients (28 men, 12 women) attending Department of Cardio Thoracic and Vascular Surgery Safdarjung Hospital, New Delhi. Atherosclerotic plaques were used for gene expression studies at RNA level by real-time PCR and to study expression of ERK1/2, JNK1/2, NF-kB, IkkB and MCP-1 at protein level by immunoblotting. Significantly higher (p < 0.001) RNA expression was found for IL-8, TLR-2/4, TGF-β, ICAM1, VCAM1 and MAPKinase genes, whereas significantly lower (p < 0.001) RNA expression for SMAD4, IkkB, BRCA1 and IL-10 was detected in cHSP60-positive atheromatous plaque of CAD patients. Moreover, at proteins level pERK1/2 (p = 0.05), NF-kB (p = 0.017), MCP-1 (p = 0.011) was higher and IkkB expression was lower (p = 0.038) in cHSP60-positive atheromatous plaque of CAD patients. This study by using human atheromatous plaques at RNA and protein levels demonstrated higher expression of TLR-2/4, IL-8, ICAM1, VCAM1, ERK1/2 and NF-kB in cHSP60-positive CAD patients.

Chlamydia pneumoniae heat shock protein 60 is associated with apoptotic signaling pathway in human atheromatous plaques of coronary artery disease patients

BACKGROUND

Chlamydia pneumoniae heat shock protein (HSP) 60 is known to contribute to the activation of inflammation. In addition, there are contradictory reports on C. pneumoniae and their role in activation of pathways (apoptotic/antiapoptotic/necrosis) in coronary artery disease (CAD). Hence, more studies are required to know the actual role of C. pneumoniae in activation of apoptotic/antiapoptotic/necrosis pathways.

METHODS AND RESULTS

In this study, two sets of patient groups (cHSP60 positive and cHSP60 negative) were included and gene expression was studied by cDNA micro array and real time polymerase chain reaction arrays. Expression of Caspase-3, 8, 9, c-FLIP, PPAR-γ, PGC-1α, and Gsk-3b were also evaluated at protein level by immunoblotting. In cHSP60 positive CAD patients significantly higher (p<0.001) mRNA expression was found for CCL4, CXCL4, CXCL9, IL-8, CD40LG, CD8, TGFβ1, TGFβ2, APOE, EGR1, CTGF, APOB, LDLR, LPA, and LPL, whereas significantly lower (p<0.001) mRNA expression was detected for CD4, IL1F10, IFNA2, and IL-10 as compared to cHSP60 negative CAD patients. Additionally, at protein level expression of Caspase-3 (p=0.027), 8 (p=0.028), and 9 (p=0.037) were higher and c-FLIP (p=0.028) and PPAR-γ (p=0.95) expression were comparable in cHSP60 positive CAD patients compared to cHSP60 negative CAD patients.

CONCLUSION

Genes/proteins of pre-apoptotic caspase dependent/independent pathways, chemokines, and inflammatory cytokines receptors were significantly up-regulated in human atheromatous plaques of cHSP60 positive CAD patients suggesting an association of cHSP60 with CAD.

Geographic variation and regional trends in adoption of endovascular techniques for cerebral aneurysms

OBJECT

Considerable evolution has occurred in treatment options for cerebral aneurysms. Development of endovascular techniques has produced a significant change in the treatment of ruptured and unruptured intracranial aneurysms. Adoption of endovascular techniques and increasing numbers of patients undergoing endovascular treatment may affect health care expenditures. Geographic assessment of growth in endovascular procedures has not been assessed.

METHODS

The National Inpatient Sample (NIS) was queried for ICD-9 codes for clipping and coiling of ruptured and unruptured cerebral aneurysms from 2002 to 2008. Patients with ruptured and unruptured cerebral aneurysms were compared according to in-hospital deaths, hospital length of stay, total hospital cost, and selected procedure. Hospital costs were adjusted to bring all costs to 2008 equivalents. Regional variation over the course of the study was explored.

RESULTS

The NIS recorded 12,588 ruptured cerebral aneurysm cases (7318 clipped and 5270 coiled aneurysms) compared with 11,606 unruptured aneurysm cases (5216 clipped and 6390 coiled aneurysms), representing approximately 121,000 aneurysms treated in the study period. Linear regression analysis found that the number of patients treated endovascularly increased over time, with the total number of endovascular patients increasing from 17.28% to 57.59% for ruptured aneurysms and from 29.70% to 62.73% for unruptured aneurysms (p < 0.00001). Patient age, elective status, and comorbidities increased the likelihood of endovascular treatment (p < 0.00001, p < 0.00004, and p < 0.02, respectively). In patients presenting with subarachnoid hemorrhage (SAH), endovascular treatments were more commonly chosen in urban and academic medical centers (p = 0.009 and p = 0.05, respectively). In-hospital deaths decreased over the study period in patients with both ruptured and unruptured aneurysms (p < 0.00001); presentation with SAH remained the single greatest predictor of death (OR 38.09, p < 0.00001). Geographic analysis showed growth in endovascular techniques concentrated in eastern and western coastal states, with substantial variation in adoption of endovascular techniques (range of percentage of endovascular patients [2008] 0%-92%). There were higher costs in patients treated endovascularly, but these differences were likely secondary to presenting diagnosis and site-of-service variations.

