Aetiology of community acquired pneumonia in Valencia, Spain: a multicentre prospective study.

A year long multicentre prospective study was carried out in the Valencia region of Spain, to determine the cause of community acquired pneumonia. The study was based on 510 of 833 patients with pneumonia. Of these, 462 were admitted to hospital, where 31 patients died. A cause was established in only 281 cases--208 of bacterial, 60 of viral, and 13 of mixed infection. The most common microorganisms were Streptococcus pneumoniae (14.5%), Legionella sp (14%), Influenza virus (8%), and Mycoplasma pneumoniae (4%). There was a higher incidence of Legionella sp than in other studies.

Karyotypic diversity among Blastocystis hominis isolates

Fifteen Blastocystis hominis strains, 13 axenic and 2 monoxenic, have been included in the present study. The chromosomal pattern was analyzed by the contour-clamped homogeneous electric-field (CHEF) system. The number of chromosomes detected ranged between 9 and 13, with sizes from 2200 kbp to 260 kbp. Eleven karyotypic profiles, with a common pattern constituted by 8 chromosomes of 2200, 1280, 890, 840, 700, 650, 540 and 260 kbp, were observed. The Jaccard index demonstrated that the similarity between isolates ranged from 0.5714 to 1. The different isolates were clustered in 3 karyotypes (A: 8 isolates; B: 6 isolates and C: 1 isolate). All isolates grouped in karyotype A presented a char…

Chagas Disease Vector Control in a Hyperendemic Setting: The First 11 Years of Intervention in Cochabamba, Bolivia

Background Chagas disease has historically been hyperendemic in the Bolivian Department of Cochabamba. In the early 2000s, an extensive vector control program was implemented; 1.34 million dwelling inspections were conducted to ascertain infestation (2000–2001/2003–2011), with blanket insecticide spraying in 2003–2005 and subsequent survey-spraying cycles targeting residual infestation foci. Here, we assess the effects of this program on dwelling infestation rates (DIRs). Methodology/Principal Findings Program records were used to calculate annual, municipality-level aggregate DIRs (39 municipalities); very high values in 2000–2001 (median: 0.77–0.69) dropped to ∼0.03 from 2004 on. A linear…

Performance characteristics of the new Abbott Real Time MTB assay for detection of Mycobacterium tuberculosis complex in respiratory specimens

The performance of the Abbott Real Time MTB assay for detection of Mycobacterium tuberculosis complex in respiratory specimens was evaluated using a standard culture as the reference. The overall concordance between both methods was 0.95. The assay displayed an excellent sensitivity (100% for smear-positive/92.3% for smear-negative specimens) and specificity (100%).

In vitro activity of linezolid, clarithromycin and moxifloxacin against clinical isolates of Mycobacterium kansasii

To compare the activity of linezolid with a range of drugs used in the treatment of Mycobacterium kansasii infections.The percentages of resistant isolates against isoniazid, rifampicin and ethambutol were 2.9%, 1.9% and 2.9%, respectively. All isolates were susceptible to clarithromycin and moxifloxacin both with MIC(90) values of 0.125 mg/L. Linezolid was active against all isolates with MIC(50) and MIC(90) values of 0.5 and 1 mg/L, respectively, both below the susceptibility breakpoint established for mycobacteria.Linezolid, clarithromycin or moxifloxacin, could be used as alternative drugs for treatment of infections due to rifampicin-resistant isolates as well as short-course or interm…

New agents active against Mycobacterium avium complex selected by molecular topology: a virtual screening method

Objectives: In order to select new drugs and to predict their in vitro activity against Mycobacterium avium complex (MAC), new quantitative structure-activity relationship (QSAR) models were developed. Methods: The activities against MAC of 29 structurally heterogeneous drugs were examined by means of linear discriminant analysis (LDA) and multilinear regression analysis (MLRA) by using topological indices (TI) as structural descriptors. In vitro antimycobacterial activities were determined by a broth microdilution method with 7H9 medium. Results: The topological model obtained successfully classifies over 80% of compounds as active or inactive; consequently, it was applied in the search fo…

