NFκB and NLRP3/NLRC4 inflammasomes regulate differentiation, activation and functional properties of monocytes in response to distinct SARS-CoV-2 proteins.

Increased recruitment of transitional and non-classical monocytes in the lung during SARS-CoV-2 infection is associated with COVID-19 severity. However, whether specific innate sensors mediate the activation or differentiation of monocytes in response to different SARS-CoV-2 proteins remain poorly characterized. Here, we show that SARS-CoV-2 Spike 1 but not nucleoprotein induce differentiation of monocytes into transitional or non-classical subsets from both peripheral blood and COVID-19 bronchoalveolar lavage samples in a NFκB-dependent manner, but this process does not require inflammasome activation. However, NLRP3 and NLRC4 differentially regulated CD86 expression in monocytes in response to Spike 1 and Nucleoprotein, respectively. Moreover, monocytes exposed to Spike 1 induce significantly higher proportions of Th1 and Th17 CD4 + T cells. In contrast, monocytes exposed to Nucleoprotein reduce the degranulation of CD8 + T cells from severe COVID-19 patients. Our study provides insights in the differential impact of innate sensors in regulating monocytes in response to different SARS-CoV-2 proteins, which might be useful to better understand COVID-19 immunopathology and identify therapeutic targets.

Is the long-term mortality similar in COVID-19 and community-acquired pneumonia?

Introduction: There are no data on the association of type of pneumonia and long-term mortality by the type of pneumonia (COVID-19 or community-acquired pneumonia [CAP]) on long-term mortality after an adjustment for potential confounding variables. We aimed to assess the type of pneumonia and risk factors for long-term mortality in patients who were hospitalized in conventional ward and later discharged. Methods: Retrospective analysis of two prospective and multicentre cohorts of hospitalized patients with COVID-19 and CAP. The main outcome under study was 1-year mortality in hospitalized patients in conventional ward and later discharged. We adjusted a Bayesian logistic regression model to assess associations between the type of pneumonia and 1-year mortality controlling for confounders. Results: The study included a total of 1,693 and 2,374 discharged patients in the COVID-19 and CAP cohorts, respectively. Of these, 1,525 (90.1%) and 2,249 (95%) patients underwent analysis. Until 1-year follow-up, 69 (4.5%) and 148 (6.6%) patients from the COVID-19 and CAP cohorts, respectively, died (p = 0.008). However, the Bayesian model showed a low probability of effect (PE) of finding relevant differences in long-term mortality between CAP and COVID-19 (odds ratio 1.127, 95% credibility interval 0.862-1.591; PE = 0.774). Conclusion: COVID-19 and CAP have similar long-term mortality after adjusting for potential confounders.

Tumor-Associated Granulomas Preceding a Diagnosis of Thoracic Sarcoidosis: A Retrospective, Single-Center Cohort Study.

There is a relationship between systemic sarcoidosis (SS) and malignancy. Sarcoidosis results from an exaggerated immune response in genetically susceptible individuals. In oncologic patients with sarcoidosis, tumoral antigens and antineoplastic treatment are considered potential triggering factors. The observation of a patient with granulomas in a parotid carcinoma who later developed SS led us to review the previous tumors of patients with SS. The aim of the study is to see whether granulomas were already present in the tumors that preceded sarcoidosis. We identified 196 sarcoidosis patients, 47 of whom had previously had a tumor. We were able to review 29 cases, 12 of which showed tumor-associated granulomas (TAGs) (41.4%). This ratio is much higher than that of the normal population (4.4-13.8). We analyzed five control patients without sarcoidosis for each tumor. In conclusion, we observed an increased number of TAGs in patients who later developed SS. This finding reinforces a pathogenic relationship between SS and neoplasia. The histology of tumors in patients with SS should be reviewed in an attempt to identify granulomas.

The role of bronchoscopy in patients with SARS-CoV-2 pneumonia.