CONCLUSIONS

The NIS database reveals a significant increase in the use of endovascular techniques, with the majority of both ruptured and unruptured aneurysms treated endovascularly by 2008. Differences in hospital costs between open and endovascular techniques are likely secondary to patient and site-of-service factors. Presentation with SAH was the primary factor affecting hospital cost and a greater percentage of endovascular procedures completed at urban academic medical centers. There is substantial regional variation in the adoption of endovascular techniques.

Behavioral equipoise: a way to resolve ethical stalemates in clinical research

Randomized trials depend on clinicians feeling that they are morally justified in allowing their patients to be randomized across treatment arms. Typically such justification rides on what has been called "clinical equipoise"--when there is disagreement of opinion among the community of experts about whether one treatment is better than another, then physicians can ethically enter their patients into a clinical trial, even if individual physicians are not at equipoise. Recent debates over prominent studies, however, illustrate that controversy can be easily created rather than dispelled by trials, with many clinicians choosing not to use the proven therapy until they receive more convincing evidence of its superiority. In such situations, we propose that a new standard of equipoise be used to guide decisions about the ethical justifications for research trials--a standard of behavioral equipoise. Under behavioral equipoise, a trial is potentially justifiable if it addresses behavioral resistance to prior scientific evidence.

Association of carotid plaque Lp-PLA(2) with macrophages and Chlamydia pneumoniae infection among patients at risk for stroke

Background

We previously showed that the burden of Chlamydia pneumoniae in carotid plaques was significantly associated with plaque interleukin (IL)-6, and serum IL-6 and C-reactive protein (CRP), suggesting that infected plaques contribute to systemic inflammatory markers in patients with stroke risk. Since lipoprotein-associated phospholipase A2 (Lp-PLA₂) mediates inflammation in atherosclerosis, we hypothesized that serum Lp-PLA₂ mass and activity levels and plaque Lp-PLA₂ may be influenced by plaque C. pneumoniae infection.

Methodology/Principal Findings

Forty-two patients underwent elective carotid endarterectomy. Tissue obtained at surgery was stained by immunohistochemistry for Lp-PLA₂ grade, macrophages, IL-6, C. pneumoniae and CD4+ and CD8+ cells. Serum Lp-PLA₂ activity and mass were measured using the colorimetric activity method (CAM™) and ELISA, respectively. Serum homocysteine levels were measured by HPLC. Eleven (26.2%) patients were symptomatic with transient ischemic attacks. There was no correlation between patient risk factors (smoking, coronary artery disease, elevated cholesterol, diabetes, obesity, hypertension and family history of genetic disorders) for atherosclerosis and serum levels or plaque grade for Lp-PLA₂. Plaque Lp-PLA₂ correlated with serum homocysteine levels (p = 0.013), plaque macrophages (p<0.01), and plaque C. pneumoniae (p<0.001), which predominantly infected macrophages, co-localizing with Lp-PLA₂.

Conclusions

The significant association of plaque Lp-PLA₂ with plaque macrophages and C. pneumoniae suggests an interactive role in accelerating inflammation in atherosclerosis. A possible mechanism for C. pneumoniae in the atherogenic process may involve infection of macrophages that induce Lp-PLA₂ production leading to upregulation of inflammatory mediators in plaque tissue. Additional in vitro and in vivo research will be needed to advance our understanding of specific C. pneumoniae and Lp-PLA₂ interactions in atherosclerosis.

Chlamydophila pneumonia: Specific mRNA in aorta ascendens in patients undergoing coronary artery by-pass grafting

The objective of this prospective study was to investigate if Chlamydophila pneumoniae (Cp)-specific DNA and mRNA are present in tissue samples from the wall of aorta ascendens in patients undergoing by-pass surgery for coronary artery disease (CAD) that includes stable angina pectoris (SAP, 25 patients) and acute coronary syndrome (ACS, 19 patients). Viable Cp was detected in 8/44 (18%) patients using reversed transcriptase PCR (RT-PCR) against bacterial mRNA with detection of cDNA using real-time PCR against the MOMP gene. Cp DNA was detected by nested PCR in 22/44 (50%) patients and by real-time PCR in 13/44 (30%) patients. In total, 24/44 (55%) patients were positive for Cp nucleic acid in any PCR. Antibodies to Cp were detected in 13/24 (54%) Cp PCR-positive and in 15/20 (75%) Cp PCR-negative patients. Nested PCR was run on throat swabs from all patients. No significant differences were noted between SAP and ACS patients regarding PCR results or serology. It has been suggested that Cp may be a 'silent passenger' picked up by the atherosclerotic plaque. Our findings of viable and metabolically active bacteria in aortic tissue add further support to the hypothesis that Cp may have an active role in the pathogenesis of atherosclerosis.

Presence of Chlamydophila pneumoniae DNA but not mRNA in stenotic aortic heart valves

BACKGROUND

The pathogenesis of aortic valve stenosis may involve inflammation and we have previously demonstrated Chlamydophila pneumoniae (C. pneumoniae) DNA in stenotic aortic heart valves. Dissemination of these bacteria is probably mediated by alveolar macrophages. Bacterial DNA alone does not indicate whether the bacteria are viable and replicating. This study aimed to investigate the presence of C. pneumoniae mRNA, a marker of replicating bacteria, and C. pneumoniae DNA in stenotic aortic valves and the prevalence of C. pneumoniae in peripheral blood mononuclear cells (PBMC).