Search of Chemical Scaffolds for Novel Antituberculosis Agents

3 A method to identify chemical scaffolds potentially active against Mycobacterium tuberculosis is presented. The molecular features of a set of structurally heterogeneous antituberculosis drugs were coded by means of structural invariants. Three tech- niques were used to obtain equations able to model the antituberculosis activity: linear discriminant analysis, multilinear re- gression, and shrinkage estimation-ridge regression. The model obtained was statistically validated through leave-n-out test, and an external set and was applied to a database for the search of new active agents. The selected compounds were assayed in vitro, and among those identified as active stand reserpine, N,N,N…

Soluble-protein and antigenic heterogeneity in axenic Blastocystis hominis isolates: pathogenic implications.

The protein profile and the antigenic cross-reactivity of 18 axenic isolates of Blastocystis hominis obtained from symptomatic patients with chronic diarrhea (14 isolates) showing no evidence of parasitic etiology and from patients with acute diarrhea attributable in 2 cases to Salmonella spp. were analyzed. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of soluble proteins showed the existence of a common profile composed of 31 bands, with molecular weights ranging between 24 and >200 kDa, and minor differences in the proteins of 149, 118, 106, 50, 48, 47, and 30 kDa. These differences allowed us to classify the strains into three related patterns (I–III). In an indirect immunof…

Clinical significance of Pneumocystis jirovecii DNA detection by real-time PCR in hematological patient respiratory specimens

Description of an improved method for Blastocystis hominis culture and axenization

An improved method for Blastocystis hominis culture and axenization was developed in the present study. Stool samples were cultured in prereduced Boeck-Drbohlav NHI modified medium (with several modifications) supplemented with antibiotics (0.4% ampicillin, 0.1% streptomycin, 0.0006% amphotericin B). Axenization was performed by the combination of partial purification of B. hominis by Ficoll-metrizoic acid gradient and inoculation in fresh medium containing active antibiotics against remaining bacteria. A total of 25 strains were obtained by this procedure. The time required for axenization ranged between 3 and 5 weeks. The generation time of axenic strains ranged from 6.6 to 12.1 h (mean +…

Towards next-generation diagnostics for tuberculosis: identification of novel molecular targets by large-scale comparative genomics.

5 páginas, 2 figuras. AVAILABILITY AND IMPLEMENTATION: The database of non-tuberculous mycobacteria assemblies can be accessed at: 10.5281/zenodo.3374377. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online: http://dx.doi.org/10.1093/bioinformatics/btz729

Performance of a Highly Sensitive Mycobacterium tuberculosis Complex Real-Time PCR Assay for Diagnosis of Pulmonary Tuberculosis in a Low-Prevalence Setting: a Prospective Intervention Study

ABSTRACT The potential impact of routine real-time PCR testing of respiratory specimens from patients with presumptive tuberculosis in terms of diagnostic accuracy and time to tuberculosis treatment inception in low-prevalence settings remains largely unexplored. We conducted a prospective intervention cohort study. Respiratory specimens from 1,020 patients were examined by acid-fast bacillus smear microscopy, tested by a real-time Mycobacterium tuberculosis complex PCR assay (Abbott RealTi me MTB PCR), and cultured in mycobacterial media. Seventeen patients tested positive by PCR (5 were acid-fast bacillus smear positive and 12 acid-fast bacillus smear negative), and Mycobacterium tubercul…

Incidence, risk factors, and outcome of pulmonary invasive fungal disease after respiratory virus infection in allogeneic hematopoietic stem cell transplantation recipients