BACKGROUND: The role of bronchoscopy in coronavirus disease 2019 (COVID-19) is a matter of debate. PATIENTS AND METHODS: This observational multicentre study aimed to analyse the prognostic impact of bronchoscopic findings in a consecutive cohort of patients with suspected or confirmed COVID-19. Patients were enrolled at 17 hospitals from February to June 2020. Predictors of in-hospital mortality were assessed by multivariate logistic regression. RESULTS: A total of 1027 bronchoscopies were performed in 515 patients (age 61.5±11.2 years; 73% men), stratified into a clinical suspicion cohort (n=30) and a COVID-19 confirmed cohort (n=485). In the clinical suspicion cohort, the diagnostic yield was 36.7%. In the COVID-19 confirmed cohort, bronchoscopies were predominantly performed in the intensive care unit (n=961; 96.4%) and major indications were: difficult mechanical ventilation (43.7%), mucus plugs (39%) and persistence of radiological infiltrates (23.4%). 147 bronchoscopies were performed to rule out superinfection, and diagnostic yield was 42.9%. There were abnormalities in 91.6% of bronchoscopies, the most frequent being mucus secretions (82.4%), haematic secretions (17.7%), mucus plugs (17.6%), and diffuse mucosal hyperaemia (11.4%). The independent predictors of in-hospital mortality were: older age (OR 1.06; p<0.001), mucus plugs as indication for bronchoscopy (OR 1.60; p=0.041), absence of mucosal hyperaemia (OR 0.49; p=0.041) and the presence of haematic secretions (OR 1.79; p=0.032). CONCLUSION: Bronchoscopy may be indicated in carefully selected patients with COVID-19 to rule out superinfection and solve complications related to mechanical ventilation. The presence of haematic secretions in the distal bronchial tract may be considered a poor prognostic feature in COVID-19.

Challenges in understanding host genetics and severity of community-acquired pneumonia.

This study found no association of the top two associated FER variants with severity of community-acquired pneumonia. Precise characterisation of phenotypes may be required in order to unravel the genetic mechanisms predisposing to poor outcome in sepsis. https://bit.ly/3jc9SmR.

Should MASP-2 Deficiency Be Considered a Primary Immunodeficiency? Relevance of the Lectin Pathway.

Mannose-binding lectin (MBL)-associated serine protease-2 (MASP-2) is an indispensable enzyme for the activation of the lectin pathway of complement. Its deficiency is classified as a primary immunodeficiency associated to pyogenic bacterial infections, inflammatory lung disease, and autoimmunity. In Europeans, MASP-2 deficiency, due to homozygosity for c.359A > G (p.D120G), occurs in 7 to 14/10,000 individuals. We analyzed the presence of the p.D120G mutation in adults (increasing the sample size of our previous studies) and children. Different groups of patients (1495 adults hospitalized with community-acquired pneumonia, 186 adults with systemic lupus erythematosus, 103 pediatric patients with invasive pneumococcal disease) and control individuals (1119 healthy adult volunteers, 520 adult patients without history of relevant infectious diseases, and a pediatric control group of 311 individuals) were studied. Besides our previously reported MASP-2-deficient healthy adults, we found a new p.D120G homozygous individual from the pediatric control group. We also reviewed p.D120G homozygous individuals reported so far: a total of eleven patients with a highly heterogeneous range of disorders and nine healthy controls (including our four MASP-2-deficient individuals) have been identified by chance in association studies. Individuals with complete deficiencies of several pattern recognition molecules of the lectin pathway (MBL, collectin-10 and collectin-11, and ficolin-3) as well as of MASP-1 and MASP-3 have also been reviewed. Cumulative evidence suggests that MASP-2, and even other components of the LP, are largely redundant in human defenses and that individuals with MASP-2 deficiency do not seem to be particularly prone to infectious or autoimmune diseases.

Early and Late Cardiovascular Events in Patients Hospitalized for Community-Acquired Pneumonia. / Eventos cardiovasculares tempranos y tardíos en pacientes ingresados por neumonía adquirida en la comunidad.