METHODS

DNA was extracted from heart valves and PBMC and mRNA from heart valves from 76 patients undergoing aortic valve replacement surgery. C. pneumoniae DNA and mRNA were measured by real-time PCR targeting the ompA gene.

RESULTS

C. pneumoniae DNA was demonstrated in 22% of heart valves and in 5% of PBMC. C. pneumoniae mRNA was not detected in any valve. Patients positive for C. pneumoniae in the valve underwent coronary artery by-pass grafting more often (p=0.01) and suffered from angina pectoris (p=0.02) and arterial hypertension (p=0.03) more often than patients negative for C. pneumoniae in the valve.

CONCLUSIONS

These findings support a role for C. pneumoniae in the pathogenesis of aortic valve stenosis and indicate that the bacteria disseminate from the respiratory tract long before the patients were in need of surgery and that the valve infection thereafter entered into a persistent and non-replicative state. Moreover, patients positive for C. pneumoniae in the valve more often needed by-pass grafting because of more advanced coronary disease.

Treatment of unruptured intracranial aneurysms: surgery, coiling, or nothing?

The decision of whether and how to treat an unruptured intracranial aneurysm (UIA) is complex. The goal in caring for patients with UIAs is to maximize their duration of high-quality life by optimally balancing the risks of aneurysm rupture--the "natural history" of the aneurysm--with those of treatment-related adverse outcomes. In this article, we review the literature concerning the natural history of UIAs and summarize the procedure-associated morbidity and mortality and efficacy of surgical clipping and endovascular coiling. Using this information, we make recommendations regarding the optimal management of patients with UIAs.

High immunoglobulin A seropositivity for combined Chlamydia pneumoniae, Helicobacter pylori infection, and high-sensitivity C-reactive protein in coronary artery disease patients in India can serve as atherosclerotic marker

Atherosclerosis is increasingly recognized as a chronic inflammatory disease. A variety of infectious agents (Chlamydia pneumoniae, Helicobacter pylori, and cytomegalovirus [CMV]) and inflammatory marker such as high-sensitivity C-reactive protein (hs-CRP) have been found to be associated with atherosclerosis and its consequences. There is a need to know about the type and burden of infection in coronary artery disease (CAD) patients and the level of hs-CRP in India as there is growing evidence that a variety of pathogens are participating in the development and/or acceleration of at least pre-existing atherosclerosis. In addition, there is a need to find the association between these pathogens and conventional risk factors among CAD patients in India, to possibly identify a prognostic marker. In this study 192 patients with incident or prevalent CAD attending the Cardiology Outpatient Department of Safdarjung Hospital, New Delhi, India, were enrolled. In addition, 192 age-and sex-matched controls were also included. Cases and controls differ significantly in seropositivity to C. pneumoniae immunoglobulin IgA (154 vs 76) and IgG (71 vs 48) (P < 0.001, P < 0.015), H. pylori IgA (98 vs 57) and IgG (77 vs 43) (P < 0.001, P < 0.001), CMV IgG (62 vs 38) (P = 0.01) and with hs-CRP (114 vs 60) (P < 0.001), respectively. The level of hs-CRP was higher in CAD patients with IgA seropositivity of C. pneumoniae and H. pylori (5.18 and.65 mg/l) than the IgG of these bacteria (3.73 and 3.36 mg/l), respectively. These findings support an association between specific infectious agents, namely, C. pneumoniae, H. pylori, CMV, and hs-CRP in CAD patients. Association of hs-CRP with IgA specific for C. pneumoniae and H. pylori suggests the role of chronic infection in the development of CAD and may be used as a marker to target the population.

Recent trends in the treatment of cerebral aneurysms: analysis of a nationwide inpatient database

Object

The most appropriate treatment for cerebral aneurysms, both ruptured and unruptured, is currently under debate, and updated guidelines have yet to be defined. The authors attempted to identify trends in therapy for cerebral aneurysms in the US as well as outcomes.

Methods

The authors retrospectively reviewed data from the Nationwide Inpatient Sample hospital discharge database (Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality) for the period 1993–2003. Multiple variables were categorized and subjected to statistical analysis for International Classification of Diseases, 9th Revision, Clinical Modification codes related to subarachnoid hemorrhage (SAH), unruptured aneurysm, and clipping and endovascular treatment of cerebral aneurysm.

Results

During the study period, the numbers of discharges remained stable for SAH but doubled for unruptured aneurysms. Concomitantly, the number of aneurysms treated with clip placement remained stable, and the number treated by means of endovascular procedures doubled. By the study's end, the mortality rates had decreased 20% for SAH and 50% for unruptured aneurysms. Increasing age was associated with increased mortality rates, mean length of hospital stay (LOS), and mean charges (p < 0.01). Endovascular treatment was used more often in older patients (p < 0.01). Teaching status and larger hospital size were associated with higher charges and longer hospital stays (although the association was not statistically significant) and with better outcomes (p < 0.05) and lower mortality rates (p < 0.05), especially in patients who underwent aneurysm clipping (p < 0.01). Endovascular treatment was associated with significantly higher mortality rates in small hospitals (p < 0.001) and steadily increasing morbidity rates (45%). Morbidity rates, mean LOS, and mean charges were higher for aneurysm clipping (p < 0.01).

