Development and evaluation of a multiplex test for the detection of atypical bacterial DNA in community-acquired pneumonia during childhood

AbstractAn incorrect or late diagnosis can lead to an increase in the morbidity and mortality caused by pneumonia, and the availability of a rapid and accurate microbiological test to verify the aetiology is imperative. This study evaluated a molecular test for the identification of the bacterial cause of atypical community-acquired pneumonia (ACAP). Fifty-four children with pneumonia were studied using bacteriological cultures, Mycoplasma pneumoniae, Coxiella burnetii, Chlamydophila pneumoniae and Legionella spp. serology, and Streptococcus pneumoniae and Legionella antigens. Simultaneously, the presence of bacterial and fungal DNA was tested for in respiratory secretion samples using the Vircell SL kit, including multiplex PCR and amplicon detection by means of line blots. There were 14 cases of ACAP caused by M. pneumoniae, with positive kit results for 13 of them, and two cases of Q-fever, with negative kit results for Coxiella burnetii. The test was negative in the remaining 38 cases (one staphylococcal pneumonia, 20 Streptococcus pneumoniae pneumonias, and 17 probable viral pneumonias). The sensitivity of the test for the detection of M. pneumoniae was 92.8% and the specificity was 100%. The Vircell SL kit allows detection of M. pneumoniae DNA in respiratory secretion samples from children with ACAP

Evaluation of a rapid test for the identification of Mycobacterium tuberculosis and six other species of atypical mycobacteria directly from sputum

Introducción: El diagnóstico de tuberculosis y, en general, de la patología infecciosa causada por micobacterias, es un proceso lento, que retrasa considerablemente el inicio de un tratamiento antibiótico adecuado. El desarrollo de técnicas moleculares que permitan la detección e identificación de micobacterias directamente en la muestra clínica sería un procedimiento deseable para acortar este periodo. Material y métodos: Se usaron siete cepas de referencia internacional de micobacterias para inocular, de forma artificial, esputos, y realizar pruebas que determinasen la capacidad del ensayo Speed-Oligo Micobacteria® para identificar dichas bacterias directamente, sin necesidad de sembrar las muestras en los medios de cultivo convencionales. Resultados: El ensayo identificó correctamente las siete cepas utilizadas, incluso cuando las bacterias se encontraron en concentraciones inferiores a los límites de detección de la baciloscopia. Conclusiones: El ensayo Speed-Oligo Mycobacteria® podría ser válido para la detección e identificación directa de micobacterias en esputos, incluso en aquellos que presentan una baciloscopia negativa.Introduction: The diagnosis of tuberculosis and, in general, infectious disease caused by mycobacteria is a slow process, which significantly delayed the initiation of appropriate antibiotic therapy. The development of molecular techniques that allow detection and identification of mycobacteria directly from clinical specimen would be a desirable to shorten this period. Material and methods: We used seven international reference strains of mycobacteria to inoculate, artificially, sputum, and perform tests that determine the ability of the Oligo Speed Mycobacteria® to identify the bacteria directly, without having to grow the samples in conventional culture media. Results: The test correctly identified seven strains used, even when the bacteria were found at concentrations below the detection limits of the smear. Conclusions: The Speed-Oligo Mycobacteria® could be valid for the direct detection and identification of mycobacteria in sputum, including those with a negative smea

Characterization of daptomycin non-susceptible enterococcus faecium producing urinary tract infection in a renal transplant recipient

Objetivos. Presentamos la caracterización de un aislado de Enterococcus faecium no sensible a daptomicina, recuperado de una muestra de orina de un paciente con trasplante de riñón e infección urinaria y sin antecedentes de exposición previa a daptomicina. Métodos. Tras el aislamiento, la identificación de E. faecium fue confirmada por la amplificación del gen que codifica la región específica de la ligasa de la D-alanil-D-alanina (ddl) y la prueba de sensibilidad a daptomicina se realizó mediante E-test en agar Mueller-Hinton ajustado para cationes. Con el fin de determinar las bases genéticas de la resistencia a daptomicina, se secuenciaron las regiones de lectura abierta de cinco genes previamente asociados con la resistencia a daptomicina en enterococos. Resultados. Se identificaron cambios en el promotor de LiaR (S19F) y la sintetasa de la cardiolipina (R218Q). Conclusiones. Esta es la primera caracterización de un aislado clínico de E. faecium con resistencia a daptomicina en un hospital español, en ausencia de exposición previa y en un receptor de trasplante renal.Objectives. Characterization of a urine isolate of daptomycin non-susceptible Enterococcus faecium recovered from a patient with kidney transplantation and no history of daptomycin exposure. Methods. After isolation in a urine sample, identification of E. faecium was confirmed by amplification of the E. faecium-specific gene encoding D-alanyl-D-alanine ligase (ddl) and daptomycin susceptibility testing was performed by E-test on cation-adjusted Mueller-Hinton agar. In order to determine the genetic bases of daptomycin resistance, the open reading frames of five genes previously associated with daptomycin resistance in enterococci were sequenced. Results. Substitutions in the response regulator LiaR (S19F) and cardiolipin synthase (R218Q) were identified. Conclusions. To the best of our knowledge, this is the first characterization of emerging daptomycin resistance in E. faecium in a Spanish hospital in the absence of daptomycin exposure and in a renal transplant recipien

Características sociodemográficas y factores de riesgo asociados a las bacteriurias significativas en un área de salud del sudeste español.