INTRODUCTION: Community-acquired pneumonia increases the risk of cardiovascular events (CVE). The objective of this study was to analyze host, severity, and etiology factors associated with the appearance of early and late events and their impact on mortality. METHOD: Prospective multicenter cohort study in patients hospitalized for pneumonia. CVE and mortality rates were collected at admission, 30-day follow-up (early events), and one-year follow-up (late events). RESULTS: In total, 202 of 1,967 (10.42%) patients presented early CVE and 122 (6.64%) late events; 16% of 1-year mortality was attributed to cardiovascular disease. The host risk factors related to cardiovascular complications were: age ≥65 years, smoking, and chronic heart disease. Alcohol abuse was a risk factor for early events, whereas obesity, hypertension, and chronic renal failure were related to late events. Severe sepsis and Pneumonia Severity Index (PSI) ≥3 were independent risk factors for early events, and only PSI ≥3 for late events. Streptococcus pneumoniae was the microorganism associated with most cardiovascular complications. Developing CVE was an independent factor related to early (OR 2.37) and late mortality (OR 4.05). CONCLUSIONS: Age, smoking, chronic heart disease, initial severity, and S. pneumoniae infection are risk factors for early and late events, complications that have been related with an increase of the mortality risk during and after the pneumonia episode. Awareness of these factors can help us make active and early diagnoses of CVE in hospitalized CAP patients and design future interventional studies to reduce cardiovascular risk.

Neutrophil Count Percentage and Neutrophil-Lymphocyte Ratio as Prognostic Markers in Patients Hospitalized for Community-Acquired Pneumonia. / Estudio del porcentaje de neutrófilos y el cociente de neutrófilos-linfocitos como marcadores pronósticos en pacientes hospitalizados por neumonía adquirida en la comunidad.

INTRODUCTION: Community-acquired pneumonia (CAP) is a common serious infection. This study aimed to evaluate the prognostic utility of neutrophil count percentage (NCP) and neutrophil-lymphocyte ratio (NLR) in patients with CAP. METHODS: Retrospective study of hospitalized patients with CAP. Patients had a blood test at admission and 3-5 days after hospitalization (early-stage test). The main outcome variables were 30-day and 90-day mortality. RESULTS: Two hundred and 9patients were included. Patients who survived had significant reductions in both NCP and NLR between admission and the day 3-5 blood tests (from 85.8% to 65.4% for NCP and from 10.1 to 3.2 for NLR). Twenty-five patients died in the first 90 days. Patients who died had lower, non-significant reductions in NCP (from 84.8% to 74%) and NLR (from 9.9 to 6.9) and significantly higher early-stage NCP and NLR than those who survived. NCP values higher than 85% and NLR values higher than 10 in the early-stage blood test were associated with a higher risk of mortality, even after multivariate adjustment (HR for NCP: 12; HR for NLR: 6.5). CONCLUSION: NCP and NLR are simple, low-cost parameters with prognostic utility, especially when measured 3-5 days after CAP diagnosis. High NLR and/or NCP levels are associated with a greater risk of mortality at 90 days.

Correction: Inflammation biomarkers in blood as mortality predictors in community-acquired pneumonia admitted patients: Importance of comparison with neutrophil count percentage or neutrophil-lymphocyte ratio.

[This corrects the article DOI: 10.1371/journal.pone.0173947.].

Glycosaminoglycans are involved in bacterial adherence to lung cells.

BACKGROUND: Lower respiratory infections are among the top ten causes of death worldwide. Since pathogen to cell adhesion is a crucial step in the infection progress, blocking the interaction between eukaryotic receptors and bacterial ligands may enable the pathogenesis process to be stopped. Cell surface glycosaminoglycans (GAGs) are known to be mediators in the adhesion of diverse bacteria to different cell types, making it of interest to examine their involvement in the attachment of various pathogenic bacteria to lung cells, including epithelial cells and fibroblasts. METHODS: The function of cell surface GAGs in bacterial adhesion was studied by reducing their levels through inhibiting their biosynthesis and enzymatic degradation, as well as in binding competition experiments with various species of GAGs. The participation of the different bacterial adhesins in attachment was evaluated through competition with two peptides, both containing consensus heparin binding sequences. Blocking inhibition assays using anti-syndecans and the enzymatic removal of glypicans were conducted to test their involvement in bacterial adhesion. The importance of the fine structure of GAGs in the interaction with pathogens was investigated in competition experiments with specifically desulfated heparins. RESULTS: The binding of all bacteria tested decreased when GAG levels in cell surface of both lung cells were diminished. Competition experiments with different types of GAGs showed that heparan sulfate chains are the main species involved. Blocking or removal of cell surface proteoglycans evidenced that syndecans play a more important role than glypicans. The binding was partially inhibited by peptides including heparin binding sequences. Desulfated heparins also reduced bacterial adhesion to different extents depending on the bacterium and the sulfated residue, especially in fibroblast cells. CONCLUSIONS: Taken together, these data demonstrate that the GAG chains of the cell surface are involved in the adhesion of bacterial adhesins to lung cells. Heparan sulfate seems to be the main species implicated, and binding is dependent on the sulfation pattern of the molecule. These data could facilitate the development of new anti-infective strategies, enabling the development of new procedures for blocking the interaction between pathogens and lung cells more effectively.