Conclusions

From 1993 to 2003, endovascular techniques for aneurysm occlusion have been increasingly used, while the use of surgical clipping procedures has remained stable. Toward the end of the study period, better overall outcomes were observed in the treatment of cerebral aneurysms, both ruptured and unruptured. Large academic centers were associated with better results, particularly for surgical clip placement.

Chlamydia pneumoniae and symptomatic carotid atherosclerotic plaque: a prospective study

OBJECTIVE

To investigate the possible link between symptomatic carotid atherosclerotic plaque and Chlamydia pneumoniae.

BACKGROUND

Recently, several studies have demonstrated that there may be a possible link between Chlamydia pneumonia and carotid atherosclerosis, however the real role of Chlamydia pneumoniae is not completely understood.

METHOD

This is a prospective study with a total of 52 patients analyzed. All patients had been submitted to endarterectomy, and had suffered thrombotic ischemic stroke or transient ischemic attack up to 60 days prior to the surgery. Every patient presented carotid stenosis over 70%. The plaque was removed during the surgery and the laboratory exams were immediately done. Evaluation of Chlamydia pneumoniae DNA was done using polymerase chain reaction (PCR).

RESULTS

The PCR analyses of all 52 patients were negative for Chlamydia pneumoniae.

CONCLUSION

These initial results do not show a relationship between Chlamydia pneumoniae and symptomatic carotid atherosclerotic plaque.

Role of Chlamydia pneumoniae in atherosclerosis

Cardiovascular disease, resulting from atherosclerosis, is a leading cause of global morbidity and mortality. Genetic predisposition and classical environmental risk factors explain much of the attributable risk for cardiovascular events in populations, but other risk factors for the development and progression of atherosclerosis, which can be identified and modified, may be important therapeutic targets. Infectious agents, such as Chlamydia pneumoniae, have been proposed as contributory factors in the pathogenesis of atherosclerosis. In the present review, we consider the experimental evidence that has accumulated over the last 20 years evaluating the role of C. pneumoniae in atherosclerosis and suggest areas for future research in this field.

Use of endovascular coil embolization and surgical clip occlusion for cerebral artery aneurysms

OBJECT

In recent years, endovascular treatment of cerebral artery aneurysms (CAAs) has received greater attention. The authors evaluated patient demographics, endovascular and surgical approaches, and basic outcomes in the treatment of CAAs in a nationally representative administrative database.

METHODS

Using the Nationwide Inpatient Sample from 1998 to 2003, diagnosed CAA coded as either an unruptured or ruptured lesion and treated with surgical clip occlusion, wrapping combined with endovascular repair, or endovascular repair alone was included in the present study.

RESULTS

Treatment of CAAs significantly increased for unruptured (from 4036 to 8334 cases, p = 0.002) but not ruptured (from 9330 to 11,269 cases, p = 0.231) lesions. Endovascular treatment of CAAs in particular also increased in patients with unruptured (from 11 to 43%, p < 0.001) and ruptured (from 5 to 31%, p < 0.001) lesions. In 2003, the mortality rate associated with unruptured CAAs treated using clip occlusion (1.36%) or endovascular repair (1.41%) was similar, whereas rate differences were noted between these treatments for ruptured CAAs (12.7% for clip occlusion compared with 16.6% for endovascular repair; p = 0.05). Endovascular treatment of unruptured CAAs was associated with a shorter length of stay (LOS) and higher rate of discharge to home compared with those for clip occlusion. The LOS was also shorter in patients with endovascularly treated ruptured CAAs. Aneurysm type (odds ratio [OR] 10.1, ruptured lesion), patient age (OR 1.28, each 10 years), comorbid conditions (OR 1.08, each condition), and hospital case volume (OR 0.97, each additional case) were significant predictors of death in the regression model.

CONCLUSIONS

Endovascular techniques for the treatment of CAAs are being used increasingly in the US, although the majority of patients with this pathological entity still undergo surgical clip occlusion. In cases of unruptured CAAs, endovascular treatment is associated with a shorter LOS and higher discharge-to-home rate. Aneurysm status, patient age, comorbid conditions, and hospital case volume are significant predictors of death. Finally, demographic differences exist between the populations presenting with unruptured or ruptured CAAs.

How does the participation of a resident surgeon in procedures for small intracranial aneurysms impact patient outcome?

Object

In this paper the authors' goal was to evaluate whether resident neurosurgeons participating in entry-level aneurysm surgery have a negative impact on patient outcomes.

Methods

The authors searched the database for entry-level aneurysm surgeries (that is, those ≤ 10 mm and located in the internal carotid artery [beyond the paraclinoid segment] and middle cerebral artery) performed in 1991 through 2005. The presence or absence of an advanced resident (in his/her last 3 years of residency) was noted. The analysis was examined in 3-year quintiles.

A total of 355 cases (196 with resident participation and 159 without) were evaluated. Permanent adverse outcomes were seen in 11 patients (3.1% of the total study population), all due to branch artery occlusion. The incidence of permanent adverse outcomes in the first 3 years was 10.7% and 2.4% thereafter. This difference was statistically significant (p = 0.015). There was no difference in the incidence of adverse outcomes when comparing surgery performed with and without participation of an advanced resident.

