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Community-acquired pneumonia (CAP) is complicated by cardiovascular events as myocardial infarction and stroke but the underlying mechanism is still unclear. We hypothesized that endothelial dysfunction may be implicated and that endotoxemia may have a role.Fifty patients with CAP and 50 controls were enrolled. At admission and at discharge, flow-mediated dilation (FMD), serum levels of endotoxins and oxidative stress, as assessed by serum levels of nitrite/nitrate (NOx) and isoprostanes, were studied.At admission, a significant difference between patients with CAP and controls was observed for FMD (2.1±0.3 vs 4.0±0.3%, p0.001), serum endotoxins (157.8±7.6 vs 33.1±4.8pg/ml), serum isoprostanes (341±14 vs 286±10 pM, p=0.009) and NOx (24.3±1.1 vs 29.7±2.2μM). Simple linear correlation analysis showed that serum endotoxins significantly correlated with Pneumonia Severity Index score (Rs=0.386, p=0.006). Compared to baseline, at discharge CAP patients showed a significant increase of FMD and NOx (from 2.1±0.3 to 4.6±0.4%, p0.001 and from 24.3±1.1 to 31.1±1.5μM, p0.001, respectively) and a significant decrease of serum endotoxins and isoprostanes (from 157.8±7.6 to 55.5±2.3pg/ml, p0.001, and from 341±14 to 312±14 pM, p0.001, respectively). Conversely, no changes for FMD, NOx, serum endotoxins and isoprostanes were observed in controls between baseline and discharge. Changes of FMD significantly correlated with changes of serum endotoxins (Rs=-0.315; p=0.001).The study provides the first evidence that CAP is characterized by impaired FMD with a mechanism potentially involving endotoxin production and oxidative stress.

Adults hospitalized for community-acquired pneumonia (CAP) have an increased risk of myocardial infarction. Corticosteroid treatment lowers CAP morbidity and mortality, but it is not known whether it influences in-hospital myocardial infarction.The aim of the present study was to investigate the potential interplay between corticosteroid treatment and in-hospital myocardial infarction in adults with CAP.We retrospectively analyzed adults with CAP referred to the University Hospital Policlinico Umberto I (Rome, Italy), consecutively recruited, and prospectively followed until discharge. The primary outcome was the occurrence of myocardial infarction during hospitalization. We used propensity score-adjusted Cox models to examine the association between corticosteroid use and myocardial infarction.Seven hundred fifty-eight patients (493 males, 265 females; mean ± standard deviation age, 71.7 ± 14.4 yr) were included in the study. Of these, 241 (32%) were treated with systemic corticosteroids (methylprednisolone, betamethasone, or prednisone). During follow-up, 62 (8.2%) had a myocardial infarction during their hospitalization (incidence, 0.72 per 100 person-days; 95% confidence interval [CI], 0.55 to 0.92). Those treated with corticosteroids had a lower incidence of myocardial infarction (0.42 per 100 person-days) than those not treated with corticosteroids (0.89 per 100 person-days; absolute rate difference, -0.48 per 100 person-days; 95% CI, -0.85 to -0.10). In a propensity score-adjusted Cox model, corticosteroid use was associated with a lower incidence of myocardial infarction (hazard ratio, 0.46; 95% CI, 0.24 to 0.88; P = 0.02).We found that in-hospital corticosteroid treatment was associated with a lower incidence of myocardial infarction in adults hospitalized with CAP.

Platelet activation seems to be implicated in the cardiovascular events occurring in patients with community-acquired pneumonia (CAP) but the underlying mechanism is still unclear. Aim of the study was to assess the mechanism involved in platelet activation in CAP patients.Two-hundred-seventy-eight consecutive patients hospitalized for CAP were recruited and followed-up until discharge. Hospitalized patients matched for sex, age and comorbidities but without acute infectious diseases were used as controls.At hospital admission patients disclosed enhanced plasma levels of sP-selectin, a maker of in-vivo platelet activation, serum sNOX2-dp, a marker of NADPH-oxidase activation, serum Lipopolysaccharide (LPS) and serum zonulin, a marker of gut permeability, compared to controls (p 0.001). Baseline sP-selectin was independently associated to serum LPS, sNOX2-sp and Pneumonia Severity Index score (p 0.001). Plasma sP-selectin, serum sNOX2-dp, LPS and zonulin coincidentally decreased at hospital discharge (p 0.001). An in vitro study showed that LPS, at concentration similar to that found in CAP patients, induced sP-selectin release by agonist-activated platelets, a phenomenon that was counteract by treating cells with gp91ds-tat, a specific inhibitor of NOX2.CAP patients display enhanced platelet activation, which is related to LPS-mediated NOX2 activation. Enhanced gut permeability seems be implicated in enhancing circulating levels of LPS.