Clinical impact of chronic obstructive pulmonary disease on non-cystic fibrosis bronchiectasis. A study on 1,790 patients from the Spanish Bronchiectasis Historical Registry.

BACKGROUND: Few studies have evaluated the coexistence of bronchiectasis (BE) and chronic obstructive pulmonary disease (COPD) in series of patients diagnosed primarily with BE. The aim of this study was to analyse the characteristics of patients with BE associated with COPD included in the Spanish Bronchiectasis Historical Registry and compare them to the remaining patients with non-cystic fibrosis BE. METHODS: We conducted a multicentre observational study of historical cohorts, analysing the characteristics of 1,790 patients who had been included in the registry between 2002 and 2011. Of these, 158 (8.8%) were registered as BE related to COPD and were compared to the remaining patients with BE of other aetiologies. RESULTS: Patients with COPD were mostly male, older, had a poorer respiratory function and more frequent exacerbations. There were no differences in the proportion of patients with chronic bronchial colonisation or in the isolated microorganisms. A significantly larger proportion of patients with COPD received treatment with bronchodilators, inhaled steroids and intravenous antibiotics, but there was no difference in the use of long term oral or inhaled antibiotherapy. During a follow-up period of 3.36 years, the overall proportion of deaths was 13.8%. When compared to the remaining aetiologies, patients with BE associated with COPD presented the highest mortality rate. The multivariate analysis showed that the diagnosis of COPD in a patient with BE as a primary diagnosis increased the risk of death by 1.77. CONCLUSION: Patients with BE related to COPD have the same microbiological characteristics as patients with BE due to other aetiologies. They receive treatment with long term oral and inhaled antibiotics aimed at controlling chronic bronchial colonisation, even though the current COPD treatment guidelines do not envisage this type of therapy. These patients' mortality is notably higher than that of remaining patients with non-cystic fibrosis BE.

Sex bias in diagnostic delay in bronchiectasis: An analysis of the Spanish Historical Registry of Bronchiectasis.

Diagnostic delay is common in most respiratory diseases, particularly in bronchiectasis. However, sex bias in diagnostic delay has not been studied to date. OBJECTIVE: Assessment of diagnostic delay in bronchiectasis by sex. METHODS: The Spanish Historical Registry of Bronchiectasis recruited adults diagnosed with bronchiectasis from 2002 to 2011 in 36 centres in Spain. From a total of 2113 patients registered we studied 2099, of whom 1125 (53.6%) were women. RESULTS: No differences were found for sex or age (61.0 ± 20.6, p = 0.88) or for localization of bronchiectasis ( p = 0.31). Bronchiectasis of unknown aetiology and secondary to asthma, childhood infections and tuberculosis was more common in women (all ps < 0.05). More men than women were chronic obstructive pulmonary disease-related bronchiectasis and colonized by Haemophilus influenzae ( p < 0.001 for both). Onset of symptoms was earlier in women. The diagnostic delay for women with bronchiectasis was 2.1 years more than for men ( p = 0.001). DISCUSSION: We recorded a substantial delay in the diagnosis of bronchiectasis. This delay was significantly longer in women than in men (>2 years). Independent factors associated with this sex bias were age at onset of symptoms, smoking history, daily expectoration and reduced lung function.

Inflammation biomarkers in blood as mortality predictors in community-acquired pneumonia admitted patients: Importance of comparison with neutrophil count percentage or neutrophil-lymphocyte ratio.