Conclusions

In this study the authors have demonstrated a learning curve in this series of patients. This study also suggests that involving residents in the repair of small unruptured aneurysms will not compromise patient care. In addition, patients can be informed that the team approach to their surgery is at least as good as having the experienced surgeon performing all aspects of the surgery.

Role of C-reactive protein in coronary risk reduction: focus on primary prevention

Given the limitations of current risk assessment strategies, adjunctive markers are needed to improve the prediction of a first coronary event. Research into the inflammatory nature of atherosclerosis suggests that inflammatory-response proteins may serve as potential predictors of clinical events. One in particular, C-reactive protein, has been the focus of much attention. Epidemiologic studies have shown a fairly consistent independent association between high-sensitivity C-reactive protein (hs-CRP) elevations and coronary risk, although a causal relation has not yet been established. Given this association, current guidelines recommend the optional use of hs-CRP to predict enhanced absolute risk in selected patients. The use of a marker in general clinical practice should be based on statistical measures that show incremental benefit over established risk factors and on randomized clinical trials in which therapy initiated as a result of marker screening improves patient outcomes. Thus far, statistical evidence concerning the incremental benefit of hs-CRP is not conclusive. Justification for the Use of Statins in Primary Prevention: An Intervention Trial Evaluating Rosuvastatin (JUPITER) is now being conducted to compare the efficacy of statin therapy versus placebo in subjects considered to be at increased risk on the basis of hs-CRP elevations, despite low to normal levels of low-density lipoprotein cholesterol. In conclusion, although epidemiologic studies suggest that low-grade C-reactive protein elevations are independently associated with coronary risk, more complete evidence is needed to validate the use of hs-CRP as a risk assessment tool in general practice and as a target for therapy in individual patients.

Distinct NKT cell subsets are induced by different Chlamydia species leading to differential adaptive immunity and host resistance to the infections

We investigated the role of NKT cells in immunity to Chlamydia pneumoniae and Chlamydia muridarum infections using a combination of knockout mice and specific cellular activation approaches. The NKT-deficient mice showed exacerbated susceptibility to C. pneumoniae infection, but more resistance to C. muridarum infection. Activation of NKT reduced C. pneumoniae in vivo growth, but enhanced C. muridarum infection. Cellular analysis of invariant NKT cells revealed distinct cytokine patterns following C. pneumoniae and C. muridarum infections, i.e., predominant IFN-gamma in the former, while predominant IL-4 in the latter. The cytokine patterns of CD4(+) and CD8(+) T cells matched those of NKT cells. Our data provide in vivo evidence for a functionally diverse role of NKT cells in immune response to two intracellular bacterial pathogens. These results suggest that distinct NKT subsets are induced by even biologically closely related pathogens, thus leading to differential adaptive immune response and infection outcomes.

Local Markers for Prediction of Women at Higher Risk of Developing Sequelae to Chlamydia trachomatis Infection

PROBLEM

Chlamydial infections are often associated with various fertility-related disorders. Serological prediction of these has limitations, as they do not differentiate between past and current infections. Thus, we looked for local markers that could predict more precisely women at higher risk of developing severe complications.

METHOD OF STUDY

A total of 320 Chlamydia trachomatis positive women with or without fertility disorders were tested for the prevalence of immunoglobulin A antibodies to synthetic peptides of chlamydial heat-shock protein 60 (cHSP60) and cHSP10 along with cervical interferon-gamma (IFN-gamma) and serum C-reactive protein (CRP) levels.

RESULTS

Positive IFN-gamma level was the single best predictor for fertility disorder [odds ratio (OR) 15.4]. The predictive value of IFN-gamma could be significantly improved only by the addition of CRP test (OR 37.9).

CONCLUSION

Positive IFN-gamma levels in cervical washes along with elevated CRP levels could be used to predict women who are at higher risk of developing fertility disorders.

Association of Chlamydia pneumoniae infection and carotid intima-media wall thickness in Japanese Americans

BACKGROUND

Chlamydia pneumoniae (Cp) infection has been proposed as a risk factor for coronary artery disease (CAD), but it remains unclear whether Cp plays a role in the progression of early stage carotid atherosclerosis.

METHODS AND RESULTS

The associations among Cp IgG/IgA antibodies, inflammation markers such as C-reactive protein (CRP) and interleukin (IL)-6, and the maximal progression of carotid intima-media wall thickness (max IMT) were evaluated using ultrasonography in 259 Japanese Americans. The presence of Cp IgG or IgA antibodies itself did not show significant correlation with max IMT after adjustment for age and sex. However, in the Cp IgG seropositive group, the subjects with high IL-6 levels showed more pronounced max IMT progression than those with low IL-6 levels after adjustment of the other CAD risk factors. Moreover, in the Cp IgA seropositive group, the subjects with high CRP or IL-6 levels had significantly higher levels of max IMT compared with those with low CRP or IL-6.

CONCLUSIONS

The results support the hypothesis that a chronic latent Cp infection with inflammation might accelerate the development of early stage atherosclerotic lesions.