Community-acquired pneumonia (CAP) is complicated by cardiac events in the early phase of the disease. Aim of this study was to assess if these intrahospital cardiac complications may account for overall mortality and cardiovascular events occurring during a long-term follow-up. Three hundred one consecutive patients admitted to the University-Hospital, Policlinico Umberto I, with community-acquired pneumonia were prospectively recruited and followed up for a median of 17.4 months. Primary end point was the occurrence of death for any cause, and secondary end point was the occurrence of cardiovascular events (cardiovascular death, nonfatal myocardial infarction [MI], and stroke). During the intrahospital stay, 55 patients (18%) experienced a cardiac complication. Of these, 32 had an MI (29 non-ST-elevation MI and 3 ST-elevation MI) and 30 had a new episode of atrial fibrillation (7 nonmutually exclusive events). During the follow-up, 89 patients died (51% of patients with an intrahospital cardiac complication and 26% of patients without, p0.001) and 73 experienced a cardiovascular event (47% of patients with and 19% of patients without an intrahospital cardiac complication, p0.001). A Cox regression analysis showed that intrahospital cardiac complications, age, and Pneumonia Severity Index were significantly associated with overall mortality, whereas intrahospital cardiac complications, age, hypertension, and diabetes were significantly associated with cardiovascular events during the follow-up. In conclusion, this prospective study shows that intrahospital cardiac complications in the early phase of pneumonia are associated with an enhanced risk of death and cardiovascular events during long-term follow-up.

Background Urinary 8‐iso‐ PGF 2α, a marker of oxidative stress, is influenced by the activation of NOX 2. It is unclear if platelets 8‐iso‐ PGF 2α contribute to urinary 8‐iso‐ PGF 2α. Methods and Results In a cross‐sectional study, platelet, urinary, and serum 8‐iso‐ PGF 2α were determined in subjects with downregulation (X‐linked chronic granulomatous disease [ X‐CGD ], n=25) and upregulation (type II diabetic patients [T2D], n=121) of NOX 2 and 153 controls matched for sex and age. In diabetic patients (n=18), the above variables were repeated before and after 7 days treatment with 100 mg/day aspirin or 100 mg/day aspirin plus 40 mg/day atorvastatin. In vitro study was performed to see the contribution of blood cells to serum 8‐iso‐ PGF 2α. Compared with controls, X‐CGD patients had lower platelet, serum, and urinary 8‐iso‐ PGF 2α values; conversely, diabetic patients had higher values of 8‐iso‐ PGF 2α compared with controls. Urinary 8‐iso‐ PGF 2α significantly correlated with both platelet and serum 8‐iso‐ PGF 2α in the 2 cohorts. A parallel increase of platelet, serum, and urinary 8‐iso‐ PGF 2α by aspirin and a parallel decrease by aspirin plus atorvastatin were detected in the interventional study. In vitro study demonstrated that platelets contribute to 37% of serum 8‐iso‐ PGF 2α and that only 13% of it is of extravascular origin. Conclusions The study suggests that NOX 2 contributes to the formation of 8‐iso‐ PGF 2α in both platelets and urine. The direct correlation between platelet and urinary 8‐iso‐ PGF 2α suggests that, at least partly, urinary 8‐iso‐ PGF 2α reflects platelet 8‐iso‐ PGF 2α production. Analysis of serum 8‐iso‐ PGF 2α may represent a novel tool to investigate the production of 8‐iso‐ PGF 2α by blood cells including platelets. Clinical Trial Registration URL: ClinicalTrials.gov. Unique Identifier: NCT01250340 .