INTRODUCTION: The increase and persistence of inflammation in community-acquired pneumonia (CAP) patients can lead to higher mortality. Biomarkers capable of measuring this inadequate inflammatory response are likely candidates to be related with a bad outcome. We investigated the association between concentrations of several inflammatory markers and mortality of CAP patients. MATERIAL AND METHODS: This was a prospective study of hospitalised CAP patients in a Spanish university hospital. Blood tests upon admittance and in the early-stage evolution (72-120 hours) were carried out, where C-reactive protein, procalcitonin, proadrenomedullin, copeptin, white blood cell, Lymphocyte Count Percentage (LCP), Neutrophil Count Percentage (NCP) and Neutrophil/Lymphocyte Ratio (NLR) were measured. The outcome variable was mortality at 30 and 90 days. Statistical analysis included logistic regression, ROC analysis and area-under-curve test. RESULTS: 154 hospitalised CAP patients were included. Patients who died during follow-up had higher levels of procalcitonin, copeptin, proadrenomedullin, lower levels of LCP, and higher of NCP and NLR. Remarkably, multivariate analysis showed a relationship between NCP and mortality, regardless of age, severity of CAP and comorbidities. AUC analysis showed that NLR and NCP at admittance and during early-stage evolution achieved a good diagnostic power. ROC test for NCP and NLR were similar to those of the novel serum biomarkers analysed. CONCLUSIONS: NLR and NCP, are promising candidate predictors of mortality for hospitalised CAP patients, and both are cheaper, easier to perform, and at least as reliable as the new serum biomarkers. Future implementation of new biomarkers would require comparison not only with classic inflammatory parameters like White Blood Cell count but also with NLR and NCP.

Etiology of Bronchiectasis in a Cohort of 2047 Patients. An Analysis of the Spanish Historical Bronchiectasis Registry. / Etiología de las bronquiectasias en una cohorte de 2.047 pacientes. Análisis del registro histórico español.

INTRODUCTION: Bronchiectasis is caused by many diseases. Establishing its etiology is important for clinical and prognostic reasons. The aim of this study was to evaluate the etiology of bronchiectasis in a large patient sample and its possible relationship with demographic, clinical or severity factors, and to analyze differences between idiopathic disease, post-infectious disease, and disease caused by other factors. METHODS: Multicenter, cross-sectional study of the SEPAR Spanish Historical Registry (RHEBQ-SEPAR). Adult patients with bronchiectasis followed by pulmonologists were included prospectively. Etiological studies were based on guidelines and standardized diagnostic tests included in the register, which were later included in the SEPAR guidelines on bronchiectasis. RESULTS: A total of 2,047 patients from 36 Spanish hospitals were analyzed. Mean age was 64.9years and 54.9% were women. Etiology was identified in 75.8% of cases (post-Infection: 30%; cystic fibrosis: 12.5%; immunodeficiencies: 9.4%; COPD: 7.8%; asthma: 5.4%; ciliary dyskinesia: 2.9%, and systemic diseases: 1.4%). The different etiologies presented different demographic, clinical, and microbiological factors. Post-infectious bronchiectasis and bronchiectasis caused by COPD and asthma were associated with an increased risk of poorer lung function. Patients with post-infectious bronchiectasis were older and were diagnosed later. Idiopathic bronchiectasis was more common in female non-smokers and was associated with better lung function, a higher body mass index, and a lower rate of Pseudomonas aeruginosa than bronchiectasis of known etiology. CONCLUSIONS: The etiology of bronchiectasis was identified in a large proportion of patients included in the RHEBQ-SEPAR registry. Different phenotypes associated with different causes could be identified.

Predictors of Severe Sepsis among Patients Hospitalized for Community-Acquired Pneumonia.

BACKGROUND: Severe sepsis, may be present on hospital arrival in approximately one-third of patients with community-acquired pneumonia (CAP). OBJECTIVE: To determine the host characteristics and micro-organisms associated with severe sepsis in patients hospitalized with CAP. RESULTS: We performed a prospective multicenter cohort study in 13 Spanish hospital, on 4070 hospitalized CAP patients, 1529 of whom (37.6%) presented with severe sepsis. Severe sepsis CAP was independently associated with older age (>65 years), alcohol abuse (OR, 1.31; 95% CI, 1.07-1.61), chronic obstructive pulmonary disease (COPD) (OR, 1.75; 95% CI, 1.50-2.04) and renal disease (OR, 1.57; 95% CI, 1.21-2.03), whereas prior antibiotic treatment was a protective factor (OR, 0.62; 95% CI, 0.52-0.73). Bacteremia (OR, 1.37; 95% CI, 1.05-1.79), S pneumoniae (OR, 1.59; 95% CI, 1.31-1.95) and mixed microbial etiology (OR, 1.65; 95% CI, 1.10-2.49) were associated with severe sepsis CAP. CONCLUSIONS: CAP patients with COPD, renal disease and alcohol abuse, as well as those with CAP due to S pneumonia or mixed micro-organisms are more likely to present to the hospital with severe sepsis.