Chlamydia pneumoniae and vascular disease: an update

Exposure to Chlamydia pneumoniae is extremely common, and its incidence increases with age. C pneumoniae infection is strongly associated with coronary artery disease, as well as with atherosclerosis of the carotid artery, aorta, and peripheral arteries. This association has been shown in seroepidemiologic studies and by direct detection of the organism in atherosclerotic lesions by immunohistochemistry, polymerase chain reaction, electron microscopy, and tissue culture. Animal models of atherosclerosis have been used to study the role of C pneumoniae in the initiation and progression of atherosclerotic disease. The association of this organism with cardiovascular complications has inspired many human trials of antibiotics for the secondary prevention of atherosclerosis. C pneumoniae can infect several types of cells, including circulating macrophages, arterial smooth muscle cells, and vascular endothelial cells, causing the secretion of proinflammatory cytokines and procoagulants by endothelial cells and foam cell formation by infected macrophages. This report reviews the role of C pneumoniae in atherogenesis in light of recent, large antibiotic treatment trials, animal studies, and in vitro studies. The role of Chlamydia heat shock protein as a potential mediator of this harmful effect is also reviewed.

Chlamydia trachomatis-associated tubal factor subfertility: Immunogenetic aspects and serological screening

Chlamydia (C.) trachomatis female genital tract infections usually remain asymptomatic and untreated. Therefore, an adequate immune response, rather than antibiotic treatment, is essential to clear the pathogen. Most women will effectively clear C. trachomatis infections, but some will have persistent C. trachomatis infections, which may ascend to the upper genital tract and increase the risk of tubal factor subfertility. Pattern recognition receptors (PRRs) of the toll-like receptor (TLR) and nucleotide-binding oligomerization domain (NOD) families recognize C. trachomatis and initiate the immune response. Host immune factors are determinants of the course of C. trachomatis infections. Genetic variations in TLR and NOD genes may affect receptor function, leading to inadequate recognition of C. trachomatis, an inadequate immune response, and consequently an increased risk of persistence and late sequelae. For the risk assessment of tubal pathology in subfertile women, C. trachomatis immunoglobulin (Ig) G antibody testing (CAT) in serum is widely used. A positive CAT is indicative of a previous infection but not of a persistent infection. Measuring serological markers of persistence, of which C-reactive protein (CRP) seems promising, in CAT-positive women may identify a subgroup of subfertile women with persistent C. trachomatis infections and the highest risk of tubal pathology.

No evidence for a direct role of Helicobacter pylori and Mycoplasma pneumoniae in carotid artery atherosclerosis

BACKGROUND

That infections with certain pathogens, by initiating an inflammatory response, may contribute to the development of atherosclerosis is suggested by clinical and experimental evidence.

AIM

To analyse atherosclerotic plaques of the carotid artery, samples of apparently healthy greater saphenous veins and circulating leucocytes from the same individual patients for the presence of Helicobacter pylori and Mycoplasma pneumoniae.

METHODS

Samples from 36 patients undergoing carotid endarterectomy for symptomatic carotid artery stenosis were analysed by polymerase chain reaction for the presence of DNA specific for H. pylori and M. pneumoniae. IgG antibody titres against H. pylori and M pneumoniae and plasma levels of soluble E-selectin, soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 were determined.

RESULTS

M. pneumoniae-specific DNA was detected in the atherosclerotic plaques of 13 of 36 (36.1%) patients, in the saphenous veins of 9 of 36 (25%) patients and in the leucocytes of 27 of 36 (75%) patients. No salient association was observed between the presence of M. pneumoniae-specific DNA in leucocytes and atherosclerotic plaques or veins. A marked correlation between the presence of M. pneumoniae in the respective specimens and the studied inflammatory markers or the presence of anti-M. pneumoniae antibodies was not observed. H. pylori-specific DNA could not be detected in the specimens tested.

CONCLUSIONS

The absence of H. pylori and the random distribution of M. pneumoniae in tissue samples obtained from patients with symptomatic carotid artery stenosis do not support a role for these pathogens in the development of atherosclerosis due to a direct interaction of the bacteria with the vasculature.

The effect of infections and vaccinations on stroke risk

There is increasing evidence that, in addition to conventional risk factors, acute and chronic infectious diseases increase the risk of stroke. Acute infection, mainly respiratory, and both bacterial and viral infection, represent temporarily active trigger factors for cerebral ischemia. Chronic infectious diseases that may increase the risk of stroke include periodontitis, chronic bronchitis and infections with microbial antigens, such as Helicobacter pylori and Chlamydia pneumoniae. From observational studies, there is evidence that vaccination against influenza is associated with a reduced risk of stroke, myocardial infarction and all-cause mortality. This report provides an overview on the influence of infection on stroke risk and potential anti-infective strategies that may play a future role in stroke prevention.

Future directions for recanalization therapy in acute ischemic stroke

Currently, the only treatment approved by the US Food and Drug Administration for the treatment of acute stroke is the intravenous recombinant tissue plasminogen activator, which must be administered within a 3 h window. The majority of ischemic stroke patients do not receive intravenous thrombolysis, primarily because they enter the healthcare system too late. Alternative treatment strategies being used or investigated include intra-arterial thrombolysis, endovascular clot disruption, and manipulation and angioplasty with or without stenting. The most promising new revascularization technologies beyond conventional thrombolysis for acute ischemic stroke are ultrasound-enhanced thrombolysis, mechanical clot extraction devices and stent angioplasty. Advances in neuroimaging may allow physicians to determine the etiology of a stroke and tailor treatment accordingly for the maximal clinical benefit for affected patients.