Abstract Background There is growing evidence that community‐acquired respiratory virus (CARV) increases the risk of pulmonary invasive fungal disease (IFD) in the allogeneic hematopoietic stem cell transplantation (allo‐HSCT) setting. To date, there is a lack of knowledge regarding the risk factors (RFs), as well as the most critical period for subsequent onset of IFD after CARV infections in allo‐HSCT recipients. Methods In this prospective longitudinal observational CARV survey, we analyzed the effect of CARV on subsequent IFD development in 287 adult allo‐HSCT recipients diagnosed with 597 CARV episodes from December 2013 to December 2018. Multiplex PCR panel assays were used to test CA…

Epidemiology of invasive candidiasis in a surgical intensive care unit: an observational study

Background: Invasive candidiasis (IC) is a frequent and life-threatening infection in critically ill patients. The aim of this study was to evaluate the epidemiology of IC and the antifungal susceptibility of etiological agents in patients admitted to our surgical intensive care unit (SICU) in Spain. Methods: We designed a prospective, observational, single center, population-based study in a SICU. We included all consecutive adult patients (≥18 years old) who had documented IC, either on admission or during their stay, between January 2012 and December 2013. Results: There were a total of 22 episodes of IC in the 1149 patients admitted during the 24-month study. The overall IC incidence wa…

Towards next generation diagnostics for tuberculosis: identification of novel molecular targets by large-scale comparative genomics

AbstractTuberculosis remains one of the main causes of death worldwide. The long and cumbersome process of culturingMycobacterium tuberculosiscomplex (MTBC) bacteria has encouraged the development of specific molecular tools for detecting the pathogen. Most of these tools aim to become novel tuberculosis diagnostics, and big efforts and resources are invested in their development, looking for the endorsement of the main public health agencies. Surprisingly, no study had been conducted where the vast amount of genomic data available is used to identify the best MTBC diagnostic markers. In this work, we use large-scale comparative genomics to provide a catalog of 30 characterized loci that ar…

Diagnostics upon Hospital Release of Immigrants in the City of Valencia, Spain (2001-2002)

Fundamento: La inmigracion en Espana se ha incrementado de forma notable en la ultima decada. Por razones teoricas se ha planteado que esta poblacion pudiera ser responsable de un aumento de la incidencia y/o transmision de enfermedades infecciosas. Sin embargo, existen escasos estudios acerca de las enfermedades de este colectivo que permitan conocer la importancia de esta afirmacion. El objetivo de este estudio es cuantificar la atencion hospitalaria a esta poblacion en la ciudad de Valencia. Metodos: Se obtuvieron los registros de altas de los Servicios de Admision de los hospitales publicos de la ciudad de Valencia. Se desarrollo un estudio observacional retrospectivo para el ano compre…

Eosinophil-selective mediators in human strongyloidiasis

SUMMARY Strongyloides stercoralis infection is characterized by the production of IgE and eosinophils in peripheral blood. Experimental studies have demonstrated that eosinophils play an important role in protection against Strongyloides stercoralis, but the mechanisms regulating eosinophils are not known. In this study we have focused on analysing the molecules that selectively regulate eosinophil migration, namely eotaxin and interleukin-5 (IL-5), using an enzyme-linked immunosorbent assay in patients with strongyloidiasis. Serum expression of eotaxin and IL-5 were significantly increased in patients compared with the control group. This rise suggests that selective mediators of the eosin…

Field performance of the Abbott RealTime MTB assay for the diagnosis of extrapulmonary tuberculosis in a low-prevalence setting

Introduction: The sensitivities of conventional mycobacterial culture in solid or liquid media and acid-fast bacilli (AFB) smear microscopy for Mycobacterium tuberculosis complex (MTBC) detection in extrapulmonary specimens are suboptimal. We evaluated the field performance of the Abbott RealTime MTB assay for the diagnosis of extrapulmonary tuberculosis in a low-prevalence setting. Methods: The total number of extrapulmonary specimens with mycobacterial culture and PCR results was 566: sterile fluids (n = 278), non-sterile fluids (n = 147), lymph node material (n = 69) tissue biopsies (n = 63), and abscess aspirates (n = 9). A composite standard consisting of mycobacterial culture results,…