Sensitivity, Specificity, and Positivity Predictors of the Pneumococcal Urinary Antigen Test in Community-Acquired Pneumonia.

RATIONALE: Detection of the C-polysaccharide of Streptococcus pneumoniae in urine by an immune-chromatographic test is increasingly used to evaluate patients with community-acquired pneumonia. OBJECTIVES: We assessed the sensitivity and specificity of this test in the largest series of cases to date and used logistic regression models to determine predictors of positivity in patients hospitalized with community-acquired pneumonia. METHODS: We performed a multicenter, prospective, observational study of 4,374 patients hospitalized with community-acquired pneumonia. MEASUREMENTS AND MAIN RESULTS: The urinary antigen test was done in 3,874 cases. Pneumococcal infection was diagnosed in 916 cases (21%); 653 (71%) of these cases were diagnosed exclusively by the urinary antigen test. Sensitivity and specificity were 60 and 99.7%, respectively. Predictors of urinary antigen positivity were female sex; heart rate≥125 bpm, systolic blood pressure<90 mm Hg, and SaO2<90%; absence of antibiotic treatment; pleuritic chest pain; chills; pleural effusion; and blood urea nitrogen≥30 mg/dl. With at least six of all these predictors present, the probability of positivity was 52%. With only one factor present, the probability was only 12%. CONCLUSIONS: The urinary antigen test is a method with good sensitivity and excellent specificity in diagnosing pneumococcal pneumonia, and its use greatly increased the recognition of community-acquired pneumonia due to S. pneumoniae. With a specificity of 99.7%, this test could be used to direct simplified antibiotic therapy, thereby avoiding excess costs and risk for bacterial resistance that result from broad-spectrum antibiotics. We also identified predictors of positivity that could increase suspicion for pneumococcal infection or avoid the unnecessary use of this test.

Review of Non-Bacterial Infections in Respiratory Medicine: Viral Pneumonia.

Although bacteria are the main pathogens involved in community-acquired pneumonia, a significant number of community-acquired pneumonia are caused by viruses, either directly or as part of a co-infection. The clinical picture of these different pneumonias can be very similar, but viral infection is more common in the pediatric and geriatric populations, leukocytes are not generally elevated, fever is variable, and upper respiratory tract symptoms often occur; procalcitonin levels are not generally affected. For years, the diagnosis of viral pneumonia was based on cell culture and antigen detection, but since the introduction of polymerase chain reaction techniques in the clinical setting, identification of these pathogens has increased and new microorganisms such as human bocavirus have been discovered. In general, influenza virus type A and syncytial respiratory virus are still the main pathogens involved in this entity. However, in recent years, outbreaks of deadly coronavirus and zoonotic influenza virus have demonstrated the need for constant alert in the face of new emerging pathogens. Neuraminidase inhibitors for viral pneumonia have been shown to reduce transmission in cases of exposure and to improve the clinical progress of patients in intensive care; their use in common infections is not recommended. Ribavirin has been used in children with syncytial respiratory virus, and in immunosuppressed subjects. Apart from these drugs, no antiviral has been shown to be effective. Prevention with anti-influenza virus vaccination and with monoclonal antibodies, in the case of syncytial respiratory virus, may reduce the incidence of pneumonia.

The incidence of cardiovascular events after hospitalization due to CAP and their association with different inflammatory markers.