Extracranial—intracranial bypass in the treatment of occlusive cerebrovascular disease and intracranial aneurysms in the United States between 1992 and 2001: a population-based study

Object. The authors assessed the results of extracranial—intracranial (EC—IC) bypass surgery in the treatment of occlusive cerebrovascular disease and intracranial aneurysms in the US between 1992 and 2001 by using population-based methods.

Methods. This is a retrospective cohort study based on data from the Nationwide Inpatient Sample (Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality, Rockville, MD). Five hundred fifty-eight operations were performed at 158 hospitals by 115 identified surgeons. The indications for surgery were cerebral ischemia in 74% of the operations (2.4% mortality rate), unruptured aneurysms in 19% of the operations (7.7% mortality rate), and ruptured aneurysms in 7% of the operations (21% mortality rate). Overall, 4.6% of the patients died and 4.7% of the patients were discharged to long-term facilities, 16.4% to short-term facilities, and 74.2% to their homes. The annual number of admissions in the US increased from 190 per year (1992–1996) to 360 per year (1997–2001), whereas the mortality rates increased from 2.8% (1992–1996) to 5.7% (1997–2001).

The median annual number of procedures was three per hospital (range one–27 operations) or two per surgeon (range one–21 operations). For 29% of patients, their bypass procedure was the only one recorded at their particular hospital during that year; for these institutions the mean annual caseload was 0.4 admissions per year. For 42% of patients, their particular surgeon performed no other bypass procedure during that year. Older patient age (p < 0.001) and African-American race (p = 0.005) were risk factors for adverse outcome. In a multivariate analysis in which adjustments were made for age, sex, race, diagnosis, admission type, geographic region, medical comorbidity, and year of surgery, high-volume hospitals less frequently had an adverse discharge disposition (odds ratio 0.54, p = 0.03).

Conclusions. Most EC—IC bypasses performed in the US during the last decade were performed for occlusive cerebrovascular disease. Community mortality rates for aneurysm treatment including bypass procedures currently exceed published values from specialized centers and, during the period under study, the mortality rates increased with time for all diagnostic subgroups. This technically demanding procedure has become a very low-volume operation at most US centers.

A randomized trial in patients undergoing percutaneous coronary angioplasty: roxithromycin does not reduce clinical restenosis but angioplasty increases antibody concentrations against Chlamydia pneumoniae

BACKGROUND

Elevated antibodies against Chlamydia pneumoniae have been associated with coronary artery disease. In patients undergoing percutaneous coronary angioplasty, we therefore investigated the effect of roxithromycin on symptomatic restenosis and determined antichlamydial antibodies as well as inflammatory and immunological parameters.

METHODS

A total of 327 patients undergoing coronary angioplasty were randomized to roxithromycin or placebo and followed-up for 1 year. Antibodies were determined by microimmunofluorescence and enzyme-linked immunosorbent assay; C-reactive protein, interleukin-10, tumor necrosis factor-alpha (TNF-alpha), and eotaxin were determined by enzyme-linked immunosorbent assay.

RESULTS

Although the frequency of restenosis was not affected by roxithromycin (25 restenoses vs 32 in the control group), antichlamydial antibodies increased during follow-up (anti-CP IgG +12 +/- 2%, P < .001). Concentrations of TNF-alpha and eotaxin increased as well (TNF-alpha +9 +/- 1% and eotaxin +10 +/- 2%) and correlated with antichlamydial antibody concentrations (TNF-alpha, r = 0.23, P = .02; eotaxin, r = 0.32, P = .002).

CONCLUSIONS

Treatment with roxithromycin was not associated with a reduction of symptomatic restenoses. During follow-up, a marked increase in antichlamydial antibodies, TNF-alpha, and eotaxin was observed, suggesting that angioplasty-induced plaque rupture induces a specific immunological response without activation of inflammatory mechanisms as represented by C-reactive protein. Whether this mechanism occurs in all plaque ruptures remains to be determined.

Role of anti-infective strategies in the prevention of stroke

Case-control studies and a few prospective studies have indicated that chronic infections may add to the risk of stroke and that acute infections may act as trigger factors for stroke. Such chronic infections include periodontal disease, infection with Chlamydia pneumoniae or Helicobacter pylori, and chronic bronchitis. A causal role of these infectious diseases has not been proved, given conflicting study results, possible residual confounding in observational studies, and the lack of evidence from interventional trials. Therefore, special treatment regimens for stroke prevention based on serologic or genomic evidence of infection are not indicated outside of randomized studies at present. However, the preliminary available evidence suggests that in patients with previous cerebral ischemia, clinically diagnosed chronic infections should be taken seriously and should receive the treatment that is indicated according to current guidelines. This may include appropriate treatment of moderate or severe periodontitis and of chronic bronchitis. Inflammatory parameters (eg, C-reactive protein, leukocyte count, fibrinogen) are independently associated with the risk of first or recurrent stroke. The question of whether these indexes are causally related to stroke or merely represent risk markers is not sufficiently clarified. Their use in monitoring individual risk in daily clinical practice is limited at present by the lack of clearly defined therapeutic strategies to modify these parameters, although statins and other drugs can influence inflammatory markers. Observational studies have shown that influenza vaccination is significantly and independently associated with a reduced risk of stroke and myocardial infarction. Although interventional studies in stroke are lacking, it is recommendable that in accordance with current guidelines patients with previous vascular disease, including stroke, patients with high risk of stroke, and all subjects above age 60, receive an influenza vaccination annually.