Similarity-Based Virtual Screening to Find Antituberculosis Agents Based on Novel Scaffolds: Design, Syntheses and Pharmacological Assays

A method to identify molecular scaffolds potentially active against the Mycobacterium tuberculosis complex (MTBC) is developed. A set of structurally heterogeneous agents against MTBC was used to obtain a mathematical model based on topological descriptors. This model was statistically validated through a Leave-n-Out test. It successfully discriminated between active or inactive compounds over 86% in database sets. It was also useful to select new potential antituberculosis compounds in external databases. The selection of new substituted pyrimidines, pyrimidones and triazolo[1,5-a]pyrimidines was particularly interesting because these structures could provide new scaffolds in this field. T…

High prevalence of Blastocystis sp. in pigs reared under intensive growing systems: Frequency of ribotypes and associated risk factors

Three hundred and ninety-five pig fecal samples were analyzed looking for Blastocystis sp. using optical microscopy and PCR. A global prevalence of 46.8% has been observed in this study, although relative values of prevalence differ notably according to the strata examined, ranging from 9.3% in sows to 75% in weaners. Statistic analysis of the data included several risk factors such as different management systems, date of sample collection, fecal consistency, age and sex of the animals. The presence of the parasite was statistically associated to the variables "age" and "date of sample collection", being more prevalent in weaners and grower pigs and warm season. Random fragment-length poly…

Occurrence and genotypes of Giardia isolated from lambs in Spain

Three hundred and eighty six faecal specimens were randomly collected from 1- to 3-month-old lambs from 16 farms in Spain to investigate the presence of different genotypes of Giardia duodenalis. Individual specimens were examined by IFA (Immunofluorescence assay) and beta-giardin PCR polymerase chain reaction. Cysts of G. duodenalis were shed by lambs in every flock analyzed, showing a prevalence by farms of 100%. The average prevalence of G. duodenalis for the 386 specimens was 42%, ranging from 8.3 to 80% depending on the farm. beta-giardin PCR positive samples were sequenced to determine the genotypes present at each farm and seven new subtypes of beta-giardin Assemblage E are reported …

Frequent detection of cytomegalovirus (CMV) DNA in the lower respiratory tract in CMV-seropositive pediatric patients with underlying chronic bronchopulmonary diseases lacking canonical immunosuppression

Abstract Cytomegalovirus (CMV) may be a relevant cause of morbidity in patients displaying various inflammatory diseases. In this study, it was investigated whether CMV DNA is detected in the lower respiratory tract and the systemic compartment in pediatric patients with chronic or recurrent bronchopulmonary diseases. A total of 42 lower respiratory tract specimens and 11 paired plasma samples from 42 patients were analyzed for the presence of CMV DNA by real‐time PCR. The respiratory specimens were also screened for the presence of respiratory viruses and human herpesvirus 6 (HHV‐6) and 7 (HHV‐7) by PCR methods. Quantitative bacterial and fungal cultures were performed. IL‐6 levels in the …

Diagnostic accuracy and potential clinical value of the LightCycler SeptiFast assay in the management of bloodstream infections occurring in neutropenic and critically ill patients

Summary Objectives The objectives of this study were to compare the performance of the LightCycler SeptiFast Test MGRADE and conventional blood culture in the etiological diagnosis of febrile episodes occurring in neutropenic and critically ill patients (in the intensive care unit; ICU), and to assess the potential clinical value of the SeptiFast test in patient management. Methods A total of 86 febrile episodes occurring in 33 neutropenic patients and 53 ICU patients were analyzed. Blood samples for blood culture and SeptiFast testing were obtained at the onset of fever, before the implementation of empirical antimicrobial therapy. Results The overall microorganism-to-isolate agreement bet…

Whole-genome sequencing of Mycobacterium tuberculosis directly from clinical samples for high-resolution genomic epidemiology and drug resistance surveillance: an observational study

9 páginas, 3 figuras