To determine the epidemiological characteristics of significative bacteriuria (SB) and their relationship with sociodemographic factors and to analyze risk factors in inpatients. Cross-sectional descriptive study carried out on urine culture samples received between 2016-2020 in the Microbiology laboratory, differentiating between minors and adults. The dependent variable was the presence of SB and the independent variables were age, sex, year, type of sample and source of the sample. In urine cultures of inpatients, risk factors were evaluated from the Minimum Basic Data Set. A total of 68,587 valid records (96.3% of the total) were analyzed. 40.8% (95% CI: 40.4%-41.2%) of urine cultures in adults and 33.8% (95% CI: 32.9%-34.7%) in children were positive, with an incidence that ranged in adults between 18.2 cases/1,000 inhabitants in 2016 and 14.6 cases/1,000 inhabitants in 2020 and 21.1 and 8.4 cases/1,000 inhabitants respectively in minors. Positive urine cultures were more frequent in children from urban areas compared to rural areas (OR=1.37; p The sociodemographic characteristics of the population with SB in our health area are similar to those found in other geographical areas worldwide, observing a decreasing trend in incidence in the years studied. The frequency of SB in children is higher in urban areas

Different presence of Chlamydia pneumoniae, herpes simplex virus type 1, human herpes virus 6, and Toxoplasma gondii in schizophrenia: meta-analysis and analytical study

José Gutiérrez-Fernández,1 Juan de Dios Luna del Castillo,2 Sara Mañanes-González,1 José Antonio Carrillo-Ávila,1 Blanca Gutiérrez,3 Jorge A Cervilla,3 Antonio Sorlózano-Puerto1 1Department of Microbiology, 2Department of Statistics and Operation Research, 3Department of Psychiatry, Institute of Neurosciences and CIBERSAM, School of Medicine and Biohealth Research Institute (Instituto de Investigación Biosanitaria) IBS-Granada, University of Granada, Granada, Spain Abstract: In the present study we have performed both a meta-analysis and an analytical study exploring the presence of Chlamydia pneumoniae, herpes simplex virus type 1, human herpes virus 6, and Toxoplasma gondii antibodies in a sample of 143 schizophrenic patients and 143 control subjects. The meta-analysis was performed on papers published up to April 2014. The presence of serum immunoglobulin G and immunoglobulin A was performed by enzyme-linked immunosorbent assay test. The detection of microbial DNA in total peripheral blood was performed by nested polymerase chain reaction. The meta-analysis showed that: 1) C. pneumoniae DNA in blood and brain are more common in schizophrenic patients; 2) there is association with parasitism by T. gondii, despite the existence of publication bias; and 3) herpes viruses were not more common in schizophrenic patients. In our sample only anti-Toxoplasma immunoglobulin G was more prevalent and may be a risk factor related to schizophrenia, with potential value for prevention. Keywords: meta-analysis, analytical study, Chlamydia pneumoniae, herpes simplex virus type 1, human herpes virus 6, Toxoplasma gondii, schizophreni

Toxoplasma gondii Seropositivity Interacts with Catechol-O-methyltransferase Val105/158Met Variation Increasing the Risk of Schizophrenia

Schizophrenia is a heterogeneous and severe psychotic disorder. Epidemiological findings have suggested that the exposure to infectious agents such as Toxoplasma gondii (T. gondii) is associated with an increased risk for schizophrenia. On the other hand, there is evidence involving the catechol-O-methyltransferase (COMT) Val105/158Met polymorphism in the aetiology of schizophrenia since it alters the dopamine metabolism. A case–control study of 141 patients and 142 controls was conducted to analyse the polymorphism, the prevalence of anti-T. gondii IgG, and their interaction on the risk for schizophrenia. IgG were detected by ELISA, and genotyping was performed with TaqMan Real-Time PCR. Although no association was found between any COMT genotype and schizophrenia, we found a significant association between T. gondii seropositivity and the disorder (χ2 = 11.71; p-value < 0.001). Furthermore, the risk for schizophrenia conferred by T. gondii was modified by the COMT genotype, with those who had been exposed to the infection showing a different risk compared to that of nonexposed ones depending on the COMT genotype (χ2 for the interaction = 7.28, p-value = 0.007). This study provides evidence that the COMT genotype modifies the risk for schizophrenia conferred by T. gondii infection, with it being higher in those individuals with the Met/Met phenotype, intermediate in heterozygous, and lower in those with the Val/Val phenotype