Craniotomy for meningioma in the United States between 1988 and 2000: decreasing rate of mortality and the effect of provider caseload

Object. The goal of this study was to determine the risk of adverse outcomes after contemporary surgical treatment of meningiomas in the US and trends in patient outcomes and patterns of care.

Methods. The authors performed a retrospective cohort study by using the Nationwide Inpatient Sample covering the period of 1988 to 2000. Multivariate regression models with disposition end points of death and hospital discharge were used to test patient, surgeon, and hospital characteristics, including volume of care, as outcome predictors.

Multivariate analyses revealed that larger-volume centers had lower mortality rates for patients who underwent craniotomy for meningioma (odds ratio [OR] 0.74, 95% confidence interval [CI] 0.59–0.93, p = 0.01). Adverse discharge disposition was also less likely at high-volume hospitals (OR 0.71, 95% CI 0.62–0.80, p < 0.001). With respect to the surgeon caseload, there was a trend toward a lower rate of mortality after surgery when higher-caseload providers were involved, and a significantly less frequent adverse discharge disposition (OR 0.71, 95% CI 0.62–0.80, p <, 0.001).

The annual meningioma caseload in the US increased 83% between 1988 and 2000, from 3900 patients/year to 7200 patients/year. In-hospital mortality rates decreased 61%, from 4.5% in 1988 to 1.8% in 2000. Reductions in the mortality rates were largest at high-volume centers (a 72% reduction in the relative mortality rate at largest-volume-quintile centers, compared with a 6% increase in the relative mortality rate at lowest-volume-quintile centers). The number of US hospitals where craniotomies were performed for meningiomas increased slightly. Fewer centers hosted one meningioma resection annually, whereas the largest centers had disproportionate increases in their caseloads, indicating a modest centralization of meningioma surgery in the US during this interval.

Conclusions. The mortality and adverse hospital discharge disposition rates were lower when meningioma surgery was performed by high-volume providers. The annual US caseload increased, whereas the mortality rates decreased, especially at high-volume centers.

High prevalence of Chlamydia pneumoniae antibodies and increased high-sensitive C-reactive protein in patients with vascular dementia

OBJECTIVES

To determine the relationships between Chlamydia pneumoniae infection, carotid atherosclerosis, and dyslipidemia in patients with vascular dementia (VaD) and Alzheimer's disease (AD).

DESIGN

Case control study.

SETTING

Showa University Karasuyama Hospital, Tokyo, Japan.

PARTICIPANTS

One hundred twenty-four elderly subjects: 31 with VaD, 61 with AD, and 32 age-matched controls without dementia.

MEASUREMENTS

Presence of antibodies to C. pneumoniae (immunoglobulin G (IgG) and IgA), the serum concentrations of high-sensitive C-reactive protein (hs-CRP) and atherogenic lipoproteins, and the carotid artery intima-media thickness (IMT) and plaques were determined.

RESULTS

Age; body mass index; systolic and diastolic blood pressures; and fasting plasma glucose, hemoglobin A(1c), high-density lipoprotein cholesterol, and apolipoprotein A-I, B, and E concentrations did not differ significantly between the three groups, but the mean IMT and frequency of atherosclerotic plaques in the carotid arteries, as well as the serum concentrations of low-density lipoprotein cholesterol (LDL-C), lipoprotein(a), and lipid peroxides were significantly greater in VaD patients than in AD patients or nondemented controls. Hs-CRP concentrations and prevalence of C. pneumoniae IgG and IgA antibodies also were significantly higher in VaD patients than in AD patients and nondemented controls. Multiple logistic regression analysis revealed that carotid IMT and plaques, LDL-C, lipid peroxides, hs-CRP, and IgG and IgA C. pneumoniae seropositivity were independent risk factors for VaD.

CONCLUSION

These results suggest that carotid atherosclerosis, atherogenic lipoproteins, and C. pneumoniae infection (as documented by the IgG and IgA seropositivity together with increased hs-CRP) may be VaD risk factors.

Serological markers of persistent C. trachomatis infections in women with tubal factor subfertility

BACKGROUND

Persistent C. trachomatis infections are assumed to increase the risk of tubal pathology. We studied whether serological markers, assumed to be associated with persistent C. trachomatis infections, could identify subfertile women at risk of tubal pathology.

METHODS

Sera of 313 subfertile women, who all underwent a laparoscopy with tubal testing to assess the grade of tubal pathology, were tested for the presence of immunoglobulin (Ig) G and IgA antibodies to C. trachomatis, IgG antibodies to chlamydia heat shock protein 60 (cHSP60) and C-reactive protein (CRP).

RESULTS

C. trachomatis IgA, cHSP60 IgG and CRP, all serological markers of persistent infections, were significantly more prevalent in women with tubal pathology as compared to those without tubal pathology. The predictive value of the currently used screening test for tubal pathology (IgG to C. trachomatis) could be significantly improved by adding the CRP test.

CONCLUSIONS

In subfertile women with tubal pathology, serological markers of persistent C. trachomatis infections are significantly more common as compared to women without tubal pathology. C. trachomatis IgG-positive subfertile women with slightly elevated (< 10 mg/l) CRP levels are at highest risk of persistent C. trachomatis infections and tubal pathology.