BACKGROUND: Late prognosis of Community-Acquired Pneumonia (CAP) patients is related to cardiovascular events. Persistence of inflammation-related markers, defined by high circulatory levels of interleukin 6 and 10 (IL-6/IL-10), is associated with a higher post-event mortality rate for CAP patients. However, association between these markers and other components of the immune response, and the risk of cardiovascular events, has not been adequately explored. The main objectives of this study are: 1) to quantify the incidence of cardiovascular disease, in the year post-dating their hospital admittance due to CAP and, 2) to describe the distribution patterns of a wide spectrum of inflammatory markers upon admittance to and release from hospital, and to determine their relationship with the incidence of cardiovascular disease. METHODS/DESIGN: A cohort prospective study. All patients diagnosed and hospitalized with CAP will be candidates for inclusion. The study will take place in the Universitary Hospital La Princesa, Spain, during two years. Two samples of blood will be taken from each patient: the first upon admittance and the second one prior to release, in order to analyse various immune agents. The main determinants are: pro-adrenomedullin, copeptin, IL-1, IL-6, TNF-α, IL-17, IFN-γ, IL-10 and TGF-ß, E-Selectin, ICAM-1, VCAM-1 and subpopulations of peripheral T lymphocytes (T regulator, Th1 and Th17), together with other clinical and analytical variables. Follow up will start at admittance and finish a year after discharge, registering incidence of death and cardiovascular events. The main objective is to establish the predictive power of different inflammatory markers in the prognosis of CAP, in the short and long term, and their relationship with cardiovascular disease. DISCUSSION: The level of some inflammatory markers (IL-6/IL-10) has been proposed as a means to differentiate the degree of severity of CAP, but their association with cardiovascular risk is not well established. In this study we aim to define new inflammatory markers associated with cardiovascular disease that could be helpful for the prognosis of CAP patients, by describing the distribution of a wide spectrum of inflammatory mediators and analyzing their association with the incidence of cardiovascular disease and mortality one year after release from hospital.

Surfactant protein A genetic variants associate with severe respiratory insufficiency in pandemic influenza A virus infection.

INTRODUCTION: Inherited variability in host immune responses influences susceptibility and outcome of Influenza A virus (IAV) infection, but these factors remain largely unknown. Components of the innate immune response may be crucial in the first days of the infection. The collectins surfactant protein (SP)-A1, -A2, and -D and mannose-binding lectin (MBL) neutralize IAV infectivity, although only SP-A2 can establish an efficient neutralization of poorly glycosylated pandemic IAV strains. METHODS: We studied the role of polymorphic variants at the genes of MBL (MBL2), SP-A1 (SFTPA1), SP-A2 (SFTPA2), and SP-D (SFTPD) in 93 patients with H1N1 pandemic 2009 (H1N1pdm) infection. RESULTS: Multivariate analysis showed that two frequent SFTPA2 missense alleles (rs1965708-C and rs1059046-A) and the SFTPA2 haplotype 1A(0) were associated with a need for mechanical ventilation, acute respiratory failure, and acute respiratory distress syndrome. The SFTPA2 haplotype 1A(1) was a protective variant. Kaplan-Meier analysis and Cox regression also showed that diplotypes not containing the 1A(1) haplotype were associated with a significantly shorter time to ICU admission in hospitalized patients. In addition, rs1965708-C (P = 0.0007), rs1059046-A (P = 0.0007), and haplotype 1A(0) (P = 0.0004) were associated, in a dose-dependent fashion, with lower PaO2/FiO2 ratio, whereas haplotype 1A(1) was associated with a higher PaO2/FiO2 ratio (P = 0.001). CONCLUSIONS: Our data suggest an effect of genetic variants of SFTPA2 on the severity of H1N1pdm infection and could pave the way for a potential treatment with haplotype-specific (1A(1)) SP-A2 for future IAV pandemics.

The role of mannose-binding lectin in pneumococcal infection.

The role of mannose-binding lectin (MBL) deficiency (MBL2; XA/O and O/O genotypes) in host defences remains controversial. The surfactant proteins (SP)-A1, -A2 and -D, other collectins whose genes are located near MBL2, are part of the first-line lung defence against infection. We analysed the role of MBL on susceptibility to pneumococcal infection and the existence of linkage disequilibrium (LD) among the four genes. We studied 348 patients with pneumococcal community-acquired pneumonia (P-CAP) and 2,110 controls. A meta-analysis of MBL2 genotypes in susceptibility to P-CAP and to invasive pneumococcal disease (IPD) was also performed. The extent of LD of MBL2 with SFTPA1, SFTPA2 and SFTPD was analysed. MBL2 genotypes did not associate with either P-CAP or bacteraemic P-CAP in the case-control study. The MBL-deficient O/O genotype was significantly associated with higher risk of IPD in a meta-analysis, whereas the other MBL-deficient genotype (XA/O) showed a trend towards a protective role. We showed the existence of LD between MBL2 and SP genes. The data do not support a role of MBL deficiency on susceptibility to P-CAP or to IPD. LD among MBL2 and SP genes must be considered in studies on the role of MBL in infectious diseases.